'91TealRS

Hi,
I have been working on this a LONG time. When the car first starts off, there is a noticeable lag sometimes severe enough to stall. The injectors that were in it were running REAL rich, but even then, if you stomped on it, it would stall. I ran it until the cat plugged up, forcing hot exhaust out the $200 electronic EGR valve, and taking out the ignition module(due to heat).

Got the injectors out, some were reading less than 8 ohms (very bad), replaced them, cut out the cat, replaced the entire contents of the distributor, new EGR, wires, plugs, coil. The car ran 200% better, but now the hesitation was much worse.

Started replacing every sensor and control known to man: MAP, IAC, TPS, O2 (tried 2 of those, the AC Delco with purple wire), temperture sensor, A.I.R management valve (another $200 item), A.I.R Check Valve. Disconnected and plugged the hose from the vapor cannister (no difference). Checked the fuel pressure, it's within specs ( 47psi no vacuum, 37psi full vacuum).

We here in CA. have "Test Only" smog checks, where your car is randomly selected, and, last Aug., mine was. So, I pulled the exhaust manifolds off, as they had many leaks, found a broken bolt (and a missing one), so pulled the heads to extract it. While the heads were off, had them vacuum checked, and surfaced. My mechanic friend knows the shop, and thinks anything with less than 8cyl is a POS, so he told them just to vacuum check them, I thought they would re-face the valves (this may be the cause), at least I had them resurface the mating surface. When trying to re-install the left manifold, the bolt holes didn't line up!! Bought a new manifold, no gaskets are available for cast iron heads, so I got a set for aluminum heads (ain't gonna find no leaks in MY car!).

An interesting note: the two rear cyl. #5 and #6 had white deposits in the exhaust runners, the others were black (maybe too much air from the power brake)

The car passed smog, the HC was a little high, but within limits. The limit for 15MPH (yes we have treadmill smog machines) is 112PPM, with the average car putting out 31 PPM, and mine putting out 75PPM. At 25MPH, the limit is 86, with a 20 average, mine was at 78 (close).

Well, I really want to find out what is going on, so I broke down, and took it to a shop with a machine. They checked everything, and it showed OK. BUT... in the Snap-On guide it shows the PROM being updated for... hesitation. They ordered one from a dealer in So CA., as GM has discontinued them. Thjey put it in, and now the shift light stays on in 5th. They put in one for an automatic, and that is the converter lockup signal. Did some research on my own, got the right one, installed it, still hesitates.
It also has that awful "lean misfire" smell, the shop said the exhaust system was leaking everywhere (bad welds at the cat and muffler).

My Berretta 2.8 which was my everyday driver, lost the timing chain, prompting me to change the chain on the Camaro, glad I did, the tensioner was brittle, and ready to go. That helped the smell, but it is still there. Got new muffler, and all the leaks fixed, still smells.

I installed an MSD 6A which I had bought 10 years ago for a long-dead car, and put that in, thinking it will burn any unburned gas. Gets better fuel mileage, but STILL SMELLS, STILL HESITATES.

Another note, the very first acceleration when started is fine (no hesitation), but every subsequent shift, the lag is there. Seems after decel, it is worse. When the computer goes into closed loop, it gets better, but is still there. The new PROM helped the hesitation in open loop (it was VERY bad with the original PROM). I also installed a stage 1 performance chip from JET, with the updated PROM. Still hesitates.

If anyone is still reading, thank you, but I wanted to get ALL the info out, to avoid all the usual questions.

NOW.... has ANYBODY had experience with this? Any suggestions?

Thanks for any help, and for reading this through

Bob

EDIT: the cat is replaced with a high-flow used unit.

kretos

this may sound stupid, but have you replaced the pcv valve? its a 3 dollar part and solved a few similiar issues i had

'91TealRS

Here I thought I covered everything in my 3 page post

Yes, PCV, fuel filter (twice), air filter, all replaced

I tried plugging off the PCV line, made sure there is no vacuum leak, even plugged off the power brake booster (sure is hard to stop), no difference.

About the only thing I haven't replaced is the ECM itself, and a rebuilt really isn't that expensive. Any thoughts on that?

Maybe the valves aren't seating, letting air back into the intake, anyone heard of that affecting throttle response? This is a speed-density system, vacuum leaks shouldn't really have much effect, except to raise idle speed.

Is there a way I can change over to a MAF system?

