4.2L Idle problem
#17
03-17-2006, 02:26 AM
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Update! I had a new exhaust put on my truck a little over week ago and the problem stopped. It's weird. I had the entire exhaust replaced from the cats back, and it hasn't even tried to act up on me? Not Once! 
That's all right with me though.
I highly suspect my problem was a loose baffle rattling around in my Flow 40 that was blocking off the exhaust flow. Now that I think back, my old exhaust made some funky sounds sometimes (like a whistling noise). I think that was the pressure from the exhaust blowing against the loose baffle.
I don't have to worry about that with the new maggy flow that's on there now.
That's all right with me though. I highly suspect my problem was a loose baffle rattling around in my Flow 40 that was blocking off the exhaust flow. Now that I think back, my old exhaust made some funky sounds sometimes (like a whistling noise). I think that was the pressure from the exhaust blowing against the loose baffle.
I don't have to worry about that with the new maggy flow that's on there now.
Last edited by Peacemaker; 03-17-2006 at 02:36 AM.
#18
03-19-2006, 02:58 AM
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#20
03-22-2006, 09:43 AM
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#21
03-24-2006, 03:48 PM
Originally Posted by Peacemaker
Everytime I start my truck when the engine is cold in the morning, it will start up just fine and run really smooth for about 2 minutes. Then my engine will start to shake and miss like it's about to quit.
That lasts 10-15 seconds. Then it clears up and doesn't miss a beat until the next time I start the engine cold.
I've cleaned my IAC valve (nearly spotless at 60k miles), MAF and IAT sensors.
There is no CEL or DTC'S. This has me stumped.
The only thing I can think of is the Flowmaster muffler I'm running now has crapped out. It's rusty and has a loose baffle banging around in there.
I don't think that's the problem though. Because it starts shaking at exactly the same time about 2 minutes after cold start up.
Any help?
That lasts 10-15 seconds. Then it clears up and doesn't miss a beat until the next time I start the engine cold.
I've cleaned my IAC valve (nearly spotless at 60k miles), MAF and IAT sensors.
There is no CEL or DTC'S. This has me stumped.
The only thing I can think of is the Flowmaster muffler I'm running now has crapped out. It's rusty and has a loose baffle banging around in there.
I don't think that's the problem though. Because it starts shaking at exactly the same time about 2 minutes after cold start up.
Any help?
#22
03-24-2006, 09:50 PM
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I've already replaced the dpfe sensor or "proving switch". My idle is ALOT smoother now since I put my stock airbox back on with my drop in K&N. I cleaned the maf and throttle body while I was at it. My Mac intake must have had a leak somewhere I suspect. I dunno. It's running good now, so I'm leaving it alone!
#23
03-25-2006, 03:11 AM
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Originally Posted by Peacemaker
I've already replaced the dpfe sensor or "proving switch". My idle is ALOT smoother now since I put my stock airbox back on with my drop in K&N. I cleaned the maf and throttle body while I was at it. My Mac intake must have had a leak somewhere I suspect. I dunno. It's running good now, so I'm leaving it alone!
Thanks
#24
03-25-2006, 11:45 AM
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I used "non-residual" electrical contact/switch cleaner. You can get it at Radio Shack or Walmart. Just give the maf wires about 5 or 6 quick short bursts. Let it air dry for about 20-30 minutes before you turn the key "ON". A puddle of the cleaner can build up under the maf wires and short them out if you don't make sure it has completely evaporated before you turn the key on.
Just give the maf wires about 5 or 6 quick short bursts. Let it air dry for about 20-30 minutes before you turn the key "ON". A puddle of the cleaner can build up under the maf wires and short them out if you don't make sure it has completely evaporated before you turn the key on.
Last edited by Peacemaker; 03-25-2006 at 11:56 AM.
