happyhapka

so to start I appreciate the responses.


my car is a 1986 tpi lb9 trans am and it started doing this problem after I took it to a car was and gave her a bath..


It ran really rough like it was missing a cylinder or 2.


as soon as I limped her home, I took off my distributer cover and noticed I had a electrical burn mark on (white soot) my coil cap and it actually melted the corner of it down a little. it was the corner of tower 6 and 3 of the distributer. so I figured the coil just shorted out so I bought a new hypertech cap and rotor. they sent me the wrong cap as I have screws and they sent me the clamp style. I just swapped out the rotor and the coil over to the old cap which is only a year or so old. it looks fine on the inside. I did this this morning when I got off wrk but didn't start it due to me living in an apartment complex and hey would you know my car isn't as quiet as a prius so I waited till I was off to wrk again. when to start it and it ran a little better as in she didn't want to die on my but still ran rough. (missing a cylinder.) and running pig rich (blowing whitish smk out the tail pipe) my afr is reading very rich. my I only have one 02 which is on the driver side so im thinking it is from that side as the 02 is on that side.


would a ignition control module make it act like this? would it cause a cylinder to not fire. tomorrow I will check to see if I have the right wires where they need to be as I believe the firing order is 1-8-4-3-6-5-7-2
I could have accidently crossed some.
I plan on checking and ohming out the wires. (msd wires)
just wondering about the ICM if it could or would cause this condition.


it is frustrating because the car ran super strong until I gave her a bath.


any imput would be awesome.


also what are some great plugs preferably shorty's..


currently I have msd plugs which are awesome but now could be fouled up. or should I just clean the plugs up and put them back in.


thanks all.

happyhapka

I would like to also mention I just topped her off with fuel right before I gave her a bath. could it also be bad fuel?

Vader

Unless you have headers and a clearance problem, short plugs are not the optimal choice. The plugs can be removed and inspected, and they might provide some clues about the problem. If they require replacement a common AC R43TS or NGK 3547 will do nicely, and have the proper heat range and reach.

If the cap was subjected to arcing and voltage stress, replace it. Yes, you need the "short" distributor cap which is TPI specific. I've also had difficulty finding those for my '86 but they are out there:


Of course the fuel could be a problem but it would not likely affect only one cylinder.

happyhapka

hey thanks vader for the reply...

I got off wrk and took off my msd wires..

by the way I have hooker ceramic headers...

anyway I took off my wires and ohmed them out and this is what I got. bare with me I don't have a ruler with me so its guestimate on the length but here is what I got. let me know what you all think.


1/ 80.2ohm for 1.8 ft
2/ .762ohm for 4.3 ft
3/ 8.8ohm for 2.4 ft
4/ 3.22ohm for 3.2 ft
5/ 89.8ohm for 2.7 ft
6/ 177.6ohm for 4.3 ft
7/ .965ohm for 2.8 ft
8/ 3.25ohm for 3.8 ft

I havnt pulled the plugs yet but am going to now go pull the ignition control modul and go get it tested.. let me know what you guys think.... I think I have some bad wires but I'm not sure.

thanks in advance.

happyhapka

Ok so update... I took the ignition module​ and had it tested... It tested fine. My friend was working so we ran it 8 times.. all pass....

Next I got bat and and pulled the plugs.. I think between the bad wires(if I had bad wires still waiting on a reply) my plugs we're not firing there for got fould up.. that and I had the plugs in for a year and a half or so and this car is my daily as well. My wrk is like 3-4 blocks down the road. I'm thinking between those short distances my plugs got fouled up to the point of not being able to spark so that was my problem..I'm still not sure though.though

Also I ran a spark plug tester light with 2 spark plug tester conjoined into one unit. One is with a light to see if I'm getting voltage through the wire and at the end it is a plug gap tester that you set the gap you want than ground it.. I had spark at every post and was set at .045 as I cranked it.

happyhapka

Here is what the plugs looked like.

Vader

They all appear to be sooted from oil and/or excessive fuel. My eyes are not calibrated, but several of the gaps look pretty wide, or at least wider than the 0.035" spec. They all appear to be a little short on the tip projection compared to a proper stock plug - Are these in stock heads or something modified?

This may not be the root cause of the misfire problems, but possibly the result. Either way they may be beyond cleaning.

happyhapka

I fixed the problem. Replaced both plugs and wires and she runs great again.. it is a little modified and blackened by a little bit of oil but mainly fuel... They were so fould that they wouldn't spark. And I had bad wires...... I used the ngk plugs u suggested.. there also a little shorter than the ones I had...

Still ganna try to clean the plugs as I just got a nice spark plug cleaner.

But I have another project it's stumping me.... I will post in another thread. It deals with an odd situation with a 87 iroc 5.7 tpi... But on my that thanks for all the help.