Thanks again,

Bob

kretos

hmmm, i doubt it would be a problem, have you replaced your air filter?

i know these things sound small, but usually the little things are what are causing a problem, what's the timing set at?

i'm assuming the car isn't throwing any codes, but how old is the cts? i was getting a real bad hesitation when mine went bad and i never got a code off it

'91TealRS

Yes, air filter replaced. Nope, no codes. What is a CTS?

I edited the last post after you sent this.

kretos

coolant temperature sensor

also with the ecm, if it was bad your car wouldn't run, rebuilt units tend to be complete garbage, they basically take old ones give them quick visuals, solder anything that looks bad and send it out, no testing is usually done and they tend not to last.

Yes you could convert over to an maf setup, you might want to contact Doward, he could steer you in the right direction

'91TealRS

Oh, yeah, see my original post, I included that.

'91TealRS

[QUOTE=kretos what's the timing set at?

[/QUOTE]

Sorry, didn't see that item. It's set a little advanced, 14o. The book says 10BTDC, I gave it a little kick. I experimented with that, too. I turned it back to about 0o, it ran hot, slow, poor fuel mileage, but the hesitation was better. I did this before replacing the PROM and timing chain.

Another interesting item: when I changed the timing chain, and aligned the sprockets, the timing mark was NOT at 0o, it was 6o off. I triple checked my findings, wish I had the heads off then to see the piston. But the mark on the crank sprocket was straight up, and the timing mark was 6o ATDC. I got a security torx bit and adjusted it.

Rexer

Hi, iv been having the same problem as you on my 92 firebird 3.1, i get a hesitation when i step on and off the gas, also bucks like a bronco when in gear rolling with traffic. id love to find a cure,
iv changed
plugs
cap
rotor
leads
things i intend to change next are
icm
pickup coil
coil
leads(again)
and im gona chjeck fuel pressure.
if i find a cure before you il let you know.
Nick (uk)

85berlinetta2.8

to the original poster
you do plugs cap and rotor and make sure the tps is set within spec?

'91TealRS

Yes all distributor parts are new except, well, the core. As far as the TPS, there is no "setting", the computer learns the resistance value of closed throttle upon re-connecting the battery. I had an adjustable one I got off an 88 Grand Prix 2.8, which had slots. I did move it without resetting the computer once, and the shift light came on when idling with the vehicle moving. The service manual will tell you that the computer learns the resistance values. The new replacement unit has round mount holes, with no room for adj.

Doward seems to think the injectors may be wrong, and, since I re-surfaced the heads, the intake may not be lined up right (vacuum leak), but the condition was there before the re-surface

'91TealRS

Well, I've whittled away at this for many months, first off, I'd change the O2 sensor, and fix any exhaust leaks ahead of the O2 sensor. On decel, you may be drawing in air and fooling the sensor.
My problem seems aggravated by a decel condition. When I first start up, and start moving, as long as I don't touch the throttle pedal, I can shift as many gears as I want (while idling), and the VERY FIRST push on the pedal gives NO HESITATION. Any subsequent shift, it is there. Also, if moving, I can put it in neutral (or hold clutch in) shut off, restart, put back in gear, and again, the FIRST accel is good. When I put back in gear, it was never in "decel", that is, let the engine slow the car.
Another cause is dirty intake valves, the theory is the carbon absorbs the fuel, leaning the mixture. Try some fuel system cleaner, I've used gallons of it!! LOL

'91TealRS

I ran this question on "AllExperts.com" about a year ago, and got a reply from an ASE certified mechanic who said he remembered these cars having this problem. He said he squeezed off the return line to run 60lbs to the injectors. Said it fixed the problem.

I haven't had the nerve to try that, any one have any thoughts?

Bob

85berlinetta2.8

i just put a new trans mount in my car, and it feels a bit less spongy coming off the line. im about to do the torque arm mount as well...

