Hi all,

My 87 GT with about 85K will occasional "miss" or hesitate at idle. Accelerates and drives perfectly, it's just at idle. Never stalled, but it seems to be getting worse.
I have replaced all plugs and wires, distributor (cap and rotor) late last year (seemed to run a lot better right after that) but it's doing it again, same as before.

Any suggestions on where to start looking?

Thanks in advance for any help!

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Tim
'87 GT
Med Red Metallic
81K miles
Bay City, MI

Pull and re-connect the plugs on the ICM, and the pick-up coil. Test the ignition coil and the pickup coil.....it may be a ground problem too.

quote Originally posted by Gall757: Pull and re-connect the plugs on the ICM, and the pick-up coil. Test the ignition coil and the pickup coil.....it may be a ground problem too.

x2

also no check engine light huh?

[This message has been edited by 2.5 (edited 06-11-2015).]

Try the idle air control valve - that fixed mine.

I would also have the fuel delivery system cleaned.

Hope this helps.

[This message has been edited by QCMANAGER (edited 06-12-2015).]

I really appreciate the suggestions, I'll dig into it some more this weekend.

I have no check engine light codes, and I'm wondering if it might be a ground issue. If so, what would be the solution?

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Tim
'87 GT
Med Red Metallic
85K miles
Bay City, MI

quote Originally posted by trivet: and I'm wondering if it might be a ground issue. If so, what would be the solution?

2 things:

1.

Disconnect and clean existing grounds. See the Ogre's cave (Wire Service) if you don't know where they are.

2.

EVERYONE with a V6, please read

[This message has been edited by Gall757 (edited 06-12-2015).]

Check all the grounds in the engine area for good connection.

-

"The 4 main ground ties and positive leads.
#1. (-)Braided block to body ground, deck lid hinge. The main braided strap is critical.
#2. (-)Trans to body. The trans to body is a backup.
#3. (-)Battery to body. Battery (-)post to tray.
#4. (-)Battery to engine block. The big batt cable (-)post to bolt on engine hoist hook.

Positive leads (+)

#5. (+)Battery to starter
#6. (+)Battery to main terminal below C500.
#7. (+)Alternator feed to main terminal below C500.

NOTE. The Ogre has mentioned that if #7 is bad, you will get large voltage drops under load just like a bad ground. We all know what bad grounds do to a Fiero's electrical systems!"
//www.fiero.nl/forum/A...041015-2-052227.html

also
//www.fiero.nl/forum/A...090219-2-082708.html

Wow! Thanks for the great links - I'll be checking this first, as I have some of the other symptoms of bad ground (grounds? Grounding?)

LOVE this forum!!!

Do you have the metal heat shields on the spark plug boots?
Have a look at them in the dark with engine running.

If you see arcing from the shields to the head - take them off.

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