The pre 89 MAF codes must be some sort of GM joke.

After too much time and frustration (How I hate EPROM burners, let me count the ways) I finally have a slightly modified ARAP code in my dads car, which has a built up 350 TPI and a relatively large cam. I had it running pretty good on an 88 code at WOT, but part throttle was a *little* off and idle... sucked... BADLY. So I put the ARAP chip in after having the battery disconnected, and fired the car up when it was cold. This usually resulted in: 1100 800 1100 800 1100 800 1500 800 1500 800 1100 800 for about 3 minutes as the computer tried to learn its way into a decent idle. This wasnt the case this time. It fired right up, didnt flare up to 2600rpm after I started it, the idle dropped down into a nice steady rhythm at 1000. Put it in gear, 700 rock solid. Thats much more like it. It runs nice, feels better SOTP, and Im sure it will keep me happy from now on. I dont know what you guys are waiting for (or what the heck I was waiting for or messing with the early stuff for), ditch the cold start junk and run the arap.

[This message has been edited by madmax (edited March 10, 2001).]

 

Madmax,
About the ARAP bin. I understand its a hopped up program. But isn't it for an auto tranny? I would be running it if it weren't for that. Oh yea, i'm running the APYP(stock 89vette 6speed chip with vats disabled). I haven't done any tuning but that chip alone has gotten my idel right at 700rpms. Still needs some work but much better than a 305tpi chip with all of the mods listed!
Would the ARAP chip work alright for my setup? Could i send you an image of the bin i have so you could maybe compare for me to see how radically different they may be?
Drop me an email madmax.

Thanks,

Brendan

------------------
1987 IROC-Z L98,SuperRam,EB 6085's,LPE 219/219 Roller, Crane 1.6RR, EB TPI Base, 58mm TB, ADS 24#, AFPR, K&N, EB TES, Catco Cat, 3" Borla Cat-Back, Accel cap,rotor,distro/other crap, MSD 6AL, MSD Blaster 3, Aluminum DS, 94 Disk Rear, Adjustable Valve, Precision 3.73 Gears, Sub-Frame Connectors, Hotchkis Lower Control Arms, KYB Shocks/Struts, Suspension Techniques Lowering Springs, Polyurethan Bushings all over the place, Moog Upper/Lower Ball joints and Tie Rods ends/Idler Arm,

To see the ROC, Check out the webpage Here

 

Yea, I picked it up from the gmecm site. Theres a spot you can set it for a manual trans, although I had seen some earlier bins where the timing curves were different from the auto to manual bins. Email coming.

 

I am running the code from the ARAP bin now. I used many of the values and tables from my 88 bins. Should I be using the MAF tables from the ARAP bin? I plugged in the values from my ADS aftermarket chip.

On the cold start junk, I was thinking of pulling the 3amp fuse that runs this circuit. Not only is there the cold start injector, but also the cold start temp switch, that runs every time you crank the motor. If you just pull the fuse, then none of this circuit will suck any power from the battery during startup, especially since it is not being used. I suppose you could just pull the 2 connectors also, to do the same thing. Eventually I will spring for the cold start plug kit. Does this fuse power any other circuits in the car? I couldn't find any in my service manual.

------------------
Best ET 14.413 @95.57 without
pulling valve covers or manifolds.
Also with stock 2.77 rear end!!!

 

Yep, I'd use the MAF tables from the ARAP bin. Nope, the 3-amp fuse only controls the cold-start injector. That's how I first disabled mine when I switched to the '89 code, then I removed the injector and blocked off the fuel rail and the hole in the runner where the injector was.

------------------
Greg Westphal
'87 IROC 305TPI/A4

 

Greg, so you're saying on an 86-88 car, its possible to use the ARAP 89 code just by removing the fuse for the 9th injector? It can physically stay there, without putting in a block-off kit? Thanks.

------------------
West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

Yep, that's what I think he is saying. Tonight I used a test light on the cold-start injector, and watched it go on when I cranked the motor. It was on for at least 2 sec, since it was about 35degF in my garage. Then I pulled the fuse, and no test light at startup. I then plugged the connector back into the cold-start injector. Now no one will ever know that it is not being used.