Rexer

Bob. Im very interested in finding out more about this as iv changerd nearly everything, im about to do the pickup and icm + coil and leads, i was starting to think it was fuel pressure related and was gona check the pressure with my friends guage, he is over in orlando at the mo on hols, so have you looked in to this fix of squeezing the return line?
iv been told by a guy over here from auto pontiac (uk mechanic/ pontiac guru) that all the 3.1's run like this. iv noticed that when you come off the gas it carries on fueling for a second or so, im told this is something to do with the cat and emmisions and they all do it (not a fault ?).
im sure it gets worse after it warms up ,
iv changed the tranny mount and swapped the crossmember so i could fit the poly one and it helped the drivability but didnt fix the problem,
thought it may be a vacume leak but cant find one.
also have changed the o2 sensor, that did nothing,
not getting any codes.

i should redo my original post and stop hijacking yours but i can never find anyone with a 3.1 with 5 speed manual with the same problem and now i have im gona hang around until one of us gets it sorted, hope you dont mind..
Nick

'91TealRS

Hi Nick,
Actually, the one thing I did that seemed to make a difference, was changing the PROM. Be careful to get one for a MANUAL transmission, not the automatic, like the shop did to me. That was a $400 (L220) education. The superceded part number is 16176864 (GM part number). Your original should have 5180 ARPL on it. I switched back to the original to compare, and the hesitation was MUCH worse. GM has discontinued these, but a few dealers may still have some stock left over and may be willing to part with them for less than the $97 list price.
The PROM for the automatic worked, but the idle was 700, and easier to stall, the shift light came on at speeds over 41MPH (converter lock-up signal), and if you started it by pushing, two codes would set(check engine light on).
Keep in mind, this will HELP the problem, not completely cure it. I still have a hesitation, just not as severe as it was.
Hope this helps,

Bob
----------
My trans mount broke completely, replaced it with a GM stock replacement.

sogabe

since u changed so much parts and sensor,
have u resetted the ecm?

unplug all battery cable for half an hour+.
then connect back and idle for 20min or so.

since u put lot of new parts maybe the
ECM havent arranged the variables
for the new parts and maybe needs some resetting.

i donno though... lotta trouble for u damn, good luck!

'91TealRS

YEP, done that many times, in fact, I had to get a new negative battery terminal screw!! LOL (An 8mm wrench works better than 5/16 for that)

Dizturbed One

this sounds alot like mine

i changed the 02, reset the TPS, did air filter, fuel, oil change...

i'm about to go test my EGR, but i'm not hopeful after reading this

i hope someone finds the problem

Rexer

back on the subject of upping the fuel pressure to 60 psi, whould this actualy work or would the pressure be too high? as soon as my mate gets back to the uk im gona rob his guage off him and see if pressure is my problem, im beginning to think my problem could even be the fuel filter as i havent changed it yet but i thought if it was than it wouldnt start and idle.... maybe im wrong on that one.
but if it is the pressure surely getting a new adjustable pressure regulator would be better than crimping up the pipe, again maybe im wrong on that one awell lol.

Nick

RBob

iTrader: (1)

From memory there was a TSB on hesitation. It stated to check the wiring harness around the coil bracket area. Apparently it would rub through on a bracket or such.

Another portion of the TSB recommended a newer MEMCAL (the PROM assembly). the required code was BAWX for 5-spd, and AZTY for the auto. This is one of the items '91TealRS mentioned.

The code (BAWX/AXTY) is on the small silver label on the PROM that is on the MEMCAL. Will need to drop the ECM down (under passenger side dash), pop the small lid off (2 screws) and can then read the label.

RBob.

Rexer

https://www.thirdgen.org/forums/v6/8...ml#post2915861

wow, finally im close to sorting out my problem.

NIck

'91TealRS

Thanks, RBob, Yes it is a BAWX Prom I have in there. It helped the hesitation, but did not eliminate it. I squeezed off the return line to get 60psi at the fuel rail. This actually solved the problem until the computer started learning the mixtures. I released the C-clamp I had on the return line, and the hesitation was back with a vengeance!! Seems the ECM wants to run this motor very lean......

The adjustable pressure regulator I ordered from Summit just arrived, and is actually just the cover with a screw in it for adjustment. You use the existing internals.

The thread that Rexer refers to was last posted to in 2002, but the issue of ignition modules was brought up, and seemed to solve most poster's problems. As noted, I replaced mine due to it burning out from exhaust being forced out the EGR. I just got the standard replacement from my local parts store. I believe it is a KEM brand. This was just last summer, I'm assuming if there was an update this unit had it. Do you think a high performance module is available?

I just discovered Moates.net where you can burn your own chip, I'm wondering if I can get results from there?

'91TealRS

Nick, this thread is 4 years old, but informative. The PROM issue was brought up, and is what I have done. I have replaced the stock coil with an MSD Blaster, enhancing my MSD unit. Never thought of relocating it to the driver's side. I just zip-tied it to the AC dryer.

