I'm having a serious problem after attempting some minor changes to my chip. Car is a 1991 TPI w/ a 355, 5 speed. To break in this new motor, I used a S_AUJP bin graciously sent by a fellow member which was tweaked for his car (which lined up pretty close to mine). The car generally runs well, the only issues are a very long cold start and the occasional stall when pressing the clutch or during long coasts in neutral.

After doing some research I felt that the throttle follower data might be the culprit. So I changed some of the IAC stuff in the S_AUJP to AXXD values to see if that made any difference. The problem now is that the car will start but die immediately. The rev's jump all over the place and the motor dies in a few seconds. Even the application of throttle only slightly delays this problem.

Thinking it was my reckless changes to the bin, I reverted back to the old program which, as previously noted, was totally drivable. Exact same problem. I'm using a BURN 1 programmer and a G1 adapter with a ZIF socket. I've had no problems before, I've even burnt new chips on the roadside with zero issues so this is completely new to me.

There are no error codes stored, no vacuum leaks or anything like that. My complete guess is that something is wrong with the ECU or the chip is somehow physically damaged. Has anyone had this problem?

Additionally, if anyone has some direct comments regarding the throttle follower and what could be causing the long cold start, I'd love to hear it. I plan on diving into as many tech articles as I can tonight to start figuring this out, but the car has to run first!

 

I'm not familiar with your hardware, but I guess the first thing I'd want to do is try to verify that the chip's program matches what you programmed.
My programmer verifies chips at low and high voltage (on the fringes of what's legal for a 5V chip), but even so, I've still sometimes had chips that triggered a "PROM error" in the car. In that state the behavior became erratic.

If you don't have any other chips, I'd probably get some. I try to always keep a known good chip alive at all times, just in case the new burn doesn't go well.

Long cold start might be caused by something in the tune causing a bad mixture while cranking. But I can't suggest anything more specific, sorry.

 

key on engine off should be a blink of CE/SES light and then steady on. If that is good the .bin is properly loaded. If rapid blink of CE then .bin is an issue. Are you properly stacking the .bin?

 

Try eliminating the G1 adapter and the ZIF socket as an issue.

 

Thanks for the help guys,

SES at key on checks out fine. I tried disconnecting the battery, same problems. In terms of stacking, I'm not entirely sure what that means. If that has something to do with the addressing, I double checked that and it appears fine. Tonight I will try without the adapter and ZIF. After that, I guess I'll try new chips. I should have more anyway, it's just unfortunate one has to order them online. It worked flawlessly last summer, maybe the chip just went on me. The only difference is last year I used tunerpro 5 instead of 4, but I even tried buring the PROM without opening it in tunerpro, just buffered the original file in Flash&Burn and programmed the chip.

 

I had this same problem. After messing with the tps, iac and other pointless items i realized the dizzy had moved just slightly.

 

Interested in your results

 

I never had to stack but think of it as the size of your chip and the size of the .bin. I blieve it has to do with the them matching up. Do a search. It is a common issue.

 

I have an update for those interested. It turns out that the chip was not the problem, but the ignition module. I since replaced my cheap eBay distributor with a full unit from Accel, module included. The car now starts and runs with the same chip I had been using before.

It took me awhile to come back to this issue as I started doing a full front end steering/suspension retool since the car wasn't drive-able at the time anyway. Like most of my projects, this took much longer than expected and last night I finally installed the new distributor and fired it up.

Certain problems are still there, and I'm not sure if the stalling will persist. I drove it for a few miles and no stalls occurred, but the idle still hunts a little bit. Looking back, it definitely makes sense it was the module (or something distributor related). The fact that it got worse when hot, started stalling all the time and then finally crapped out completely all indicate a heat damaged module, which is apparently a very common problem with these cars. I had assumed it was the chip since I had just changed it - I now realize this was a bad assumptions!

 

AUJP is an automatic bin, and I believe S_AUJP is default set to automatic.

What you describe sounds like what occurs when using an automatic bin with a manual transmission.

Check this setting(s) and change accordingly. There should be a flag setting for it, but I'm not sure of other changes that need to be made to change over to manual trans.

 

The person I received the bin from had been using it successfully with a stick so I believe it should be OK in that regard.

 

Have you checked the bin to be sure?

 

As Six Shooter said, AUJP and S_AUJP are set for automatics. This can be verified by looking at the Calibration value (under "Flags" in TPro) in bit 2 of byte (Switch) 18 (0x8018). Automatic = 0 (Not set); Manual = 1 (set). But in addition to this bit, there is also a variable in the AUJP code at 0x8671 that defines the trans type, but don't believe it is availabe for editing through the downloadable XDF files (0= Auto; <> 0= Manual). Looking at teh code, this appears to be an inportant variable in controlling IAC position when RPM is within 1587 of Desired Idle RPM (the normal case) and the car is Moving. You can change this bit with a hex editor or create an entry in the XDF so it can be edited.

Regarding a bin working in another car -- there are so many variables it's hard to say that what works in one will work in another. If that were so, there would likely not be so many posts here with the variety of issues seen day to day.

Try changing the bits and see what happens. Only takes a few seconds. If that's not it, change em back.