Agreed. Either due to haste, oversight, or whatever, it seems that some of the details are slipping through the cracks. That might not be as much of an issue with a 1995 Ford Escort, but ThirdGens are circling back to becoming collectibles, and deserve a little better attention.

 

Right, some respect for still being here--and for someone who has taken the time and money to keep it on the road for over thirty years. In fact, whenever I would take it to a shop I would wash it and vacuum it hoping to get some respect for the car, and hoping they would not treat it like just some old beater of a car.

 

Anyone have one of these brackets they don't need anymore. It's on drivers side, gets attached to the front valve cover bolt and is meant to hold wires. Certainly willing to pay for the part and shipping.

 

I would suggest some nylon ignition wire separators by Taylor. I have them on 2 cars and I love them.
I would also recommend buying 2 sets since there never seems to be enough in one set...

https://www.summitracing.com/parts/tay-42700

 

'Sorry I don't have one of those brackets, and mine is long-gone, but I really don't need it and you may not either. I know of only one wire that was routed that way, and it's the Temperature sending unit wire for the gauge. I re-routed mine so that it no longer goes over the valve cover and hot-as-hell exhaust manifold. It now routes along the top of the driver-side frame rail and directly to the sending unit in the cylinder head. It has the black split tubing over it and looks like it came that way from the factory even though it didn't. That tubing was zip-tied to the existing lights harness tubing...

 

That was not used on all ThirdGens, and will probably not be easy to find at a recycle yard. An alternative would be to fabricate a replacement. It looks relatively simple.

 

I have made some progress and have some good news. Did a lot of wire maintenance to get the spark plug wires, coolant fan switch wire, and temp gauge wire away from these aftermarket headers as much as possible. T.L. I am liking those Taylors. Then my husband and I set the TV Cable. Wow--a world of difference. I was really worried the transmission had been burned up--but think its ok. I think the tv cable could use some fine tuning. Seems like I am getting some early shifts (2nd around 12 mph and 3rd at around 25 miles mph). Also doesn't seem like I am getting the downshifting when braking.

The other good news is that I have no SES light, and no codes. That's HUGE!!!!

So with the wires tucked away, and the TV cable adjusted much better, we were able to start and drive the car (WOOHOO!) for the first time since picking it up. It seems to crank a little longer than before (3-4 seconds), then starts, and stumbles, coughs a bit (2-3 seconds), and then settles into its fast idle (around 1800 rpms). Left it there for a couple of minutes, gave the throttle a bit of a tap, and it seemed to drop down to the second step of fast idle cam (idling now at about 1000 rpms). Then after another minute or more, hit the throttle again fairly hard and it stumbles a bit and the idle dropped to 450 and settled at about 500 rpms (which is spec per the hood decal).. That feels a little low to me (but spec). I know that I used to tell mechanics to set the idle a bit faster than spec, bc the idle just seemed a bit smoother to me. Any harm in that? Will increasing idle speed affect the emissions?

All in all, not bad, but again, think there's some fine tuning to do. Shall I just increase my curb idle speed, or should I see where the IAB valve, and Idle mixture screws are set. I did measure the MCS travel and it does look like it's at 1/8. Would appreciate your thoughts.

Also, the fuel smell is gone. The garage always smelled like gas especially after a drive. Really don't smell it at all. I am guessing then the charcoal canister system is working!

I would try and get it through dmv, but the car still pulls hard to the right when braking, and when I hit the brakes hard the right rear wheel locks up. I have now starting reading lots of posts on brake work, and I need some guidance. Is this something I can tackle. Is it work that you need a lift for. I don't know anything about brakes, and the thoughts of not bleeding the system correctly sort of terrifies me (however 8 months ago I knew nothing about the cars emissions system, and now know every component and what it does, and knew nothing about quadrajets, and now have a backup quadrajet halfway through a rebuild). Again, would appreciate some guidance. Thanks.