Those are two good starting points, especially the PROM (mem-cal)

I'll keep you informed of my findings.

Bob

Rexer

so where can i get this new ecm if all the other stuff im doing dosent work? does anyone know somwhere that will ship to the uk?
nick

RBob

iTrader: (1)

You don't need the ECM, just the MEMCAL. For what the MEMCAL looks like see the sticky's on the ECM & DFI board here. You may already have the BAWX MEMCAL in there, so check that first.

To drop the ECM, remove the passenger side (driver side for uk'ers) hush panel. The ECM is the silver box sitting upright under the dash.

Push the bottom towards the front of the car, should be able to hear the velcro release. Once pushed forward enough to clear the pastic bracket pull the ECM down. On the cover will be a label that has the service # 1227730 along with the BCC.

Note the small cover along the top of the ECM. Remove the 2 screws and remove it. The long blue thing is the MEMCAL. Should be able to see a silver label through an opening and read the BCC.

RBob.

Rexer

just had a look and i have got BAWX 6865 in my ecm, so is this the updated one?
Nick

RBob

iTrader: (1)

I'm thinking that the return line is to be clamped off temporarily. The increase in fuel pressure would help in cleaning junk out of the injectors. The Multec injectors put into these engines are terrible. If the coils don't short out then they get dirty and the engine runs lousy.

Can get into PROM burning. Steep learning curve, but the results are worth it. Can change the fan turn-on/off temperatures. Change the SA tables, TCC lockup points, all kinds of stuff. The whole calibration is open. There is also a hac of the $88 code along with a definition file available.

RBob.

halftilt

Parhops I don't know my stuff, but I recently fixed a very, very similar problem by changing the blown IN-LINE f/p fuse that I completely forgot about in the engine compartment...

RBob

iTrader: (1)

Yes, it is the updated MEMCAL.

RBob.

RBob

iTrader: (1)

Yes, a good possibility, low voltage the to fuel pump can cause low fuel pressure.

RBob.

Rexer

Would the car still run with a blown fuel pump fuse? i would have thought not but is there not another way of the pump getting power via an oil pressure sendor? i will go and check it out right now.
thanks for the input,
RBOB thanks for that at least i havent got to go and try to find a new mmemcal, i can put the ecm back in its hiding place now.
il let you know how i get on with the fuse.
Nick

halftilt

It's strange because the in-line (20w)fuse in the engine compartment seems to do something only pump-related, while the one in the dash marked f/p is actually the pump power.

I was driving on a blown in-line fuse... whatever it does...

I believe I read somewhere that it was a fuel pump prime?

Rexer

the fuse on the inner wing/fender on the passenger side was ok, i pulled it with the engine running and it cut the engine out, put it back in and it started the fuel pump, so i guess thats not my problem.
Nick

biffx

Hey,My name is Will, I post on the net as BiffX, nick name I got when I was like 2. I am new to this site, i joined as soon as i saw that all of you were having the EXACT same problem as me. I have a 3.1 and a 5 speed. I replaced the 2.8 that came in it. Its a 1988. Like all of you I have replaced countless components, and no codes I think I'm gunna stick with you guys.

1988CamaroSC

iTrader: (2)

my problem sounds different than yours, but my car, ill be going 20+ mph and it runs GREAT, then i get down to like stopping at a traffic light, the rpms drop twice down to like 400-450, vibrates like hell, and it usually recovers itself but like in parking lots or in traffic, she stalls right then and there, but starts right back up like nothing happened, and sometimes it doesnt want to idle, it drops down low again and ive got to step on it for like 10 seconds to keep her running. now heres the q, someone told me the torque converter could be stuck in lock up? replace the tc solenoid that activates the lock up? oh its got a fairly rough idle too, you would think it has a mean cam, but its stock....

Rexer

we should make this the oficial 3.1 problem thread.

well i got all my parts from my mate who was on his hols in the states so will be getting tucked in on saturday, will let you know how it goes.
Nick

'91TealRS

Hi All,

Well, the adjustable FPR can only be adjusted with the upper intake manifold off, as the screw almost touches the bottom of it. This unit was meant for a V8, but it fits these just the same. I set it up for 65psi with the manifold off (fuel pump on for 2 sec), and after putting everything back together, it was running 70psi. Vacuum does not lower the pressure, must be too much spring pressure for the vacuum to overcome. Once the ECM learned everything, the problem was back.

