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Discussion Starter #1
Hope you guys can help me out. My 2004 Canyon has the 5 cyl engine and when I come to a stop light the idle goes way down to around 400rpm according to my tach. It only does if for a brief second and then goes back to around 500rpm. My heater fan slows down when it does this and then speeds back up. It seems like the idle should be closer to 700 to me, because even at the 500 it idles kinda rough. Is this normal? If not, what could it be? Thanks

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I've heard of it being the fan clutch.
Mine had the same problem, I re-flashing my pcm with the gm updates,
One of which is supposed to fix the dive in rpm's while braking.
Fixed me right up! Hope this helps
 

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cleaning your maf sensor and tb, and seafoaming the upper cylinder head usually helps with idle issues!
 

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I had similar where it would dip really low while braking or coasting in nuetral (5 spd) and when I would come to a stop it would pop back up. When I switched to a PTB it fixed it (probably because the PTB was clean). The issue is back for me so I need to clean the throttle body and maf now. Most people have found that cleaning the MAF and throttle body kills the idle dip issue.
 

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Take the throttle body off and use a no-lint rag. Spray it down, let it sit for a minute, and then wipe it all off. As for the maf I believe you just need to spray it and absolutely do not want to touch the filaments in it.
 

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Maybe a dumb question, but do I just get a can of throttle body cleaner and spray down the inside with the motor running or off? How do I clean the MAF?

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You could, but you can clean it much better by just taking it off.
It's not bad, just disconnect the evap line and the connector going to it, and it's four bolts.
As far as the MAF, disconnect the connector and take the two bolts off and pull it out.
 

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this^^ you just have to spray the maf sensor with "maf sensor cleaner" and then let it dry
 

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Discussion Starter #13
Update: I hooked up my scanner and am getting a P0014 code which is the cam actuator. I went to the dealer today and picked up a new one along with oil and filter. I am gonna change all that tomorrow. The other code was P0128 I believe. I need a thermostat as well. Question is...could either of these problems be causing some of my idle issues? I want to get all these issuse that the previous owner let go fixed.
 

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Discussion Starter #15
I kinda thought so. What about gas milage? This canyon does worse on gas than my silverado did.
 

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I have the i5 with Auto and before my new tires, rims & hood I was getting 19-22 depending on how I drove. Now I get 16-19, but it's winter so some of that is purely iat related. The rest is heavier rims and grippier tires.

Once my lift is done and I add a bullmaxx, I'm sure 15 will be where I sit.
 

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I kinda thought so. What about gas milage? This canyon does worse on gas than my silverado did.
That isn't too surprising.

But also useless without numbers.


How to for cleaning Throttle body
http://www.355nation.net/forum/how-performance-maintenance/109-how-change-spark-plugs-clean-throttle-body.html

How to clean MAF Sensor.
http://www.355nation.net/forum/how-performance-maintenance/49-how-clean-your-mass-air-flow-sensor.html

Yours may look slightly different, same principal. It's a 5 minute job. Remove. Spray. Install.
 
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