I can't believe how useful this site has been. Can't seem to stop reading.

Searched, but, nothing is even close too what I have done.

I have a 1986 IROC-Z. All parts are from the factory. But, from several different cars. Problem is, I'm not sure what to do next.

I have in the car now:

A rebuilt 1995 four bolt/roller cam 5.7L short block .030 over.
1986 5.0L injectors/fuel regulator.
1990 5.7L heads from a Camaro.
1990 5.7L cam from a Camaro.
1990 5.7L Lower TPI Intake.
1986 runners and plenum from 5.0L
1986 computer 5.0L
? year of car 3.73 rear end. Guessing is was pre 87.
700R4
1990 One belt drive
1986 Distributor 5.0L with correct gear
1986 Throttle body
Modified MAF
All sensors are 5.0L
I purchased all parts except slave cylinder and cross member too put a T5 in the car. But, now, leaving the 700. Console, pedals, trans, starter, flywheels (nodular and non), pressure plates x2, clutch.

I do realize that some of this may need changing. That's my question. Which computer and prom/eprom?

I do have 5.7L injectors, but, don't want to put them in without having them cleaned or checked.

Side note: None of the cars could have been put back on the street, without tooooo much work.

Thanks.

 

The SNAP ON scanner shows a fan request all the time. Cold and hot. But, the fan will not come on.

I believe the computer is not grounding the circuit. Is it bad? None of the a/c is hooked up. New coolant temp. If so, which computer should I get?

I can make relay turn the fan on, so, it does work. Thanks

 

To diagnose the fan control, you need to test for ground at the green/white wire to the main fan relay. With the AC off the car, the inputs to the ECM may have been altered somewhere. The same fan that the ECM controls is also the AC condenser fan, on dual fan setups. On the single fan system, wiring and controls are the same as for the main fan in the dual fan system.

If there is no ground at the grn/wht wire, check again at the ECM, pin C2 of connector C1. If data stream shows the fan commanded on and there is no ground on circuit 335, the ECM is probably faulty. Verify all powers and grounds to the ECM before replacing it. Check all grounds circuits at the rear of both cylinder heads.

Fan commanded on at all times is probably due to the old AC wiring. The AC high pressure switch was the ECM's AC condenser fan request input.

The 5.0 injectors are too small for the 350, regardless of ECM tune. The only way they will work is with increased fuel pressure to compensate for the smaller nozzles. Otherwise, there is nothing in your parts list that would call for any kind of custom tune or unusual EPROM.

The easiest ECM to install will be the 86 as it will match up to your vehicle's existing harness and configuration. The 87 or 88 would probably be fine too. The tuning and configuration didn't really change that much over those years. The 87 had dual fans but the secondary(heavy duty) fan wasn't controlled by the ECM and the ECM wouldn't know the difference. The later ECMs were speed density and unless you are ready to completely swap ECM harnesses, you don't want to go there. Others may have different input but there is my .02

 

So you basically have a 350 tpi with 305 injectors. That sums it up . Your fine just make sure ur using 350 knock sensor, esc module and prom chip.

 

All factory parts, except headers with o2 on drivers side.

I don't have a knock hooked up right now. Can't see how the esc knows it isn't.... is there?

Just a short history of car. Bad storm that came GA. And giant limb decided to land inside one of my t tops. About a 8 inch around limb. Bad day...

Removed engine, stripped doors and complete front end and painted body. Now, I have all body parts back on. New radiator, windshield, relays, fuel pump and dash. Engine bay was painted too. Carpet and most of interior replaced from parts cars.

New engine (except used roller cam). Its been 5 years since I driven the car on the road. Almost finished.

I appreciate the help.

 

Because the ECM does a test on start up to see if the KS is working correctly
If it is not ( or not even there ) it will throw a code and prevent spark advance over 1500 rpm ( run like a pig ) to prevent you blowing your engine up

As noted if you have a 350 you need a 350 MAF knock sensor as it is calibrated specifically for a MAF 350 engine

 

86 Vet 5.7 knock
87-89 Camaro 5.7 knock
90 Camaro 5.7 knock

which one, 87-89?
I have one that has DR017 8210 on the side. I don't know if it was from the 89, 90 or 86. Any help? Thanks to everyone that has replied.

 

NICE reply. Thanks.

 

You need an 87-89 one

 

After some more looking around, I found that Advance Auto sells the same knock sensor, esc module and computer for the camaro 5.0L and corvette 5.7L for the 1986 year.

They didn't sell the 5.7L camaro's to the public that year.

So, just add a new 86 vette knock, 5.7L injectors and new computer ($80.00) with stock vette prom or burnt prom from the guys on here?