Shockz

I have an 86 N/A with about 120k miles on it. I took it out of the garage earlier this week, started it up and let it warm up. After about 5 minutes, I took it down the road. I only drove for about a half mile before the car started to lose just about all its power, and after a few seconds just shut right down. I wasn't driving hard at all, the car was never above 4000 rpms.

List of things i've checked.

-Checked the vacuum lines to make sure everything was connected. So far I have yet to find anything loose.

-Cleaned out the throttle body

-Made sure the exhaust wasn't clogged by removing the cat, which had sounded like it had a couple peices loose inside.

-Adjusted the TPS about a week before, setting it at 1.0v during warm idle.


I'm really hoping it is not an Apex seal, but I have a sinking feeling in my chest that its what it probably is. If I could get the car to stay running long enough I could check with starting fluid to see if there was any split vacuum lines.

Any suggestions would be great, as im completely at a loss as to where to keep going. The car didnt have enough power to get on car ramps without stalling out.

Shockz

Further thoughts.

The car seems to idle fine when cold, but is difficult to start, due to flooding out, which has been becoming more and more of an issue. Idle gets more erratic the warmer it gets, to where it simply will not idle without your foot on the gas at operating temp. Engine shaking, loud knocking noise, the works.

This leads me to believe it is the one of the coils. I haven't had a chance to actually take the car out to see if it still has an extreme loss of power when cold, as it is currently on jack-stands. How would I test the coils to see if they are actually bad, without having to buy new ones to see if this removes the problem?

Also, another question. When you have the key turned to the on position, you can hear a sort of "clicking" noise, which emanates from the intake manifold/throttle body. When you hold your hand on top of the intake mani you can feel a sort of ticking/vibration. Is this normal?

K-Tune

iTrader: (26)

Do a compression test and either put your mind at ease or confirm the inevitable.

Shockz

Finally got a chance to do a compression check today. Both rotors turned out surprisingly well, each giving 3 good solid pulses of mid 90s. So now that im fairly certain no internals need to rebuilt, im still stumped.

Spark plugs and wires are new. Plugs are NGK as i've read here that other brands dont cut it at all. I've also redone all the grounding again, grounding out each individual item per the writeup in the archive, except for the ECU. Replaced the neg battery cable with 4g.

I've tried using carb cleaner on each hose to attempt to find a vacuum leak, and still havent found anything there.

While digging, I noticed that the O2 sensor in the exhaust mani was unplugged, but could not find the connector to plug it in to. Is this supposed to be unplugged? And if not, where is the connector to plug it in to?

eurodrift

Have you checked the pump-to-air control valve?
Start cold engine and run it at idle. disconnect the air-to-pump control valve at the air pump. Put a finger over the air hose opening. If vacum is felt, air control valve is defective. I have encountered this once, and that was the problem. just a suggestion. There are way too many TSB's about rough Idle.

Shockz

I'll try messing with that tomorrow. I guess rough idle isn't exactly a good explanation, after it starts warming up, once the rpms drop from about 12-1300 to under 900 is when it starts bucking and trying to stall. Would that valve cause it to not run at all when at oper temp?

eurodrift

could be, wait you are N/a right? that is more for turbo, sorry, but could also be damaged water temp switch, there is a TSB on rough idle for that, don't want you running after a ghost though, I'll do some more searches for that specific seires of issues with the TSB's. I'll get back to you.

florotory

its a long shot but check your ground to your coils. Mine was doing something similar and after 3 weeks of troublshooting i accidentally found out my coils were not getting good ground

jar2

Had the same issue a couple weeks ago. Turned out my tps was completely jacked, and the thermowax was consticting air flow.

Shockz

I cleaned up the fenderwall where both coils are bolted to, as well as extra grounds running to another part of the chassis, and into the battery cable.

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Quote:

I]Had the same issue a couple weeks ago. Turned out my tps was completely jacked, and the thermowax was consticting air flow.

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So it ran fine when it was cold, but once the idle started to drop, it wouldn't stay running at all without throttle? I don't want to replace the TPS, but then find out I spent 200 dollars for nothing.

jar2

Yea. It idled well when cold, then when the engine warmed up and I put it in neutral or stayed in gear the idle would lop between 500-800rpm then just die. I didn;t have to replace the tps, just got a tester light and adjusted it to 1v, and had the thermowax adjusted so it idled a little higher than usual.

Jdrift

Had a very similar issue in my 88 GXL. Was tinkering around with it today after I found one of my secondary valves was sticking. Once I got it freed up I reved the engine a little and drove her a bit, The hose coming off of the cat back to the secondaries blew off. I need to get a back pressure tester, but i'm pretty sure they are clogged.