So like the title says my engine only runs at around 30-40 degrees BTDC (its way off the measuring plate which is why i've given a range), when in reality the optimal ignition timing should be around 10 BTDC. Now I would leave the problem alone, but it bothers me (because its wrong and weird) and also occasionally at a complete stop the engine stalls. In hopes of fixing this problem I replaced the entire distributor unit, My timing chain, cam sprocket and chain guide (which was independently verified that I correctly placed the timing marks, that #1 piston was @ TDC on compression stroke and the rotor was pointing to #1 cylinder). I even tried a new MAF sensor. My father seems to think that by process of elimination the problem could either be: My CPU, Knock sensor or a severe vacuum leak which eludes my discovery. Anyway, mighty Camaro gurus please help me!???

*Fyi my timing light works well..so that is not the problem either!

Car= 1986 sport coupe
Engine= 2.8L V6
Transmission= 700R4
Gears= idk? (Stock)

 

Maybe you are not disconnecting the right wire ? It's well hidden in the loom near the fan box. Just a thought.

 

Maybe you are not disconnecting the right wire ? It's well hidden in the loom near the fan box. Just a thought.

 

Here's what the EST wire looks like on my car.


Say could you do us a favor and fill this out .It helps us answer some of your questions. This way with just a glance we know what you’re working with. If you don't know just put "stock" and we can help you figure it out.

Simply click on USER CP near the top of the page.
then
EDIT YOUR DETAILS
then fill in the last 4 lines at the bottom of the page.
Car =
Engine =
Transmission =
Axle/Gears =


Anyone that has not done this should.
Its a common courtesy.
Thanks

 

If there is an ECM in your car than you also need to set the "Minimum Idle Speed" to go with the timing adjustment.

Timing like this.

Start car and idle until the car is at operating temp. Disconnect the EST wire, adjust timing, reconnect EST wire. Shut off car .

Then,

Setting Minimum Idle Speed.

1)Jump the A to B terminal under the dash in the ALDL Terminal as seen below.
2)Turn the key on but do not start it
3)You should hear a slight ticking coming from the IACV.
4)What 45 seconds then unplug the IACV with the ignition still on.
5)Disconnect the EST wire and remove the jumper.
6)Start the car.
It may be necessary to hold the throttle open slightly to prevent the engine from stalling.
Allow the engine to reach normal operating temperature.
7)Connect a tachometer. I used a digital timing gun with RPM feature.
8) Adjust the minimum idle speed using the throttle stop screw.
9) My Chilton’s says set it to 700rpm in park on an 89 TBI 5.0 auto.(yours might be different)
10) When done shut the car off and reconnect the EST wire.
11) Plug the IACV back in.

Take it easy on the car for the first day or so.
Drive it normally on the street and highway to allow the ECM to re learn the new parameters.
The car will feel better and better as you do this.


By the way, doing these two things is the "Base" the ECM uses to run the car.
Its basically the first thing to do when trying to get the car to run correctly.

When setting the "Minimum Idle Speed" you are also resetting the "Idle Air Control Valve". That's very important, especially for those having idle problems.

 

It might be useful to verify the position of the timing marks on the balancer. They have been known to slip/move. This can be done with a piston stop and measurement or by observing the crank snout keyway in relation to the TDC timing mark.

 

No i defintely have the right wire

 

Ron U.S.M.C. , thanks for the picture of the EST wire (i defintely have the right one) and instructions on setting the idle speed. i know that will help with the engine stalling problems, but what I'm more concerned with is my ignition timing being way off and my car still running good. do you think the idle speed adjustments will fix that?

 

I did this with the new harmonic balancer that i bought and it passed the test. the timing marks are correct on the balancer

 

ive seen it more than once