Car won't hold idle at startup, but fine when warm

[eboy0]

This seems really weird, since I swapped in my optima yesterday the car won't idle at startup, there's ignition but it just starts and dies, so I have to give her some gas(which I know isn't good). Is this just because my ECU was reset?
Optima reads 12.60v.
After the initial forcing of start, but car seems to idle normally, the usual slight bouncing of 100rpm in both directions. DSMLink reads normal values aswell, except LrnIdleAdj and IscPosition which I'm still working out.
Any suggestions? Could this be related to tempsensor?

 

[IslandTSI]

Yes it could be. Did you mess around with any vacume lines while you were replacing the battery? A leak could be part of the issue

 

[hpram99]

I know this may sound retarded.

Make sure you have a very good solid -non corroded- connection to the battery terminals. And when bending those cables around a bit, make sure you didn't rip a ground wire out of it's crimp ring.

You have no idea how many times I've seen a poor connection will wreak unholy havoc on little bits of your engine management system

I told you it was retarded >_>

 

[eboy0]

Nope, it was a simple take out old, put in new. Maybe the ecu needs time to learn everything again..., and hpram99, the positive looks kinda crappy, and the negative looked even worse, so I bought one of those spider web grounding kits.

 

[StealthyDSM]

CLEAN those terminals!!! this just happened to a local kids car here that i helped him with, i used a battery cleaning tool that has piece that goes on top of the terminal and you turn it about 3-4 turns and the opens to expose a wire brush the is used to fit through the wire harness part. like stated above this can be small stupid and yet retarded head ache. i even use grease on the fittings to help prevent corrosion on them.

 

[eboy0]

Well the battery is 2 days new... so the terminals are perfect, it's the positive cable and negative cable which are looking a little old, but they never gave me a problem before.

 

[hpram99]

Uh.. no, you obviously don't need to clean the terminals, you might need to clean off the original battry clamps that connect to the posts.

Just because it wasn't giving you problems before, doesn't mean it's not giving you problems now.

Replace the wires, let it re-learn the idle, and let us know a week later

I just put my optima yellow top in myself, so I'm going through the same thing as you now. Except mine probably dies because of that fuc*ing open-air BOV.

 

[daren_p]

I bad idle at startup can also be FIAV related but I think this is more just idle oscillation & not actual stalling (but maybe could be if other parts are out of adjustment). If you have DSMLink log the coolent temp. If you have issues up to around 127, then after your idle is okay Id look at the FIAV.

 

[eboy0]

Now the opposite seems to be happening.... I reset the ecu and complete opposite is happening. When car starts up, iscposition reads 30-40, and lrnidladj is at 137, once car warms up, iscposition begins to drop into the low 10's..

 

[GVR4592]

How do your fuel trims look?