Cold engine = poor idle

[nello]

When cold my truck starts up but then sputters and then dies quickly. I wait a couple of seconds then try again, it starts up but then idles poopy, but it stays running. When running while cold if I step on the gas or shift into a gear it dies again. If I let it idle and warm up it seems to run fine for a while without a lot of idle hop. That is until it gets hot and then the rpms jump from 625-675. Any suggestions? I've got a datamaster but I haven't figured out what I'm looking at.

 

[gjp]

Re: Cold engine = poor idle

check the iac counts. check vac lines, Fp and timming. when its warm is it ok?

 

[jjorgensen52]

Re: Cold engine = poor idle

Is it throwing any codes? My truck did that when the ECM coolant temp sensor went bad and was reading hot all the time

 

[nello]

Re: Cold engine = poor idle

Is it throwing any codes? My truck did that when the ECM coolant temp sensor went bad and was reading hot all the time

Interesting, I just replaced my stock sender with an autometer one for a gauge pod but I'm still using the stock wires for ECM purposes on the sender.

 

[jjorgensen52]

Re: Cold engine = poor idle

Interesting, I just replaced my stock sender with an autometer one for a gauge pod but I'm still using the stock wires for ECM purposes on the sender.

There are two senders, one on the driver's head (which reads for the stock gauge), and one on the intake (for the ECM). If you're doing a gauge, you can either change the one on the head, or add another one on the passenger's head. (or what I did, change to a jimmy waterneck and then you have another sensor port on that). I forget the ohm range on the ECM sensor, but it is specific and it won't switch between hot and cold run modes if it is off

 

[nello]

Re: Cold engine = poor idle

Figured it out guys, thanks a lot. Turns out it's not my trucks fault for me being a dumb ass. When I put my gauge pod in with the water temp I removed the stock sender unit and replaced with autometers sender. I simply spliced the stock wires for the sender into the new one cause I thought it would keep telling the ECM everything was good and keep my gauge cluster working. Not the case, gauge cluster yes but dropped Ohms to ECM and it couldn't operate correctly making it run like dookie.