gluck86

Hi all, new here and this is my first post. I bought an 86 IROC z with everything original minus a hypertech chip, but I'm having trouble with the cold start. I can spray starter fluid in the throttle body and it will start, run, and once the engine's warm it will crank just fine. I bought but haven't installed the cold start relay but found that GM has discontinued the cold start valve/injector and so has every other parts store. So if the cold start switch doesn't fix it, is it true I can buy a block off kit and use say an 89 IROC hypertech chip and be ok? This is really eating me because I really want to drive it and enjoy it...

vetteoz

iTrader: (13)

If the injector is not leaking you don't even need the kit.
Just disconnect wires at CSI switch and injector ; it will serve to block the hole.

Can use any '89 chip that is correct for your combo ;
'89 TPI has the cold start built in by using the 8 injectors

Could be a wiring problem
Check that you have 12V going to the switch when cranking ( only ) and 12V from switch to cold start injector when cranking.

hellz_wings

iTrader: (2)

I blocked it out with a TPIS kit just because I wanted to remove any possibility that fuel would flow through that injector by accident or something. I also got a 1989 chip from TPIParts.net... The chip worked great! But now I do my own tuning ..

gluck86

Thanks you both provided good information. I'm confident I'll fix it now.

gluck86

Ok, I'm still having issues with this. I bought a PROM adapter from tpiparts that is supposed to disable the cold start but I still can't seem to get it started. I've replaced almost every part related to fuel/air on the engine and even the fuel tank (not to mention the actual fuel tank). It will only start if we use starter fluid when the engine is cold. After warming up it can be cranked just fine running and idling. What could possibly be keeping me from starting the vehicle when it's cold even after disabling the cold start? tpiparts states this about the cold start injector in case this helps:

Cold Start Injector:
GM used a cold start injector (also known as 9th injector) to provide extra fuel on cold starts on 85-88 models. In 1989, GM setup the PROM to add the extra fuel needed for cold starts, and eliminated the cold start injector. Eliminating the cold start injector is probably one of the most common changes needed on 86-89 proms. If you wish to have the cold start injector disabled, we will setup your prom with the 1989 code, and make any needed changes on top of that. You will need to either A) disconnect the electrical connector to the cold start injector and leave everything in place, or B) physically remove the cold start injector from the runner and plug the runner hole with a cover plate. If you go with this method you will also need to plug the hole at the back of the fuel rail.

hellz_wings

iTrader: (2)

That's odd because even when I had the chip with the 89 code (6E code) I still had the 9th injector plugged in and it started pretty good.. I just blocked it off to finish the job and also cuz I heard that fuel can leak from that 9th injector which is bad.

gluck86

I admit I still have mine plugged in too. I was going to try unplugging it tomorrow but now that I read your post, I'm not too confident that it will make a difference...

kevinc

Sounds like your fuel pump relay is dead.

When that happens, your pump only gets 12VDC when the oil pressure switch closes. This takes a lot of cranking on a cold engine.

gluck86

Well in case anyone seems to have a similar problem, I did get it started. If you want to buy the TPIPARTS reprogramming chip they can program your stock chip with the 89 code and its much cheaper than buying an 89 PROM. The problem I had with not getting it started after using the new program was... uh... the battery voltage being too low. I noticed today (I guess I had been trying to crank it so many times without charging the battery) and charged the battery up; it worked after that.

hellz_wings

iTrader: (2)

lol it's more often than not something small and silly! Glad you got it started. How is the engine starting now?

gluck86

starts fine now. But only time will tell. I'm putting a rebuilt 700r4 in it now and am selling the turbo 350 that was in it to the shop. I bought the car last july and it had problem after problem with the tpi setup and now the nightmare is over and it drives. I bought it with a carb setup though it is an original tpi but the owner couldn't get it to run which is why he swapped for the carb. But today I finally put all the pieces of the puzzle together and all the origiinal parts are back in it (minus the PROM). I plan on restoring the interior and exterior next. She's already pretty in my eyes but I'd say another 5k into the interior/exterior touch ups will get it near show room quality.