Another Engine not Workin'

Don Gaboury

Contributing Member
Use gum cutter, the right kind of course, and clean the valve part, not the motor. I use to spray a lot on the valve, put something over the opening and shake, maybe 2 or 3 times. Put it back on the car and try it. Or you could always buy a new one to go with all the other new parts you got.
 

Scott Harrison

"Growing old is mandatory, growing up is optional"
Staff member
Contributing Member
Member
It's easy, the IAC valve is a MOTOR, what do you think moves the valve.... use gum cutter, the right kind of course, and the valve paert, not the motor.....
Ahhh...that motor! Already done that, and even replaced it with a new one.

BTW, the problem may have been fixed on Sunday.

Apparently the secondary throttle plates were slighty open. Once they were adjusted and IAC reattached, the car runs ok.
 

TroyT

Contributing Member
Member
UPDATE: John came over this past Sunday and we worked on the IAC valve and made idle adjustments, set the timing, and check the internals of the distributor. With John's idle adjustments to the primary and secondary idle screws on the throttle body eliminated the fluctuating idle or idle hunting. It's steady now. However, the car still idles and runs rough with the IAC valve connected. When it is disconnected it runs great. Either way, IAC valve connected for disconnected, the check engine light remains on.
 
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rkite

Member
On my last Mustang I had to replace the IAC valve several times. The original valve lasted 100K but after that they went bad every 50K miles. Cleaning it out with carb cleaner did not work. The other thing that causes idle problems on my 90 GT was O2 sensors going bad.
 

TroyT

Contributing Member
Member
Troy,
Just a long shot. But, how much driving did you do after the adjustments? Could it be the computer hasn’t “relearned” the new settings?
Mike,
I haven't driven it enough after the adjustments for the ECM to relearn the settings. I'll do that this weekend.
 

TroyT

Contributing Member
Member
UPDATE: Towed the cobra to Robert Decker’s shop in MD this morning for him to work on it. He immediately pulled the air cleaner to access the mass air sensor above the throttle body. Using a voltmeter, he checked for power at the wire connector for the IAC valve and he was getting 14v vs. 5v that it should be reading. Also,the small wires across the mass air sensor vanes were turning red when the iac valve wire connector was disconnected. He said they should never be hot. There appears to be a problem somewhere between the IAC valve and the ECU as John Bissell and I discovered a couple of weeks ago.
Hopefully this isn’t a major issue. I’ll keep you posted.
My car is now parked in the shop next to a Lamborghini Diablo. Sorry, I didn’t take any pics.
 
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