 

I like my cars to idle at 650 RPM in gear (with an automatic) which is around 800 in Neutral. It won't hurt anything. Of course there is a limit. If the throttle blade is too far open, it will be out of the idle circuit (past the transfer slots) and into the cruise circuit causing a rich idle. Advancing the initial timing increases the idle speed without having to further open the throttle blade. Additionally, an idle speed that is too fast is harder on U-joints when going into gear from Park or Neutral. I make 800 my limit.

The early shifting could be caused by the TV cable being adjusted too tight, but be aware that too loose is what burns up the transmission.

Does the car have drum brakes on the rear? If so, the lock-up could be a result of them being out of adjustment (too loose). They should put just a slight drag on the shoes that you can hear when spinning the wheel by hand...

 

Don't need a lift for brakes, just need to jack it up high enough to take the wheel off. Brake jobs are pretty easy, just take off the old stuff and replace it with the new stuff. Might want to invest in some flare nut wrenches if you're doing the soft hoses as well. You will need a helper for bleeding. If you have drums in the back, you might try an adjustment first.

 

Another consideration is that it the vehicle has not been moved/driven for months, the rotors and/or drums might not have completely clean surfaces.

 

the hoses are likely causing the pulling when braking

best to replace them. re-man calipers and wheel cylinders are pretty inexpensive too and usually a good idea. RA may have everything for less than your local place.

you can gravity bleed by yourself as long as you're careful not to let the master cylinder reservoir run dry.

start a new thread if you want when you get ready, just let us know.

 

I had great hopes of finally getting this car back on the road, tagged and registered. I had a lot of confidence that we had learned enough and had enough support on here that we could really get this carburetor tuned in, and running really well.

We had also been reading a lot about brake repairs. Again, after a lot of reading we felt fairly confident we could figure out what was going on with the right rear brake and once that was resolved, could then tackle replacing all of the brakes. We bought a floor jack and 3 ton jack stands are on their way.

….and then…..yet again… it happens. We drop the car off at the transmission shop (a shop we fully trust, and which had previously reset the TV cable perfectly) for two hours, so that they could fine tune the adjustment of the TV cable—that’s it. When I dropped the car off, I thought, ok, the car ran pretty well. Idled well, albeit a little low for me, but well. No problems.

We go to pick it up two hours later, and the repair technician (unfortunately the gentleman that had worked on the car before was on vacation) told us he noticed a misfire of the engine. Didn’t think much about it bc the car ran so well on the way down there. Also said he had to adjust the TV cable about a half inch or more from where it was (much looser than where we set it using the FSM, and where it was shifting fairly well but a bit early).

Got in the car, and didn’t let it fully warm up, so it’s sputtering as I pull out, and I thought it’ll warm up in a mile or two. Well, a mile or two down the car the car is really struggling. Sputtering, misfiring, like a spark plug, or two, is not firing. Heard a few fairly loud clangs from the transmission area on the way home. After a tense ride, got it home. Took a quick check, actually hoping to see some burnt spark plug wires, but nothing obvious. Closed the hood and haven’t had the heart to look any further.

I was and still am ready to throw in the towel. When I finally had some hope we could finally get this car right again, this happens. I am not saying the trans shop did anything. I don’t know that. They are hands down the best transmission shop in the state. Everyone thinks so. I also understand that there is always something going wrong in older cars. I get that. I suppose something could have burnt up, or melted after I parked the car at the garage and left. I simply don’t know, and have no desire whatsoever to argue with them about it

My husband says don’t give up—but feeling quite defeated at this point. I guess my biggest concern is the transmission. However to figure out if the trans is fried, we will first need to be able to drive the car, and thus need to figure out why it is misfiring, so badly.

Any help on where to start to diagnose the misfiring, would be greatly appreciated. Can you test spark plug wires and how. What else would cause such misfiring. Could it be distributor related.

Also, can someone tell me what the gold thing is in the picture below. I am thinking it is the oil pressure sender. I ask because it looks new, and since I got the car back from the mechanic, I have noticed lower than normal oil pressure, via dash gauge. In the past, IIRC, oil pressure would be a bit above or below 30. Since I got the car back it has been mostly below thirty, and the other day, went to about 15, if not lower.




