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post #1 of 16 (permalink) Old 04-07-2009, 08:40 AM Thread Starter
 
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High Idle after Throttle Body Cleaning

Hey all, I have cleaned my throttle body and now my car is reving to about 1700 when I start and stays there. Also, when driving at higher speed it idles at around 2700 when I clutch and stays up there for about 5-10 seconds.

I checked the vacuum hose and it seems snug. I took the filter cover off and put my finger over the mass air flow sensor and it seems to idle normally with it partially covered. I think the engine computer thinks the car is getting more air than it actually is getting.

Also the idle seems to drop when I get to about 40 kph (25 MPH) down to about 2200 or so and again drop back to 1700 when speed lowers to about 20 kph (12 MPH).

The dealer will not do anything unless the check engine light comes on.

Can I do anything or just suck it up?

Last edited by Calgarynewf; 04-07-2009 at 02:08 PM. Reason: More info to add.
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post #2 of 16 (permalink) Old 04-07-2009, 05:44 PM
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How exactly did you go about cleaning it? that might give me a bit more insight to what happened.
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post #3 of 16 (permalink) Old 04-07-2009, 06:37 PM
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It has to be a vacume leak. The dealer should fix it even with out a CEL..



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post #4 of 16 (permalink) Old 04-07-2009, 08:51 PM
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what did you use to clean up the t-body??

id say that
1. something wasnt properly install back
2. vacum leak
or
3. the cleaner that u used wasnt the proper thing to use

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post #5 of 16 (permalink) Old 04-07-2009, 09:09 PM Thread Starter
 
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Used throttle body cleaner from Canadian Tire (Canadian automotive store). Cleaned all the oil that I assume was coming back through the vacuum tube.

I tried playing with the vacuum tube but nothing changed. I will likely have to take it apart and put it back together again.

I did also spray electrical contact cleaner on the MAF sensor but it seems to be reacting to air flow changes.
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post #6 of 16 (permalink) Old 04-08-2009, 03:40 AM
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if it;s reacting to low air flow, what i might suggest is, if you have an air hose, pull out the MAF sensor from your air box, and hold it about three to four inches away from the air line. Spray the air BUT NOT DIRECTLY AT THE MAF SENSOR. if the idle of the vehicle changes when you do this, it means the vehicle is not picking up the right readings at that sensor, and it needs to be replaced.

REMEMBER: point the air line away from the MAF sensor. Direct contact from high pressure air will damage the sensor, so hold it away from the stream of air. The change in air pressure from beside the air stream should trigger it to change it's air fuel mixture. Thus readjusting your idle on the car.
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post #7 of 16 (permalink) Old 04-08-2009, 01:08 PM Thread Starter
 
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OK re-tightened everything and changed the factory tube clamps to ring clamps on the vacuum hose.

How about I just blow on the MAF rather than risk damaging it? That is assuming it isn't damaged.
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post #8 of 16 (permalink) Old 04-08-2009, 07:36 PM Thread Starter
 
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OK I believe the MAF works fine. Don't know why but it is at least responding.

Heres a theoey: What if the PCV is stuck? How do I fix it? Or is there a PCV?

Last edited by Calgarynewf; 04-08-2009 at 07:50 PM.
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post #9 of 16 (permalink) Old 04-13-2009, 02:19 PM Thread Starter
 
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OK for anyone that this may happen, after taking it to the dealer (the tech had 40 yrs experience) he couldn't figure it out so called the Canadian head office and had to re-flash the ECM to get it to idle normally again.
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post #10 of 16 (permalink) Old 04-13-2009, 04:31 PM
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Wow really? the problem was with your ecm?



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