Still having idling problems after H/C/I

[NKau]

Not sure what my next step should be. Finally got the car to stop throwing CEL's by plugging the charcoal canister back in (not hooked up otherwise). I still cannot get the car to hold and idle. With the engine cold, I can start it, it will hunt for a while, then idle pretty decent right around 800 rpm. Once you take it out on the road and warm it up, it will not try to idle at all on deceleration, just stalls out, at which point you have to hold the gas to the floor to get it to fire again, and then pedal it to keep it running.

After swapping in the new h/c/i engine, I did upgrade to 24lb. injectors, a 75mm Pro-M Maf, and a 65mm throttle body.

Where do I go from here? Could the TPS on my used TB be causing some of this?

 

[mustanggt5pt0]

Could be the air idle control motor Before I got a new one, it would idle fine cold etc. If I ran to the store then came out and started it back up, it would surge and die. And sometimes as you describe, slowing at a stoplight and letting it idle on the way down, it would die on me then I'd have to pedal it to keep it going.

 

[time only]

My own experiences with H/I/C upgrades is that if everything else match ( Injector,Mass Air Sensor etc,etc ). The placement or what in front of the Mass Air Sensor is the deal breaker. I will make sure there is a straight shot of tubing going into the MAS,No bend or any of angle tubing there,also you could try turning the MAS all the way up to get the best idle.
On my stock engine motor it works fine with a slight bend in the tubing going into the MAS,but when I change to the GT40 setup it give me hell until I put the cone filter directly in front of the MAS. Now I get myself a power pipe and it idle fine.

 

[NKau]

Could be the air idle control motor Before I got a new one, it would idle fine cold etc. If I ran to the store then came out and started it back up, it would surge and die. And sometimes as you describe, slowing at a stoplight and letting it idle on the way down, it would die on me then I'd have to pedal it to keep it going.

I might try swapping the AIC motor since I have the old one still laying around from the old TB. Thanks.

 

[NKau]

My own experiences with H/I/C upgrades is that if everything else match ( Injector,Mass Air Sensor etc,etc ). The placement or what in front of the Mass Air Sensor is the deal breaker. I will make sure there is a straight shot of tubing going into the MAS,No bend or any of angle tubing there,also you could try turning the MAS all the way up to get the best idle.
On my stock engine motor it works fine with a slight bend in the tubing going into the MAS,but when I change to the GT40 setup it give me hell until I put the cone filter directly in front of the MAS. Now I get myself a power pipe and it idle fine.

What kind of MAF do you have? I actually just used the factory airbox and intake ducting with my new Pro-M; this may be part of the problem?

 

[jrichker]

You guys with idle problems could same a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first post has all the fixes, and steps through the how to find and fix you idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix. :

 

[time only]

What kind of MAF do you have? I actually just used the factory airbox and intake ducting with my new Pro-M; this may be part of the problem?

I have both a Pro- M plastic and a C & L all set up for 30# injector,the stock air box should work fine since it is still a straight shot of tubing going into the MAS,like the man said,it is just checking off things that could go wrong and sooner or later you will get it right.