Also, when I was reading posts this morning on low oil pressure problems, a couple of people mentioned a ticking sound. I have a ticking sound. Had it since some repairs about a year ago. Nobody explained how the ticking is related to oil pressure, or why it ticks. Can someone enlighten me please.

The next picture is the throttle cable. As you can see it takes a hard right around that bracket. The sheathing has some wear there where it hits the bracket. Is this how the throttle cable is normally routed.


Finally, there are a couple of pics below of my tv cable. As you can see the part of the cable that gets moved when you set the cable is out about ¾ inch. If you look closely, you can see a darker and lighter shade on that part. Right where the dark and light sections meet is about where we had the cable set. The second picture is me lightly pressing down on the cable to show how loose it is. If I lightly press down, I get about ¾ inch play.



This just does not seem right to me. Seems too loose. When we set if using FSM, it might have had about ¼ to 3/8 inch play, and became really taut at WOT. Can someone give me an idea how taut their cable is, and whether this looks right. I also wonder whether if a car is misfiring so badly, whether you can properly set a tv cable.

Sorry for the long post, but I got a lot going on here. Any and all help would be very much appreciated.

 

Yes, the gold thing is the oil pressure sending unit. The ticking noise could be a lifter not pumping up, OR it could simply be a header leak. Personally, I would adjust the TV cable according to the FSM. Too loose and it will burn up the transmission. I know how discouraging these things can get, but rather than give up, perhaps it would be a good idea to just take a break from it over the winter, sort of regroup, and get back to it in the springtime...

 

Here's how My throttle cable is routed.
Looks like you have an extra bracket attached that isn't being used for anything; the part your throttle cable is up against...

 

Perhaps you're right T.L. Actually, it sounds like a really good idea. Some good news--I'm just about finished rebuilding my back-up carburetor, and it has gone pretty smoothly. Will finish that, and take a break. I'll hopefully be back in the spring, and things will go a bit better. Thanks.

 

a mis-fire on the left bank, where the O2 sensor is, will cause a rich condition as the feedback system attempts to adjust the mixture richer in response to a 'perceived' lean condition. This will gradually foul up the other plugs and cause the motor to run progressively worse.

Best to pull the plugs and clean or replace them all. Find the mis-fire and fix that.

for the cable, have someone hold down the throttle all the way and see how much slack is in the cable.

that's normal routing for the throttle cable.

that 'extra' bracket should be for the cruise control

 

Me again. I did find the misfire problem and fixed that---spark plug wire had come off the distributor. So then we moved onto the brakes. We rebuilt both drums with all new parts but the wheel cylinders keep leaking at the connection in back. Going to post on the brake forum, so would appreciate any help.

 

BIG BIG NEWS!!!! The car passed inspection. We are now, finally, legally tagged. We had some doubts going in. We had just finished our drum brake repair--replacing the trailing brake lines, the wheel cylinders, new shoes, new springs, and new drums. Our first big repair.

As for emissions, it had failed 6-8 times in the last 2 years. The plan was to reinstall the original carburetor (rebuilt) and original intake manifold, and do our best to make sure all the sensors and switches that send info to the ecm were working. The plan worked!!! The numbers were a bit surprising. While DMV kept the readout sheet, the best we can remember is that HC number were close to the limits. The low rpm reading was around 200, and the high rpm reading was 218. The limit is 220. Whew--close call. The CO numbers were surprisingly low. Each close to 0. The numbers were surprising bc it usually failed due to CO, and would generally pass the HC with much lower numbers. No idea why the HC was so high. Any thoughts on that would be appreciated.

Now, we have plenty more to do. Got a bit of a leak in the top radiator hose at the radiator end. Have tried to reseat that hose, but just might have to replace it. Also, we think the front brakes need work now. I'm getting this vibration when braking hard. It seems to vibrate in the front end and it feels like it spreads from the middle of car towards the wheels. No idea what that is--but thought replacing the front brakes would be a good start--especially since the rear brakes were such a mismatched and leaking mess (had a SAE wheel cylinder going to a metric brake line fitting, and a metric wheel cylinder going to a SAE brake line fitting). This job will be another first for us---never worked on disc brakes before. Got a lot of reading to do before we start.

