Erratic Idle On Cold Start

gkrcr882

SyTyless......for now!
Re: Erratic Idle On Cold Start

Does it only do this on cold starts, or hot starts as well?
 

WannabaTY

New member
Re: Erratic Idle On Cold Start

Mine does this also but only on cold starts. Once it is warmed up, its golden. I almost posted this today also.
 
Re: Erratic Idle On Cold Start

Usually only when it's the first start of the day, or it's been sitting all day i.e. leaving work.
 

Bullydawg

Mo' Boost Mo' Problems!
Re: Erratic Idle On Cold Start

Bump. I am having this issue. No point in making a new thread. Anyone figure out how to fix this? I cleaned my Throttle Body passages and everything. Only having rough cold starts. Runs perfect once the idle kicks up after a few minutes.
 

Mingus

Member
Re: Erratic Idle On Cold Start

Did you clean / check the IAC? There is an adjustment for it too.
 

Bullydawg

Mo' Boost Mo' Problems!
Re: Erratic Idle On Cold Start

Did both. I adjusted the IAC counts to around 35. I pulled the TB and both cleaned the IAC and the passages (weren't really dirty).
 

Z SKI

Donating Member
Re: Erratic Idle On Cold Start

Vaccum leak that goes away when engine warms up and expands and seals up said leak...
 
Re: Erratic Idle On Cold Start

Check resistance on ECT sensor when cold. I don't know the correct value range. Will check to find out.

This will be the sensor near in the intake manifold near the
T-stat housing.
 

1blkc4

Donating Member
Re: Erratic Idle On Cold Start

I had the same problem it was the cts its cheap and easy.......
 

Bullydawg

Mo' Boost Mo' Problems!
Re: Erratic Idle On Cold Start

Awesome. That was what I was going to look into next. I ordered a couple because I need one asap. I am shipping my truck back to the states in 3-4 weeks, so I need it running. When it arrives, it must be ready for a 5 hour drive back to New Mexico from Dallas.
 

atomicmecha

I hate rust
Re: Erratic Idle On Cold Start

Did both. I adjusted the IAC counts to around 35. I pulled the TB and both cleaned the IAC and the passages (weren't really dirty).

How do you adjust the IAC counts? Mine is reading at 18 right now and has trouble idling.
 

Don W.

Stab it and steer it
Re: Erratic Idle On Cold Start

How do you adjust the IAC counts? Mine is reading at 18 right now and has trouble idling.

The throttle return bumps up against an adjustment screw. Opening the throttle (turn screw in) lowers IAC counts. It's a torx 20.
 

Couger1968

Dazed and Confused
Re: Erratic Idle On Cold Start

I think he means coolant temperature sensor. There are 2 one for gauge send one for ECM
 
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Couger1968

Dazed and Confused
Re: Erratic Idle On Cold Start

Mine hunted like that with my ultimate chip. I never could cure it. The turbotweak chip cured it
 

Rexxenexx

Active member
Re: Erratic Idle On Cold Start

That's interesting. My Ty doesn't start 1st crank if the coolant temp sensor next to the water neck is plugged in. I can keep trying and about 3rd-4th crank attempt it'll startup, rough turn over like its stalling for like 5 seconds then idle smooth. Warm everything is OK. I've replaced the cts, didn't do anything. Also if I unplug the cts next to the water neck it fires up without any issues. Could an air pocket at the cts cause this?
 
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