One thing I did learn, is that you really don't need to spend the $80 on an adjustable FPR (which is just a cover with a screw in it)(which may, in fact, lead to vacuum loss). The spring rests against the top of the stock unit, with no tension after the screws are about half way out (about 3/8"). You can shim it up with washers, and get the same results, you just won't be able to adjust it while it's running. Not to mention risking stripping out the aluminum fuel rail . I was all paranoid about the spring flying out, so I removed the fuel rail, and C-clamped the unit to it when the last two screws were out a little. Once the screws were out, the clamp barely held any resistance.

I think I'm going to return to the stock unit, the higher pressure doesn't seem to be helping performance any, although at high speed, the motor doesn't seem to be working as hard. It seems to idle a little rougher now, also. It can't be helping the fuel economy any, either.

Thanks to RBob for the info on the PROM, I also have the BAWX 6865.

Sooooooooo, it seems we are back to the beginning, same problem, no known fix. I really think the issue is in the PROM and related electronics, as the replacement PROM produced a much less severe hesitation as the original which was ARPL 5180.

When you hack into the code, do you burn your existing PROM, or build a new one? These PROMs are in very short supply, and I don't want to lose a perfectly good stock unit. Maybe I could modify the ARPL 5180?

Thanks to all, maybe the answer is still out there.

Rexer

Right, im doing this one step at a time to see if i can isolate a cause, iv done the ht leads(plug wires) and no change, my fuel pressure is reading 35psi on idle a slight touch or the throttle rises to 40 and back to 35.too low?, so im gona change the filter and see what it is after that.
il keep you posted
Nick

Rexer

ok, my mistake, fuel pressure was 45, i forgot you have to disconnect the vacum hose to the regulator. did that and it read 45 psi at idle so thats ok. changed the ignition coil and still the same. it may have smoothed out the idle a tad but apart from that no change.
next up is pickup coil and ignition control module and after that if its still the same then this v6 is gona get ripped out and a 5.7 is going in with a carb.
Nick

'91TealRS

I have a feeling that won't fix it, but I would be anxious to find out. After you reconnect the battery and it has time to "learn" the settings, the problem will probably return, at least that's been my experience.

I bought the "adjustable pressure regulator" from Summit, and all it is is a cover with a screw in it to adjust your EXISTING regulator. They send a survey in an e-mail with every order, and I expressed my dissapointment with the incorrect and deceiving description. I got a phone call from them, they checked the part, and agreed with me, and I am getting a refund. They are adding the fact that you use your existing regulator to their product description. The "adjustment" screw was not very effective, 1/4 turn (or less) increased the pressure from stock (45-47 psi) to maximum pump pressure (70psi), not much of an adjustment.

Anyway, while running 70psi, the problem was solved until the computer compensated for the attempt at making it run richer, and the problem returned. You can accomplish the same thing by adding a washer or two to the inside of your stock unit, it is a hassle, though, as you have to remove the upper manifold every time. Not to mention the wear on the threads in the fuel rail from removing the cover every time.

Try this little test: Start the car, and put it in gear WITHOUT touching the throttle. Let the car idle along. Then step on it. You probably will have NO problem. BUT, the next shift (change), and all subsequent shifts, will have the hesitation. Stop the car, shut it off, and repeat. Should have the same results, the VERY FIRST press on the throttle pedal is smooth as glass, but after that, they are all bucking broncos......... That is how mine is, I bet yours is too......

This really has me stumped........

Rexer

when i first got this car i noticed somthing wierd, when you come off the gas it takes a 3 to 5 seconds for the car to start what i call engine braking, ie,where no fuel is going in, i was told that this is just the way they are and had something to do with the cat, im nearly convinced that this is part if not all whats causing this,

it seems that if i put my foot say half throttle (il use 2nd gear as and example) it will be fine untill the engine comes off load, you know where your shift light comes on, if you change throttle position you will get that bucking feeling. so it seems it only happens on a throttle position change, its fine if you nail it full throttle on one hand and at the other end of the scale, just rolling along in 2nd in traffic is a horrible experience.

so im gona change the icm and pickup but thats all i can do as iv done most other things.

if i already have the updated prom then i guess im just ****ed cos i cant work it out, me too it has me stumped.