Also, the car is still stumbling a bit at start up. That is, when I start the car when cold. it stumbles for about 5 seconds then catches on and starts its fast idle. The choke seems to be working well. I let it idle on fast idle for a minute or so and then kick it down to the middle idle speed. After two or three minutes, I kick it down again and it drops to its curb idle speed (have also just let it idle after kicking it down to the intermediate idle speed and it lowered the idle speed to curb idle by itself).. Any thoughts on why it would be stumbling on start up. Also, do you need to kick it down from fast idle to the middle idle speed by hitting the gas pedal, or should the choke do that itself. Same question for dropping down to curb isle speed. Should I manually kick it down by hitting the gas pedal or let it drop on its own.

I did purchase a scanner. An autoxray 6000. Will try and do our first scan next week to see where things are at. I will let you all know.

Anyhow, I am thrilled to be able to drive the car again. I can't thank you all enough for all the help you have provided so far. You have been so kind. Thank you, thank you, thank you!!!

 

Great to see good news. I know it's been quite a journey for you...

 

What State are you in, OP?

 

If it has been running rich (high CO) for a long period of time the oil in the crankcase can become contaminated with fuel. Contaminate oil fumes get pulled back into the PCV to be burned where they generate excess CO. I have seen a fresh oil change get vehicles over the HC hump.

 

Yes That Is The Normal Operation

 

I'm back!! Took a few weeks off to bask in the glory, ie breathe a sigh of relief we completed the rear brake rebuild, the car passed emissions and is now legal. Would like to now start thinking about a front brake rebuild (different thread) and fine tuning the carb. So, I am back for guidance from the carb gurus. If I should just post this on a new thread in the carb forum, please let me know

The car runs fairly well. Seems to be lacking some power and responsiveness, and still have a stumble at start-up. It starts up after 2-3 seconds of cranking, stumbles for 3-4 seconds, and then catches. Goes to a high idle of about 1800. I leave it there for about 5-6 seconds then can kick it down to, I guess, the middle stop on the fast idle cam, and then wait a couple of minutes, and then kick it down again, and it lowers to an idle speed of about 600. So the initial stumble is really the only issue I am seeing. I've read enough to know that we need to take the air cleaner off and see what the choke plate does on start-up. We will do that in a day or so, and I will let you know.

In the meantime, I have some scan results I would appreciate your thoughts on. The readings were as follows:
Battery Voltage: 14.2
Coolant Temp: 197.6 (have a 195 thermostat)
Vac Sensor: 4.09 volts
Throttle sensor: 1.96 volts
O2 sensor: 365 mVolts (did also get a 13 error code--but we have since cleared the codes thinking that may have been an old code--we'll see on that)
Mixture Control Sensor: 72.9%
Engine RPM: 600
Baro Pressure Sensor: 4.7 volts
O2 CrossCounts: 6 (no idea what this is????)
Rich Lean flag: Lean
Loop status: Closed
TCC: Not locked
High gear: Not engaged
Air diverter: Solenoid On (not sure what this is--do not have the AIR system on car)
Air Switch: Solenoid off
AC Clutch: Disabled (??)

Just wanted to get your thoughts on these numbers and whether anything jumps out at you. The two that I have been wondering about (beyond the 13 error code which we follow up on with another scan to see if we cleared it) are the MCS at 72.9% and the TPS at 1.96 volts. The scan was done with the car warmed up to operating temp, at idle, in park. Also used a timing gun for the first time and it appears to be at or slightly above 0 (had the 4 prong plug with the 4 wires that go into the back of the distributor, unplugged-per the directions on the hood.


