Weird shutter/missfire at idle, cold situation only.

[Vortech347]

So along with my wonderful screaming squirl sound when I start my car when its ice cold... Its started to shudder a hair. Like its missing. It goes away fairly quickly. It does it as I'm idling in reverse out of the driveway. Put it in Drive and I'm off for the day, no issues.

No smoke, no codes....

I changed the plugs to autolite 104's (Had TR55's) and sea foamed it.

Nada...

Edit: also checked the coil packs. They're all ok.

[Ravage17]

it'd be great if you figured this out, mine just started doing the same thing in reverse

[musclemerc]

I would start with cleaning the IAC, datalog the MAF count's to verify it's working properly, and finally remove and clean the egr valve and egr tube

How did you veriry the COP's are OK?

[justbob]

+1 on IAC. Every year it's the same with mine. Does it want to flood while cranking on a cooled down/warm start? It probably will when it worsens.

[Vortech347]

^^^ Interesting. I've had it do that. Sometimes it doesn't want to start.

MAF is good. I'm going to clean the EGR soon.

Still need to find out my stupid starting screech too.

[Richy04]

You can bet on a dirty EGR and throttle body. I've seen this particularly with Chevy's, it amounts to a roughness or a "tuh tuh tuh" sound as you idle out of your driveway or edge up to a red light. A small shutter will usually be felt. The squeal is most likely a dry starter bushing or bad bendix. It do it once in the morning when cold, but really not the rest of the day unless its cold or it sits.
I had belt squeal too but it only came around when it rained. I changed the belt, tensioner and all new idlers and that cured that. These are common issues..

[Bruce Wayne]

I am having this misfire hard start when cold also. It cranks and dosen't want to fire when cold, then it runs like crap for a few minutes until it warms up a bit? Could this be tha IAC , I'm assuming this means idle air control? Does anyone have a part number for this? Thank

[Vortech347]

IAC cleaned and gasket replaced. No change.

I'll work on the EGR.

[cougar9150]

I am assuming intake or MAF cleaner for the IAC. Need to do mine and would prefer not to screw up the sensor.

[CBT]

I am assuming intake or MAF cleaner for the IAC. Need to do mine and would prefer not to screw up the sensor.

I use a brand called CRC, from the shelves of your local Advance Auto. They have a MAF cleaner and a throttle body cleaner. I use the MAF cleaner for the MAF, and the throttle body cleaner for everything else: IAC, PCV, throttle body, and both intakes.

[cougar9150]

I use a brand called CRC, from the shelves of your local Advance Auto. They have a MAF cleaner and a throttle body cleaner. I use the MAF cleaner for the MAF, and the throttle body cleaner for everything else: IAC, PCV, throttle body, and both intakes.

I have a few cans of CRC stuff in the garage. I'm pretty sure I have the MAF and Intake cleaner already along with the 20 cans of brake cleaner I picked up when Advance was have a 2 for 1 sale.

Thanks.

[CBT]

I have a few cans of CRC stuff in the garage. I'm pretty sure I have the MAF and Intake cleaner already along with the 20 cans of brake cleaner I picked up when Advance was have a 2 for 1 sale.

Thanks.

:eek: Good Lawd!! Well brake cleaner works great for cleaning a trans. pan if you change your filter :up: Heck it's probably the same crap in all 3 bottles, lol.

[cougar9150]

I picked up a butt load of brake cleaner when pulled my truck apart . Had about 10lbs of residue from all the leaks on the engine and I wanted to clean everything while the engine was in pieces.