'91TealRS

Seems like it is idling too fast? I removed the plug over the idle screw (which you are not supposed to do) and turned it down. I had the same problem with the RPM "hanging up" (not braking). A lot of smog motors do this, as that is the most smog-producing time (between shifts). The old PROM would idle this motor around 1100 RPM, I thought that was too high. The new PROM (the one you have) idles it at 900 with the idle screw turned way down. If you turn it too low, the blade will hang up in the throttle body, and not idle all the way down unless you "snap" it.

I have heard MANY opinions on adjusting idle speed. Seems the best way is to close the IAC valve all the way (do this by jumping the ALDL terminals to diagnostic mode and turning the ignition on) The check engine light will flash a code 12 three times, then flash any other stored codes three times. This will also turn on the engine fan, and close the IAC pintle. Then turn the key off, remove the jumper, unplug the IAC and start it. Adjust the idle as low as it will go and still run. I tried to get mine to 750, but it wouldn't go much under 900. Then shut it off, plug the IAC back in, disconnect the battery for more than a minute, rehook the battery and re-start. It will need to re-learn everything, but the idle may be slower. It's worth a try, you think? Keep track of how many turns you turn it, so you caqn return to stock if you really want to. You will need a T-25 torx bit.

Good Luck

'91TealRS

I JUST REMEMBERED...... a long time ago, when I was having injector problems, it would act as you are describing, at low RPMs it would jerk, and jump, you had to keep it gassed and revved to keep it smooth. The new injectors solved that problem, I realized it after I wrote you, I drove to work, and slowed down for a turn, didn't have to shift out of 4th gear. Ran smooth all the way down to a very low RPM. The way it was before, it would jerk.

It was running VERY rich at that time, a few injectors had resistance readings of 8ohms or less. This rich condition plugged up the cat, and all kinds of problems arose from that!!

I also had the throttle shaft re-bushed, thought it was a source of vacuum loss, and could make the throttle "stick" and jump, but it is definitely a hesitation.

I would recommend adjusting the idle speed down a bit, also look at the metal tab that touches the idle screw, is it bent? Mine was bent forward a bit, so I straightened it to 90o, and HAD to turn down the idle screw. As I said before, keep track of the number of turns, in case you want to return to original setting. I have played with mine so much, I forgot where it was originally. After adjusting it, re-set the computer by disconnecting the battery for a few minutes.

GOOD LUCK

'91TealRS

I did it again today, I shifted to 2nd without touching the gas, it was idling fast (1200), when I hit it the first time, it was smooth as glass. The next shift was rough. Seems to be not too bad, though, sounds as if yours is a real bear.

I don't know how old you are, but if you remember the American cars of the early 70's were NOT available with a manual transmission, automatics were all you could get from the factory. Seems the cars polluted when the engine RPM was dropping between shifts, and the manufacturers decided to not fix the problem, just not offer manual transmissions. "They'll buy what we build" was their motto in those days. Of course, those were carbureted, the ones we are working on now are injected, but I think that has something to do with our problem. The "decel" condition is rich, and the computer cuts the fuel during that condition to save the cat from overheating. Maybe the resulting lean (very) condition causes our hesitation problem. Seems that if I shift and let the engine pull before stepping on it, it doesn't hesitate, Maybe if there was a way to reduce the vacuum signal to the MAP? When it's above idle speed with closed throttle, is when the problem occurs. The computer learns the idle from the TPS signal, and knows the RPM, maybe vacuum is not a a factor. I'm leaning toward re-programming the computer, but that is a can of worms I don't think I want to open..........

Do you have oxygenated fuel in England? We here in CA. have it year-round now. MTBE is poisoning water supplies, so we are phasing in ethanol, maybe that is part to blame?

Hope my findings interest you, and we can both solve this.

Rexer

you know what, i was gona mention that i had been down that road about american cars and manual transmision, i do remember that all american cars were manual, lol i just thought you were all lazy , since i changed the coil it has improved a bit, the bucking is not as harsh but still there. im gona do the icm and pickup but im not expection much out of that, im glad you mentioned the injectors as thats a fairly simple thing for me to sort as i have a shop not too far away that uses ultra sound to get them up to spec, not sure how much new ones will cost over here as we get ripped bad for stuff like that, maybe somone will send me some from over there marked as a gift so i dont get stung in import tax, i can pay with paypal, Fastrs off this forum did it for me when i needed a heater core, i got quoted £120uk for one and i think he sent it to me for $40 thats like £100uk off ..nearly $200us ....see what i mean? lol.
so if i was to test them on a metre, what readings should i be looking for?

oh i forgot, on the subject of gearbox's, that was my first thought when i got the car, the box has gone or the prop has play in it, thats what it feels like, iv changed the trans mount, i actually changed the whole crossmember for an earlyer one that has the 2 little donuts and a big mount. swapped them all for ES poly, did the torque arm mount in ES poly aswell. then i moved on to the engine bay. i have changed ........

