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rickbtbird
08-30-2006, 03:35 PM
Well I think I have a bad plug. I get a slight shake at idle and if I monitor the exhaust I can see it there too. So I threw a timming light on it and the timming marking is jumping up and down. BTW where the heck is the timming graudation on these 95's? What's the best way to isolate a bad plug without pulling each one?

MSG419
08-30-2006, 11:48 PM
It's tough to determine exact causes of a miss. But one thing you could try: With the car running, pull each wire off the coil pack one at a time to check for strong spark and also listed/feel for a major difference in the way it runs.
Check for vacume leaks as well as this can foul you up good. Boost gauge should be around 20 at idle.

Good luck.
Mark

rickbtbird
08-31-2006, 10:48 AM
It's tough to determine exact causes of a miss. But one thing you could try: With the car running, pull each wire off the coil pack one at a time to check for strong spark and also listed/feel for a major difference in the way it runs.
Check for vacume leaks as well as this can foul you up good. Boost gauge should be around 20 at idle.

Good luck.
Mark
Thanks for the advice. I put the timing light on each wire and did a visual. I really didn't see anything there. Iím sure your suggestion would be a bit more conclusive. I'm a bit apprehensive of pulling wires one at a time while the engine is running because of a possibility shock. So would it be better to do that with a restart? Also, did the 95ís have the timing graduation scale around the harmonic balancer? My 90 has one but the 95ís missing.

rickbtbird
09-01-2006, 07:07 AM
When I start the car the idle goes up to about 1500rpm and slowly decreases to about 800-850 and when it gets totally warm it goes to about 600rpm's. Then I get a constant vibration or thumping noise in the driverís side cockpit that doesn't seem to be visible or auditable in the engine compartment. When I drive the car and engage the tranny sometimes there appears to be a constant thud at lower RPMs at the same interval.

This car had a clutch replacement done last year. From what I can understand from the repair notes this was done because the slave cylinder had a hydraulic leak so they did all of it since the tranny had to come off anyway.

Ok a bit more diagnostics here. I pulled off each plug wire and the idle went worse on each removal. I also did a cylinder balance test with the code reader and it passed that diagnostics test. I put the timing light on again and monitored the light intervals on each cylinder. I don't know if this is a problem but some of the light intervals coming from the coil were faster then the others. Now I know that these ignition systems supposedly spark on both the power and exhaust stroke but some didn't flicker the light as fast as others. For example

Would appear to flicker on the power stroke and only sometimes on the exhaust.
Flicker only on the power
Flicker only on the power
Flicker only on the power
Flickers on both
Flickers on both


Is it possible this problem is the new clutch job replacement went bad or worse maybe the lower bearings are starting to go?

rickbtbird
09-01-2006, 08:24 AM
Here's something else that just happen. This morning on my way to work, I stopped at the ATM and left the car running. When I got back I sat in the driver's seat and turned the steering wheel and the RMP's took a dive and almost stalled.

Sweet90SC
09-01-2006, 09:33 PM
is your PS pump binding up a bit...that'll cause the engine to stall....

ThunderDave
09-01-2006, 10:15 PM
The way the idle goes up and then gradually drops, makes it sound similar to a bad IAC symptom. You could try unplugging it and see what it does. A good IAC unplugged will kill the engine. I bad one allows more air in and increases the idle. AS for the other symptoms, I'm still thinking about it. :rolleyes: ;)

rickbtbird
09-01-2006, 11:38 PM
is your PS pump binding up a bit...that'll cause the engine to stall....
I'm still stumped on this thumping noise I'm hearing at 650rmp idle. I spent about 2 hours under the car today. I only hear it when I'm sitting in the driverís seat but the source appears to be from the engine compartment, although I can't hear it there. Because I get more shake at that low idle as well, I'm thinking that one of the motor mounts might be broken.

Issue resolved with the drop in idle when turning the wheel. I pulled all the plugs and wires and installed new OEM ones. I also did a compression test which passed as well. The old plugs were shot and might even be the original (96600 miles) ones... :eek: I don't know. The pick up is even better now and I do notice much more punch in lower RPM's. Nothing like a fresh set of PP and wires to put you back in the seat.

While I was under the car I griped a hold of everything I could grab to see if it was loose. Nothing in the front of the car but I did find a loose rear passenger side shock. It was slipping back and fourth on the bushing. My girl friend pointed out to me when I got the car home that the rear end was noisy. I thought it was the trunk because it was missing a rubber stopper (which I later found in the spare tire compartment). So I unbolted the shock from the rear lower control arm and I put in two rubber insulator washers (one on each side of the shock) and tightened it down. I did the other side for good measure. Good thing the woman nags at me or I would have never noticed it. Now it even rides better then before and really rides more like my 90SC now.

rickbtbird
09-01-2006, 11:39 PM
The way the idle goes up and then gradually drops, makes it sound similar to a bad IAC symptom. You could try unplugging it and see what it does. A good IAC unplugged will kill the engine. I bad one allows more air in and increases the idle. AS for the other symptoms, I'm still thinking about it. :rolleyes: ;)
The idle only goes way up after a cold start and slightly up after a warm start.