Some of my questions are:: Should I retest the TPS with the multimeter, and if so how? Should I try and adjust the TPS, or start to figure out where all the other carb adjustments are first. I have read an earlier post by naf that outlines a process: Set lean stop, set rich stop, check idle mixture screws and IAB. He then says to follow these steps: Set timing, Set curb idle, set TPS voltage, adjust dwell, check for vac leaks, readjust curb idle and TPS if necessary, and follow thru on choke and fast idle adjustments. Should I do all that before attempting to test or adjust TPS.

Also, can I use the multimeter to re-test the MCS %, which I believe is dwell--is that right?? Do I stick the probe somehow onto the green dwell connector and then to any ground?

Finally, I presume the Rich Lean Flag reading indicates it is running lean--and this lead me right back to checking all the carb adjustments---right?? Thanks for any and all thoughts.

 

600 RPM at idle is awfully slow. Should be at least 750 in Park/Neutral fully warmed up. Should drop approximately 150 RPM when dropped into gear...

 

Thanks T.L., I have been wanting to raise it to even out the idle a bit--but kept hesitating bc the hood spec says 500. I will go ahead and give it a try. Hood instructions say to disconnect the idle solenoid (meaning I guess the idle stop solenoid) and turn the idle adjusting screw. Is that it, nothing more to it? Also what would your suggestion be on timing. I have read going to 6 BTDC peps the car up a bit.

 

The only carbs I have worked on are non-CCC, so I would follow the instructions you mentioned. You should be able to bump it up to 750 RPM in Park/Neutral. You don't want to go too far, because then the throttle blades would be past the transfer slots, causing a rich idle.
Isn't 6° initial advance the factory setting (I don't remember)? ...

 

An '86 305 carbed engine probably had a VECI label on the radiator support with the alpha code "YCM" or "YCX" and a matching vacuum hose routing label. Follow those specifications for setting base timing and hot curb idle. Bumping the base timing to 6-8° may not be a problem, especially with ethanol-blended fuels.

It is also likely that the carb had a throttle kicker solenoid on the left side. If that is present, adjustment of the base idle position (hot engine, wheels chocked, in DRIVE) should be for 500 RPM with that solenoid deactivated. The curb idle with the solenoid active is also shown on the VECI label. If the solenoid is missing you can bump that up to the second step (probably 650 RPM) on the label, but may experience some run-on (dieseling) when the engine is shut off hot, and/or may not have a sustainable idle when the A/C compressor is operating.

Sofa provided this photo earlier, and the throttle solenoid has been marked:



One of your previous posts (#173) indicated the throttle position sensor at 1.96V. At a closed throttle position, that is WAY too high. Try to adjust that to 0.48V ± 0.04 instead, and that could provide you with a lot better performance. That requires some less common tools, and procedures. The OTC 7667 tool set, KD 2776, or OEMTOOLS 25062 should get it done if you don't already have the 2.5mm thinwall hex.

 

Thanks Vader: Good info. Didn't realize the sticker gave directions for when solenoid is active, will have to look a little more closely at it.
On the TPS, I was almost certain that was way, way high---but I am so new to all of this (although as I mentioned above--I have now rebuilt my first quadrajet--not the one on my car) I had to ask. I do have the tool for the TPS adjustment. Can I measure voltage out of TPS connector with my multimeter to at least get it close. If so, could you explain how I would do that. Do I just insert the probes into the top two holes.
Also I have this "vintage" analog dwell/voltage/rpm meter coming from ebay.in a few days. Thought I could use it to check dwell, and TPS voltage, and their fluctuations (they are both supposed to fluctuate a little--right?? Also, I am hoping I can first figure out how to use it. In reading some of the instruction manual, it says for dwell, to hook it distributor or ignition coil--but I know we have the green dwell connector in our cars---do you know if I can use that instead.
On timing I have read several times people bumping their timing up to 6, or even 9. Is there anything special about 6 or 9?? That is, could I bump it up to 4, to see what it does, and to better avoid any pinging.
Sorry for all the question, just trying to learn.