MAP SENSOR
TPS
INTAKE GASKET
PLUGS
WIRES (TWICE)
CAP
ROTOR
O2 SENSOR

i wish i had a fault code to find this problem. THIS CAR HAS ONLY 60.000 MILES ON IT GRRRRR lol

Nick

'91TealRS

They should all be 12 ohms resistance when measured with an ohmmeter.

But do change the icm (ignition control module). Use the Delco D1943A. That is what the part #16140039 crosses to. I changed my module after the cat plugged up and spewed hot exhaust out of the EGR. I went to the parts store and just got the one they listed. When I recently cross-referenced that part number, it comes up as "aftermarket", it doesn't cross to a Delco anything. I bought a new module, but haven't put it in yet, as I have an MSD, and thought the ignition was strong enough. After thinking about it, the icm sends the RPM info to the computer, maybe that is the problem. I will change this soon, it's been a bit hot here lately, I'm waiting for cooler weather

I bought at set of "remanufactured" injectors from a place in So. CA. for $229 (about L125) from this place:

TPI Fuel Injectors - OEM Fuel Injector Sets

I got the 5235136 set, which is the right flow rate. They are all exactly 12 ohms each.

Good Luck

Rexer

Bob, the icm i have got is made by GP SORENSEN part no. EL128 and pick up is EL357. my friend got them from american motorsports American MotorSports - High Performance Parts and Service
do you know if these are any good?
Nick
----------
Bob, my mate got the icm and pick up for me from American motorsports

American MotorSports - High Performance Parts and Service

made by GP SORENSEN icm part no. is EL 128 and pickup is EL357
are these any good ?

Nick

'91TealRS

Well, Nick, I did extensive cross-referencing, your EL128 crosses to 3 Delco numbers (D1906C, D1943A, D1960A). My original part was a KEM brand, and the Delco D1943A (the recommended part) crosses to a (KEM)E245, and your GP EL128 crosses to a (KEM)E244. The KEM part I bought is a E243X which doesn't cross to anything, which is why I am replacing it with a Delco part.

I am only buying Delco parts at this stage, as I want only the best, and/or the correct product. That way I won't get the wrong item, and create doubts about it's performance.

I don't know of GP/Sorensen's reputation, seems they are the same as Standard Motor Parts here. Also Borg-Warner came up on one of my cross-reference searches as sharing the same part number.

Here are some links to the searches I did:

AC Delco

Interchange

Below I tried to copy and paste the chart:

Parts Previously Entered
Entered
Part No KEM
Part No Part
Description
EL128
GP/SORENSEN E244 ELECT MODULE
EL357
GP/SORENSEN E248 PICK UP COIL
16140039
AC / DELCO / GM E245 ELECT MODULE
D1943A
AC / DELCO / GM E245 ELECT MODULE
E243X
KEM E243X PV ELECT MODULE



AC Delco

1992 PONTIAC FIREBIRD 3.1L 189 cubic inch V6 MFI (T) Control Module


Rock Auto (the link above) seems to be a pretty reasonable supplier, however, they do caution about overseas usages, as emissions requirements are different for exported vehicles, and the part may not fit. Seems pretty reasonable, $49.99 (about L27.77) but I don't how your customs taxes work. I have relatives in England, I remember when we sent our Christmas gifts, we had to declare the value, and/or whether it was a gift. Are you near Chislehurst (spelling?) in Kent? My mum has a cousin there.

Here's another link:

http://www.partsamerica.com/ProductL...2fControl+Unit

Hope this helps

Rexer

small world mate, im about 8 miles from chislehurst and drive threw there daily, i pick up busses from bromley which is just round the corner(wrecker driver) ,i live in dartford in kent. well funny that. i bet if i said i knew somone in the states chances are you would live 2000 miles away from them , tis a small island is tha uk lol.

so what is the difference between all these modules? i dont have to worry about the emissions over here (cat removed)

Nick