I'm not sure where to post this..so if this needs to be moved, please do so.

I've got a random question..my car wouldnt start up after being drove for about an hour a few weeks ago. I waited a bit and it started up just fine. As I was going home, the SES light came on but went off after a few minutes. I checked it when i got home and there were 2 codes..a code 43 and 54. I think I have the code 43 fixed, but not sure because I didn't clear the code after it first came up. A week before it died the last time I replaced the starter and coil because it kept having the starting up problem. Could the fact that I have a 350 in my 89 rs and still the factory 305 chip in cause the SES codes? I'm trying to word all this right..I'm so pissed at my car right now things may come out wrong! haha. Anyway, thanks for reading. Any ideas would help!!

James

 

a 305 computer chip could definately be part of the problem. Need more info on the 350 (tpi or carb, cold start injector, what year for the engine? etc). The '89 chips (or memcals) were different from all other years, and there were differences in the memcals to compensate for the different specs depending on whether or not it was 305 or 350, auto or manual, etc.

As far as the car not starting after you drive it, that's called heat-soak or something, and it's probably due to excessive heat being absorbed into the starter (from the exhaust manifold / header on that side). Once this heat dissipates, your starter is able to crank your engine. Common on these cars. If you still have the problem, you can get a heat-shield installed for the starter to block the heat from being absorbed. Good luck

 

ok, lets see...the 350 is TBI off the 89 RS 305. The 350 is a rebuilt 88 i believe...not sure tho cuz I got it from Advance Auto Parts. Its an auto..I replaced the starter, 350 knock sen., tons of things so far tryin to figure out whats goin on. Now I'm jobless and out of money and I cant make a chip or really do anything for that matter.

 

ok, well I'd say since there were no TBI350s in thirdgens, you will have to get a different chip for it to work properly, or perhaps you'd be able to find a computer (or memcal) from an '88 truck that had a tbi350 that would work for your vehicle (or go buy one from GM). I'm not sure if they'd be interchangable, maybe a TBI guy could help out here? In any case, you'll need some cash to make any attempt to fix this problem, and if the Advance 350 you bought has different specs than what an '88 tbi350 has, then you'd probably be in the same boat, or possibly a more leaky one heh

jc265, you might consider 1) searching the TBI thread for answers, and 2) reposting your question in the TBI thread. TBI guys any help?

 

Just went through this with a '91 RS I bought...

But, a little background...it was converted to an LO5 (350) crate motor a few years back, installed with 6?# injectors for the 350, 350 KS , but unsure if the ESC was changed wither...and ran on the 305 chip without SES light...previous owner did have the fuel regulator made adjustable and that did cause some issues with AF...

But, main thing is no SES light with the LO3 chip.

Next, the truck chip won't work, it's a different ECM, for a 350 swap, start with an 89-90 Caprice chip w/LO5. I forget the chipcode, but can dig it up tomorrow.

 

I ran my 89 like this for a while, L98 long block w/ factory tbi induction. It constantly threw codes, and the rpm's would go up and down at idle. I swapped the injectors for a pair of L05 ones, that took care of the hunting idle ,and put in a chip from a caprice police car. That took care of most of the other problems, but would still occasionally throw a code 33 (map sensor).

 

Do you have 350 injectors, knock sensor, and custom chip work? If you have a stock LO5 you can get away with the LO5 caprice chip as others mentioned. If the engine has any work done to it the only way to make it run as it should it with chip work. The stock PROM is 100% un-fit for the job and will make your car run slower than when it had the LO3.