86 Trans Am runs Rich, Rough Idle
 

I recently swapped from 5.0L to 5.7 TPI in my 86 TA. This is basicly stock motor only mods - 1.6 rockers and aftermarket FP regulator. Im having rough Idle and excessively rich exhaust, burns the eyes :(..and a Ignition code 43. I Set the basics by the book, Base timing 6-8 btdc, Idle speed, TPS.

The Facts-
Fuel pressure is 40 KOEO, 38 running, 45psi WOT.

Current and only Trouble code 43 - low voltage at spark timing circuit.

Engine is making 14inchs vacum idle, - not great. Then the ESC starts retarding timing and begins to stumble and creates 'rolling Idle"

Spark Plugs foul out, and oil is begining to smell like gas. I unplugged the CS injector running in open loop- no change-.

With that I did ohm test on the Cold start sensor 33 ohms @ 44 degrees. I have another laying around that was 70ohms same temp.:confused: .. I checked for power-no 12volt signal either pin.. I have not found a wiring diagram yet for further diagnosis. Anyone Have Diagram or specs?

Started testing the ESC code- swapped old ESC I had. No change. electrical diag .4ohms on knock signal wire, has 12volt refrence, good ground and .2ohms on the esc signal. I have replaced Ignition module, and MAF sensor thinking these created my problems. NOPE.

I did AIR, EGR, cruise and AC delete properly. plugged manifolds and anything that was vacum controled. I did not modify wiring, PROM or swap ECMS.

ANYONE WITH KNOWLEDGABLE ADVICE, PLEASE HELP ME OUT. I dont have a scanner but i know how to use multimeter

Re: 86 Trans Am runs Rich, Rough Idle
 

You need to get it scanned for codes, Make sure you 02 sensor is hooked up and working, Vacuum leaks, exhaust leaks ect. edit code 43
https://www.thirdgen.org/forums/tech...ion-350-a.html

Re: 86 Trans Am runs Rich, Rough Idle
 

I think a Intake leak could definetly create problems, but it fires right up. Everything is painted so smoking it would be my only option. The O2 is brand new, connected and no exhaust leaks. I also have new 22lbs injectors from FIC on it, so I know they are not leaking.

Re: 86 Trans Am runs Rich, Rough Idle
 

Try replacing the knock sensor.