Thanks for the tip on the MAF tables. I will print them out from the ARAP bin and compare to the ones that I am using.

 

Yea, the cold start is completely separate from the ecm. It has a switch at the front of the manifold that controls it. I just disconnected the injector for now.

 

Great, so I dont have to buy the 32 or 32B ECM files from Tunercat, just the 6E.

 

The ARAP was a magazine car calibration. It was used in all the test cars for MY89. It was the best of the best that would perform and met EPA approval. Folks really don't really appreciate the time GM puts into a car for driviability, and EPA approval.

 

So the ARAP file is not a stock 350 auto bin. If not what was it? magazine car calibration from GM? sounds weird..... Are the spark maps good for a aluminum headed motor?

------------------
355 10:1 , AFR 190 heads, LT4 HOT cam w/ 1.6 roller rockers, complete Superram intake, 58mm BBK TB, 24# injectors, screens out of MAF, MAT relocated, March underdrive pulleys, Streetdampner, Crane HI-6 ignition, 160 thermostat, K&Ns, TES headers(Jet hot coated), Mufflex 4' cat back, B&M shift Kit, 2500 converter, and 3.27s.

 

Soooooo, how exactly did this ARAP .bin become "publicly" available?????

------------------
-Greg

'85 Trans Am - WS6,TPI:
Original owner, original paint/engine/interior, plus the usual bolt-ons

 

Youre right, I dont. You know everything about someone from a small quote dont ya, you genius you.

Greg, I think that someone from the diy-efi knew somebody and got their fingers on it.

 

You'd be amazed who lurks there......

***** several anwers
The AL heads make for quite a different animal, for timing (when using non oem cams). Also, can run alot less timing at WOT, and if you smooth out the chambers really make a difference.

If I had to cal a man trannied 89 I'd use the ARAP, and then run a fill compare for all the misc stuff like IAC settings. Then work off of that.

The magazine cars are almost pre production so there are some months between evaluation and release to the production line. Once the ARAP was found to work so well, then it went into alot of production cars.

What GM has to fight in the EPA arena is no minor thing. If you look at some of the stuff, you'd swear someone was drunk, until you look at the options and then some of it is brillant.

 

What would happen if I were to try to swap in a TPI system and I don't have every wire from the car?? I have alot of the harness for under the dash, the complete harness that goes from the computer to the motor and little else. If the 3 amp fuse you talk about above is part of the fuse box, then it looks like I'm in trouble. Don't get me wrong, I have the fuse box but I didn't plan on actually using it. Also all of the lettering has been rubbed off.
So my question is this, since I took the TPI off of an '86, what trouble can you forsee?? Since I don't plan on using the 9th injector, would I even have to worry about it, or is there other stuff that is TPI specific about the fuse box and harnes.

Also, what cold start sensor are you talking about, is it the one with the 2 wire weatherpack connector that is used for alot of the temperature sensors or is it the one with the Bosch style fuel injector connector. As far as the cold start plug kit goes, can't you just use a freeze plu of the right size?

------------------
'86 TA, T-tops, T-5, 3.73, 4 wheel disks 350, compucam 2040, performer intake,SLP Headers, 3" race magnum muffler, 1.6 Comp rockers, Ripper shifter, perf. friction pads, Hypertech ignition, Earls brake hoses, Hotchkis springs, Tokico Illumina 5 adjustable shocks and struts, Lakewood panhard and trailing arms
14.73 @ 95... traction still a problem

 

The cold start switch is the one with the "injector" style connector on it at the front of your intake manifold. Just disconnecting that works fine, and is how I have been running since I put the ARAP in.

------------------
Mike Metzler (Desert86Roc)[*] Check Out:SpeedWorldMotorplex.com[*] Check Out:Chevrolet F-Body Online Part & Illustration Manual[*] My 86 IROC 305 TPI Page (406 build in progress)

ET's @ 1250 ft[*] 14.28 @ 95.461 mph (uncorrected, NOS, no headers)[*] 15.362 @ 88.238 mph (uncorrected, headers, no NOS)
<><

 

besides the 9th injector what major differences(specifically between that and the stock 87350TPI calibration?..

