Very strange problems...Tune related?...Video inside

[1slow95]

It started out as a surging idle, and sometimes dying in parking lots and such. I tried to reset the idle, pulled the spout and unplugged the IAC, then set the idle to around 650rpms. I then disconnected the battery and let it sit overnight. When I started it up this morning it was acting very, very strange. It's sitting at idle, then it's like all power is shut off, then the engine revs up to 2k or so. It would keep doing that, sometimes going up to 2500rpms and hanging there for a few seconds. Here's the strange thing, I tried 3 of the tunes on my SCT chip and it did on 2 of them....I then switched it to the stock tune and it runs almost perfect. Is it possible my chip went bad?

Here's a compilation video of every time it did it that I could catch on tape. It's compressed down to 1.51mb so the quality isn't great.

Keep in mind I never touch the throttle in this video.
Right click, save as

I know the idle is high, I tried to fix it but it's a problem with the tune.

 

[1994Vib.RedGT]

my car does this too, and that was even when it was mostly stock, i would be cuorious to see what it is too.

 

[1slow95]

I just pulled the codes, here's what I got:

511 - EEC processor ROM test failed
334 - EGR closed voltage higher than expected
565 - Canister purge circuit failure

All three showed up twice, and the 334 code showed 4 times total.

Is it possible that's just the computer re-learning? Because this just started after I reset the computer...

 

[1slow95]

Ok, I think the problem was a poor connection where my chip plugs into the ECU. I was letting the car run and it was doing it's crazy thing, then it died, the fan shut off(it's been on constantly since the chip install), and the injectors and fuel pump stayed on. So I removed the chip and cleaned up the pins on the ECU and reinstalled the chip. It ran fine for about 15-20 minutes before I shut it off. I really hope that fixes it, but I won't know for sure for week or so because Im sending my chip back to my tuner to fix a small issue Im having with the idle speed.

 

[SeventyMach1]

Hope that was it man. Simple fixes are always nice.

 

[1slow95]

Just a follow up, Im almost 100% positive it was just a poor connection to the chip. I got my chip reinstalled tonight and it hasn't done that again since I cleaned the connections.

 

[1slow95]

Stupid ****ing piece of **** car!

Ok, so it ran great with the computer hanging out of the kick panel. Today I put the computer back in the kick panel and it's doing the same **** again! What the hell could be causing this??? The car runs absolutely perfect on the stock tune, but it flips out whenever I switch to any of the custom tunes

 

[HISSIN50]

Is it changing tunes, or simply installing the puter back in the kick panel recess? I'd check pin connections and try to unstress the wiring harness near the computer if it's simply from installing the puter in its home.

Good luck Mike.

 

[1slow95]

I had the puter laying on the floor from where I sent my chip out to have a few adjustments made. It ran fine when I got my chip back and reinstalled it, with the puter still on the floor. So today I disconnected the puter and put some tape over the chip, put it back in the kick panel and reconnected everything. That's the only thing I did.

I'll pull it back out tomorrow and see if that helps...


What about this...I just remembered I ran the wire for my chip(to change tunes) with the wires from my ignition box that go to the coil...Could I be getting interference from those wires???

 

[94greenhunter]

have you had the puter checked out there might be a seris off in the computer or you just might just need a new chip

 

[MysticKeith50]

Low...I can tell you I had the same exact...exact thing happen to me. Car was doing the same thing..yadda yadda yadda, found out it was a rotten connection, sanded the connection a bit, rubbed with alcohol....perfect...perfect for 1 week...until I put the computer back in the kick panel. I had to take it back out and really secure it with tape, and make sure none of the wires were stressed/unhooked. I re installed it and it has been great for like 4 months(knock on wood).

 

[Methodical]

My take on this is the Chip's connection to the computer. Tape it to the computer but don't use Duct tape or Masking Tape - the heat will weaken their bond. You should use something like a Scotch Packing Tape (clear). This is what I used with my TwEECer. Also before taping take some alcohol and clean the computer's case (don's soak it though just wipe it). Be careful when you reinstall the computer and don't force anything. The chip on mine does not allow the reuse of the white bracket but I have it sitting snug in there.

 

[BlownFiveLiter]

If it does turn out to just be corrosion on the contacts, put a dab of dielectric grease on there when you reinstall the chip. It should prevent future corrosion.

 

[1slow95]

I took the chip out tonight and cleaned the contacts with rubbing alcohol. Reinstalled the puter back in the kick panel and took it for a short test drive....So far so good....I just hope it stays good this time.