JPS

So, long story short, I have a fresh, down to the crank, rebuild as a 3.8. 1000 miles on it now. New chip from Wong, so quality stuff. Gave the specs of the build and all that.

First track day, as I got to the cool down lap, the CEL would come on for a bit and then go off. Stayed off until next session cool down. And with the chip in, top speed and lap times were significantly down vs. 3.6 and old chip.

Now, I'm getting the codes from the shop, but this seems to be a bit of a head scratcher.

Has anyone encountered this before?

IainM

Paddy

JPS, it could be hundreds of items. Need WAY more info here.

gt-2

I have a duplicate unit....95 3.6 rebuilt to 3.8 and a wong chip but my complaint is I have a massive flat spot at 4k rpm until about 5k rpm and it takes off like a rocket again. I know it probably has to do with limitations with stock intake but its bad and I get no help from Wong when I called to see if chip could be culprit. Don't want too highjack thread but anyone know if getting the crossover valve to open earlier helps and how you would do that? I'll check to see if any codes as my CEL light bulb is shot.

JPS

I know I need the codes to help more. But just seeking parallel. Has anyone gotten CEL when hot and what was it?

cgfen

Is the chip vendor not willing to help with this?
if not, that's a big miss on their part.
They would seem to be the go to resource.

JPS

Yes they are sort of. But hasn't encountered it before. Hence me reaching out here.

Lorenfb

It's possible the ignition timing was "pushed" too much and the knock control system is retarding the timing over what the stock Bosch/Porsche chip provided.
Any "real tuning" needs to be done on a chassis dyno. Read here; http://forums.rennlist.com/rennforum...-the-myth.html

Paddy

Injector duty cycle, bad timing, knock sensors, maybe the EPROM chip was burned with the wrong camshaft profiles, etc.

I wouldn't track or drive that expensive motor build unless I was 1000% sure the ECU was right. It's an ODB1 car, right? Why not do a standalone ECU and have it tuned properly? Geoffrey Ring is in New York at Racetek engineering and can get you sorted.

-Paddy

Yep, Lorenfb posted right before I did. I completely agree.

Steve Weiner-Rennsport Systems

Jos,

Don't get the cart hitched in front of the horse, here.

Read the code(s) that have triggered the CEL FIRST to start the troubleshooting process!!

Lorenfb

Easiest step is to put the stock chip back in and do an extensive evaluation, i.e. verify it's a chip problem only.

HDA

#11 posts and still no codes!?

Paddy

JPS

No codes recorded. And it is at the shop and at the mercy of them getting me the intel.

Doesn't come on with my 3.6 chip. But there might be a problem with the igniter as it doesn't seem both banks are active. So stay tuned. No pun intended.

jstyer

Doesn't come on with stock chip? That seems surprising to me.

My car with rs valves and dc-10 cam runs on either my stock or my wong chip.