Daz
87 IROC stock chip

 

Hmm, was a little over 2 years ago. A friend of mine let me in on what the deal was with it. It's been publicly available since late 88, just no one had ID'd what it was.

 

Where exactly is the 3 amp fuse located? I looked in the fuse panel and owners manual but couldn't find a location for a 3 amp fuse. I ended up just pulling the injector plug off for now.

My experience with the ARAP consisted of harder starting. For some reason the car cranked over 4~5 seconds before starting or me having to re-try starting. When I swapped other bins onto my prom they started right away. I was too lazy to try and re-adjust my IAB to see if that would help. But it was strange that only the ARAP had a problem. But the spark advance and TCC lock/unlock made the car feel faster. The high spark advance allowed better light throttle acceleration.


James

------------------
1985 Z-28 305 TPI
165 ECM,STB,SFC,GW "wonderbar"

 

I'm having the same problem. The car doesn't start nearly as well. Sometimes it does, but usually it takes two attempts or one very long attempt. I haven't figured out what to change to improve its behavior yet, though. I have bummped the IAC park counts, then the cranking pulse widths. Neither has helped much. I would sure like some guidance on where to go to fix this problem.



------------------
'87 IROC 5.7l TPI - original owner!

 

My experience with the ARAP consisted of harder starting. For some reason the car cranked over 4~5 seconds before starting or me having to re-try starting. When I swapped other bins onto my prom they started right away. But it was strange that only the ARAP had a problem.


Yea, I've noticed this too. After rechecking the bins I sure can't seem to find where it would be coming from. Anybody with idea's? Grumpy? Just a BTW-on the more agressive spark curve on the ARAP and alum. heads. I compared a stock 88 vette bin (alum heads) and it's spark curve is identical to the ARAP, but a stock 89 vette bin has less lower load and mid rpm timing; but the same at WOT-go figure???



------------------
86 406

 

I am having problems getting the ARAP bin to work in my 165ecm. Currently I am using a 32B code which works relatively fine, however, I want to switch over to the 6E ARAP code.

My problem is: the car starts up right away, runs like a champ at 1500 rpm with a solid, bright yellow, Check Engine Light! I am unable to acquire data from the Diacom with this chip. Also, both fans come on as soon as the ingnition is on. Does anyone have any thoughts on this?

------------------
1987 383 cu.in. IROC-Z: TPIS MiniRamIII / GM FastBurn heads/ 10.6:1 compression
Comp cams custom grind: Dur'n 224/236 Lift .536/.555
Strange 12Bolt Diff./ Neil's Home-Built BulletProof 700R4+Vigilante 2800 stall converter
MSD Billet Distributor, Dig 6+, & Blaster coil
Hooker Supercomp Long tube headers

 

I can't help you with the Check Engine light, but I can with the fan(s).

Only one fan is computer controlled. It's the driver's side one. The other is activated by a temperature switch in the pass side head. Are you sure that both fans are coming on?

The ARAP code is '89 based. Apparently in that year GM changed the A/C pressure switch from normally closed to normally open. Because your switch is normally closed, the prom is telling the ECM that the A/C pressure has built up requiring the fan. There is a switch (with TunerCat, at least) you must change to fix this. "Un-X" the Normally Open fan request switch.



------------------
'87 IROC 5.7l TPI - original owner!

 

PJ,

Thanks, I will give that a try and I'll keep you posted.

 

Neil, with an SES light on and both fans running, that means your car is in limp-home mode. You have a bad chip. Try reburning your chip and try it again. It probably didnt get a full burn the first time. Make sure you verify the chip a couple times in your prom burning program after you burn it.

------------------
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.23 @ 107.62 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

drive it, I looked at my arap .bin and noticed that the start up spark advance vs. coolant temp were all set at 0. This looked pretty strange to me just because they were all the same values, maybe it will have something to do with the hard starting!!

------------------
'86 TA, T-tops, T-5, 3.73, 4 wheel disks 350, compucam 2040, performer intake,SLP Headers, 3" race magnum muffler, 1.6 Comp rockers, Ripper shifter, perf. friction pads, Hypertech ignition, Earls brake hoses, Hotchkis springs, Tokico Illumina 5 adjustable shocks and struts, Lakewood panhard and trailing arms
14.73 @ 95... traction still a problem

 

I've been using tunercat which doesn't have that table, but I saw it in winbin. Looks like it might be worth a try, thanks. Also I saw in tunercat the "stall saver". I was thinking of disabling that also. Anyone else out there already tried either one? Did it work?



