Is this a new install, or a setup that's, up until now, been running fine? EECIVs often need several hot\cold cycles to properly map their operation strategy and store it in memory. A new install or disconnected power situation might require some time for this to resolve itself.

John

 

It's a transplant, so power has been disconnected a lot. I'll keep cycling it and see if it gets better over the next week.

 

Just shooting from the cold, IAC?

 

The two things I'd look at first are the coolant temperature sender and the Idle Air Control valve. The IAC can get gummy and sticky from the same stuff that makes the throttle plates brown and dirty. Easy enough to pull off and spray out with carburetor cleaner. While you're at it you'd want to clean the passages and throttle plates too. And old toothbrush is about ideal to help scrub.
You'll have two temperature senders. One for the gauge and one for the computer. Kind of hard to tell if the ECM sender is working correctly without a scanne that will read datastream from a Ford OBDI plug. About the simplest way to check is to see if it is the problem is to swap it for a new one or known good one.
Lastly if your setup is new enough (can't recall off the top of my head) to have an Intake Air Temp sensor make sure it is in the air intake somewhere and plugged in. An IAT doesn't have a large effect on cold starts but can be a factor.
Hardly an all-inclusive list of what could be wrong, just where I'd start looking.

 

My EFI always has a finicky idle if the computer has been disconnected.

Essentially, your A9L will keep track of O2 readings at various throttle set points and will create a table of adjustment values to make the engine run better in the future. If you unhook power for several minutes, those created tables go away.

If it isn't something that simple, other likely culprits would be improper setting of the idle voltage of the TPS, an issue with the IAC motor, or a vacuum leak somewhere.

Phil

 

Something is keeping the EEC from identifying that its in an open loop start up cycle. IAC and coolant sensor are typical culprits.

But since it's a transplant, keep trying a few times, but I suspect the IAC gummed up or malfunctioning.

 

Thanks for the replies. I should be done with the electrical work, so I'll see if the cold start gets better.

Thanks!

 

If you have a battery disconnect or unhook the battery a lot, you can always wire a small gauge, fuse protected feed wire from the ECU directly to the battery. Some folks also do this for radio presets.