 

TPS ADJUSTMENT

1. Start engine and allow it to reach normal operating temperature;
   
2. Set engine timing at the specified RPM;
   
3. Set base idle speed with the A/C off and idle speed solenoid disconnected;
   
4. Turn off the engine;
   
5. Insert the probes of a digital voltmeter in terminals ‘B' and ‘C' on the TPS connector (center and bottom terminals). You may have to insert a paper clip or similar object into the rear of the connector to make contact;
   
6. Turn on the ignition but do not start the engine. Read the voltage of the TPS. Remove the top plug (19) and adjust the TPS screw (18) to obtain a reading of 0.48VDC across the terminals.
   
   NOTE - If your meter probes are reversed, the reading will be -0.48VDC. The important factor is the number.
   
   
7. Replace the hole plug in the adjustment screw hole when the position is set;
   

 

A dwell meter can be used to check ignition point dwell, and set the mixture control idle air bleed on the E4ME. It is in essence a duty cycle meter, displaying the relative time of a signal being "on" compared to it being "off" (as in distributor points being opened and closed). A multimeter with a duty cycle function or oscilloscope would be just as effective.

1. Connect a dwell meter (or other instrument) to terminal ‘B' on the enrichment solenoid connector, and the instrument ground connector to reliable engine ground;
   
   
2. Start the engine and allow it to reach normal operating temperature. Start the engine and reset the base idle if necessary. The dwell meter reading should vary while this is occurring, or the oscilloscope square wave frequency (pulse length) should vary;
   
   
3. Set the parking brake, block the drive wheels, and place the transmission in DRIVE for an automatic car, NEUTRAL for a manual car;
   
   
4. The dwell meter reading should fluctuate between 10̊ and 50̊ on the 6 cylinder scale, while an oscilloscope or duty cycle meter should indicate a 15-85% duty cycle. Adjust the idle air bleed valve screw (12) in 1/8th turn increments to obtain a dwell reading between 25̊-35̊. The optimum setting is 30̊ (50% duty cycle), so get as close to this as possible. Adjust the screw only a little at a time and allow the system to react between adjustments;
   
   
5. If the desired reading is not attainable through this method, the idle mixture screws will have to be adjusted (87). This will require removal of the carburetor and cutting the throttle body away around the steel plugs. Then reinstall and adjust the idle mixture screws evenly , then adjusting the idle air bleed screw as described above to obtain the correct readings.

 

Begin with the base timing set at the original specification. Once the rest of the system is adjusted correctly and running properly, the base timing can be adjusted to your liking, within reason.

 

Thank you so much for the detailed step by step replies Vader. Very very helpful. Really appreciate you taking the time. Thank you
Adjusted the idle today, and the idle stop solenoid is there but doesn't look like it is working. So, I set the idle at 600, until we have a chance to look at the idle stop solenoid. It evened the idle out a bit.

We checked timing the other day, so then I went to adjust the TPS and wouldn't you know it, it has a plug. The LAST thing I want to do is drill into this carb---makes me very nervous---but I guess that's what I will have to do. If there is any other good way to get the plug out--please someone tell me (I have read several posts saying when you drill to use left hand drill bits, and a mention or two of a slap hammer).

Anyhow, we thought it would be a good idea to double check the TPS voltage with the multi-meter just to make sure we didn't get any funny numbers from the scanner (it was only the second time I had used it). Then thought we can do another scan and maybe also get some live readings while going down the road to see what the reading are. I sure hope all that leads to me saying-----Oh the TPS is fine. Would hate to drill only to find out I didn't need to. I would almost rather remove the air horn (maybe with the carb on the car) and replace the TPS unit, as opposed to drilling.

My only question today is: Is it possible the connector that plugs into the TPS unit is bad, or shorted, or something which would cause such high voltage numbers, or is more likely the TPS unit is bad, or that it just needs adjustment. Is there a test to determine if the TPS unit is bad, as opposed to misadjusted?