------------------
86 406

 

Kevin 91z,

Thanks for your reply, because you pretty much figured out the problem--The memcal was bad. I put the same eprom (w/ the ARAP bin) in another memcal and the car fired right up with no SES light. Thanks again!

------------------
1987 383 cu.in. IROC-Z: TPIS MiniRamIII / GM FastBurn heads/ 10.6:1 compression
Comp cams custom grind: Dur'n 224/236 Lift .536/.555
Strange 12Bolt Diff./ Neil's Home-Built BulletProof 700R4+Vigilante 2800 stall converter
MSD Billet Distributor, Dig 6+, & Blaster coil
Hooker Supercomp Long tube headers

 

First time chip burner. Just got my PP yesterday,and burned a couple of chips lastnight. I used a modified arap .bin. Burned on image on a 27c128 and one on a 27c256. On the 128 the car started ok but ran real rough compared to my hypertech/3 chip. On the 256 chip solid ses light. I burned the chip with the code on the lower part just like my hypertech chip was burned. I erased the chip and burned it with the hyper code on it,haven't tried it yet. Any ideas why the two chips behaved differantly?


------------------
87 GTA 355/700r4
ported&polished 083 heads
xe268h comp cam
1 5/8 blackjack alumicote
homebuilt y pipe,pasesetter 3in mandrel cat back.
ported/manifold,upper plentum, tpis maf.
airfoil, 24# svo injectors, hypertech stage 3 chip, underdrive pulleys, erson roller rockers, chromemolley pushrods,2100 stall, shiftkit, 373 10 bolt.

 

I'm not sure about your car but I know with mine I have to burn to the upper half of a 256, anf fill the lower half with FF's. I'm pretty sure that's what everyone else has been doing as well, hypertech maybe set it up different so that it would work on the lower half, try it on the upper. There has been alot of talk about how to do this in other posts, do a search for 29c256.

 

PJ,

I am researching how to configure the Bin parameters as I will soon be burning a new EPROM. In
reference to the thread you posted back on 6-13-2001 you stated fan #1 is controlled by the ECM
and fan #2 is controlled by the stock 235 degree temperature switch. I agree. While reviewing
the definition values for fan control in the stock ABWT bin file there are ECM temperature
control values for both fans. This is confusing since fan #2 is controlled independently of
the ECM. Below are the ECM set points as in the EPROM.

Fan 1 ON (AC On) 226.41 deg.
Fan 1 OFF(AC On) 220.81 deg.

Fan 2 ON (AC Off) 226.41 deg.
Fan 2 OFF(AC Off) 220.81 deg.

So as I understand say the engine is below 226.41 degrees but the AC is turned on. When the head pressure gets to a certain PSI this will also turn on Fan 1. Or the AC on and head pressure is low but the engine is above 226.41 degrees, Fan #1 will turn on. Or the AC is off and the engine is above 226.41 degrees, then Fan #2 turns on.

My question is why are there set points for Fan #2 in the EPROM? Is it possible that either the ECM OR fan switch can control fan #2? Sort of a backup safety to force the second fan on in case the ECM should fail to detect the temperature. If this is true then the ECM would turn on Fan #2 at 226.41 deg. when the AC is off, or if the temperature sensor for both the gauge and ECM should fail then the 235 degree switch would switch to ground forcing the relay to switch on and turning on fan #2.

Does this sound correct to you?

Vance

 

In reference to PJ Moran's post on 6-13-2001 he said stated for the 87 IROC/GTA the AC pressure switch is Normally Closed.

In 89 GM changed the AC pressure switch to Normally Open.

In the stock ABWT bin. file...

"A/C Pressure Switch Specification Byte" flag option is hex "b3".

In the 89 ARAP.bin file the "A/C Pressure Switch Specification Byte" flag option is also set
to hex. "b3". Wouldn't the software require a different hex code if the switches were reveresed as started in 1989?

Vance