richcz28

My check engine light is on and I have just rebuilt my engine top to bottom with new everything, and I mean everything. The modifications include edlebrock headers, and a torque/efficiency cam. The car is a 1984 z28 h.o. The AIR tubes have been removed as well as the smog pump. I am told my computer is dead by the machine shop that worked on my block. Unfortunately I cannot locate a garage that actually has equipment to test my car, nor do I have any friends with which to swap ecus. My carburetor is completely rebuilt also and is the stock carb.

My symptoms include. (this is everything currently wrong with the car I realise some things may be completely unrelated to my ecu)

-Rough idle sometimes decreasing down to 500rpms with the volts dropping

-Choke is always on, except I took it out temporarily

-Some days my car will idle at 1500rpms spontaneously

-Poor gas mileage 9-15mpg over the course of 4 tanks

-Sooty exhaust pipes

are there any tests I can do on my car to help diagnose this problem. I have worked with tuning the carb and idle screw. My vacuum is 14 inches at idle. My timing is 16 degrees advanced at idle and 29 at rev.

thanks

Toehead

Read the codes using the paperclip method.

richcz28

Could you please explain the paperclip method?

richcz28

Alright I figured out the "paper clip method" Turns out I had a brand new temp sensor that was malfunctioning and telling the comp my motor was at -20degrees C all the time causing a rich running condition. I replaced the sensor and retuned the car. Now I am having a recurring problem every morning when i first drive my car. It will run fine for about 5 minutes idling at 700rpms. After this it begins to idle about 1500rpms for about 5 minutes. During this time the check engine light comes on for about 2 minutes. The computer stores a code 45, aka running rich. After these five minutes it idles normal. Also my car stalls around tight corners I found out today when i was playing with it. Help!