 

Best guess is that it simply requires adjustment. If you were so lucky that you put in the TPS and it was adjusted anywhere near where it should be, you should go buy a lottery ticket and extend your streak. The plug above the TPS adjustment is an anti-tamper plug, and we thoroughly intend to tamper with it. There is no other need for the plug, although I have read/heard that it is installed to prevent the adjustment from wandering in normal use, which is not the case. Drilling is not against the rules. Just center a small drill bit and avoid drilling the carb body itself. Drill the small hole, then thread a small sheet metal screw into the plug to provide something to pull. The plug should lift out without much struggle using pliers or something similar. If the open hole concerns you, another plug (probably supplied in your carb kit) can be installed to prevent you from tampering with it (because we know how irresistible that is).

1.96V is not remarkably high. The range is zero to 5.0V. The 1.96V would indicate somewhere around 40% throttle, but it's far too high for the ECM to be satisfied with it as an idle position.

 

Didn't get far today. As I said we wanted to confirm the scanner TPS voltage reading, by using the multimeter or my new "vintage" analog tach/dwell/voltage meter. Tried the multimeter, and just could not get good contact by back probiing. Tried the multi-meter probes, and pins. Nothing. Then I realized I had the multi-wire adapter out of my Thexton kit. Worked like a charm, and it confirmed the scanner reading. Read about 1.9 volts at idle. Also did live readings with the scanner. TPS voltage increased as throttle was opened up. Did not attempt WOT while driving--can do that by hand in garage.

So tomorrow is surgery (removal of TPS plug). Once we have that out we can do the adjustment.
I was hoping that once we do the TPS adjustment, using the multi-meter to get the spec idle voltage, we could then hook up the analog voltmeter to check for a good constant sweep up as the throttle is opened---but can't yet figure out how to hook the analog meter up. It has two leads with alligator clips on the end. One green lead, one black lead. Anybody know how to hook that up for TPS voltage check?

Also watched the mixture control numbers, and at idle it seemed to be right at 50%, and as we increased speed it would rise. Going about 30-40 mph, the mixture control read somewhere around 70-80. Can someone tell me whether mixture control % (dwell) should rise as throttle opens.

Finally, the scanner once again showed Lean on the Rich/Lean Flag reading. The book says when the state is lean, fuel is added to the system. What does all of this mean. I am guessing the carb is running lean and the ecm is telling it to add gas. Can someone tell me why it would be running lean, and is that consistent with the mixture control numbers mentioned above.

As always thank you for the help.

 

Set the TPS first, as that might be skewing the mixture tables in the ECM.

Regarding the connection of the voltmeter, clothing pins are pretty handy for that, and the type with the ball on the blunt end can be really handy. Clip your alligator leads to those after they are stuck into the backside of the TPS connector.

I'm going from memory, since they no longer let us handle sharp objects here on the inside...

 

The surgery was a success!!! The patient is resting comfortably---in the garage, and the doctor will now have a beer!!!
In other words, the offending plug has been removed, and we lowered the voltage. We thought we set it to the spec voltage of 0.48, but we did a scan after and got a reading of 0.54. Will drive it a bit, get a couple of more readings, do a live scan, and if continues to read a tad high, we can try and fine tune it a bit.
Car did seem to have a bit more power, and more responsiveness. Ran well. It was a GOOD DAY!.

Now we plan to finish checking the rest of the external carb adjustments, and hopefully get it really tuned in.

Big shout-out to Vader! Thanks so much for the help.

 

That's great news!...

 

The voltage was very likely 0.48V when you adjusted it. The battery was likely producing 12.6V or just a bit less at that time, just like it should. Once the engine starts and the alternator takes over to do its job, the system voltage can be 14.8V or more, and is usually more for a brief period right after startup until the regulator/battery/load stabilizes and the battery gets recharged a bit. Even though the 5V reference signal supply from the ECM is supposed to be regulated at 5.0V, the higher supply voltage can force a slightly higher output from many SS regulators. That's completely normal.

In other words, your adjustment is probably just fine and the ECM is seeing a more appropriate closed-throttle voltage when the ignition is turned on, which is most important. It's certainly way better than almost 2V. Enjoy that beverage.

 

Thanks for that Vader---makes total sense.