leaking 9th injector
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leaking 9th injector
would a leaking 9th injector cause idle problems have checked everything a dozen times and something still causes idle and even cruise speed to act up have cleaned and checked throttlebody and all linkage have set time tps and iac also checked for vacum leak
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From: Long Island, NY
Vic
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dont know that it is looking for rpm issues high idle at start up that doesnt go away until shut off and restart or rpm wont drop when foot is off pedal all things like binding cables or throttle body or tps vacum iac timing have been checked and rechecked doesnt always happen sometimes will start and act great next time idle will be 15 to 16 or when driving you let off gas rpm stays high
Safety Car
Joined: Nov 2008
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From: Jacksonville FL
I have the same issue and I dont think its that uncommon. My car will stick on a high idle I believe its related to the IAC and the speed sensor. I notice when mine sticks in a high idle that the idle drops only after my speedo reads zero. And the speedo doesnt read zero until a couple of seconds after I stop.
If I understand the system correctly, the computer keeps the idle speed up for good driveability while moving from the input of the speed sensor. If you unplug the IAC and drive the car you will see what I am talking about. I think you will see your high idle issues stop as well. What the solution to the problem is, I do not know. It will be interesting to watch this thread to see if someone has figured it out.
Good luck!
If I understand the system correctly, the computer keeps the idle speed up for good driveability while moving from the input of the speed sensor. If you unplug the IAC and drive the car you will see what I am talking about. I think you will see your high idle issues stop as well. What the solution to the problem is, I do not know. It will be interesting to watch this thread to see if someone has figured it out.
Good luck!
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Joined: Apr 2002
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From: Anaheim CA
When I had a high idle issue it turned out that the cruise control cable was just a little bit too tight. Try disconnecting the cruise control cable at the throttle body and see if the high idle goes away.
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From: Anaheim CA
The ECM uses what is known as "throttle follower mode". It opens the IAC as the throttle is opened. It uses the TPS to decide how much to open the IAC. That is done so the engine won't stall when you take your foot off the gas and the throttle blades slam shut. The airflow goes from high to zero in an instant. Carburetors have a "dashpot" that does this function.
Pro
Joined: Mar 2009
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From: Middletown Delaware
Thoughts from those that know what they are talking about??
Ozz
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These C4's have lots of places for vacuum leaks to occur. Where was yours? Whats weird with my '93 is after I repair something I think all is good until I drive it a little bit. Automatic trans, in neutral, idles around 825 rpm on a good day....drive it a little bit....back to 975 - 1000....car starts and runs great. I can't get it figured out....checked and checked....and rechecked. I'd like to see a constant idle at 750-800 rpm's in neutral. I don't think this breed will ever do it....
Thoughts from those that know what they are talking about??
Ozz
Thoughts from those that know what they are talking about??
Ozz