Been working on a 1990 Corvette for a few years now. You can check out the progress in my thread entitled "How not to flush engine oil." I ordered a tune from a company that has a fairly good reputation. The engine is lightly modified, ported heads, degreed cam, roller rockers, tpis miniram. I installed the chip at the same time I installed all these other parts and at first thought the injectors I chose were to big. So I replaced them with 22lb injectors and sent out for a retune. It still wouldn't run right. I came up with the idea to pull the chip out and put the factory one back in. Car started up, ran ok, and stayed running. I thought I had maybe got a bad set of injectors so I purchased another brand new set, installed them and reinstalled the tune. Cars not running at all. Took the tune out, car runs and idles. I need this car tuned because I am missing egr, air pump, cats, and have a lower temp thermostat. But I've never heard of a chip not working. I find it hard to believe a company that does this exclusively couldn't get it right 2 times. What are your thoughts?

Also I am located in the NY, NJ, PA Tri-state area. Who tunes these cars?

Dan

Dumb question - did you use the chip adapter and install the chip the correct orientation?

could just be a bad chip

can you send it back for another?

Can you plug an a scan program?

Ok,

Sorry for the delay in response. Just been really busy. So I called the company and they offered to send me out a new chip with the same info on it. So I installed the new chip and now the car runs, and idles but its still running rough and the check engine light is on. So the chip was definitely bad but the problem still isn't completely solved. So I ran the codes on my OBD1 scan tool I just got tonight and it came up with a Code 41 and 42

Code 41, Cylinder select error

Due to the same ecm being used for different engines, it is important that the proper prom is installed for the particular engine, a incorrect prom, not installed properly, or faulty. Another cause is the pins of the harness are not properly connected to the appropriate pins on the ecm, and/or the grounds could be open. For V8 applications, ecm pin D3 is grounded.


Code 42: Electronic Spark Control Issue

Now,

I am running a Camaro distributor with an external coil on this car so I am not sure whether or not that could be the cause of code 42 but after a little research I am thinking the ECU is not recognizing the "chip" they sent me??? What's the deal. I can't see why I am having so many problems here...

DG

You usually get a code 42 when the EST wire is disconnected. That will cause timing problems and could be related to your issue. I would check that circuit thoroughly, make sure the wire is not broken/burnt/grounded, etc.

What adapter are you using for the memcal? A moates? Did you check the orientation of the chip?

I should have mentioned above....

The code 42 always accompanies setting the timing since the est wire is disconnected. It could simply be related to that and nothing else.

The code 41 is likely from the previous bad prom.

I would reset both codes and run the car, then see if one comes back.