little idle issue

[aaronr]

02 Chevy 4l60e 5.3l
O.k. here is my issue when truck is idling it has a miss. It all started when I did swap from my stock 5.3 to forgen 5.7 and it had the same problem but come to fine out the rings never seated so I pulled the motor and put a stock 5.3l back in the truck. I'm looking for things to check. I replaced the sensors in the throttle body, spark plugs, wires, the coil packs, and that didn’t help. I'm not getting any codes at all. When I start the truck-up for the first time its little rough then clear-up to a miss. You would think when turning on the a/c it would fall on it face with a miss but it doesn't keep idling fine with very little miss. I would think if I had a vacuum leak or intake leak my long fuel trims would be maxed out. The other thing is it doesn't start missing until come to complete stop after driving. Do you guys think there is ground issue and one sensor just not reading right at idle? It's not the tune because it is the stock tune on the truck. Any ideas would be help full that would cause this.

[2boosted]

Is a stock engine no mods?

Is a tuned file?

Do you have Hptuners?

[pl4yboy]

Same coil packs or different on each motor?

[aaronr]

Is a stock engine no mods?

Is a tuned file?

Do you have Hptuners?

It did the same thing on built motor but i throught from rings not sealing. Now I have a 2003 5.3L with no mods and running my 2002 stock 5.3L tune. I have EFLive. Is there somthing you want me to log?

Same coil packs or different on each motor?

The Built motor I ran my 02 coil packs and on the 2003 5.3l running all the sensors and the coil packs that came with the motor.

[aaronr]

Morning bump for more ideas.

[2boosted]

I'm incline for the ground issue.

Try to clean, clear, and relive grounds.

Last time I had a weird miss fire, It came to be two cables and 3 plugs melted.

You already did that, so no point looking it again !

Can you enable in you scan program the miss-fires error per cylinder?

Allen Nelson did this on my tune-Scanner, and I was able to pinpoint the problem.

My tune at first had this error disable !

[pl4yboy]

I'm incline for the ground issue.

Try to clean, clear, and relive grounds.

Last time I had a weird miss fire, It came to be two cables and 3 plugs melted.

You already did that, so no point looking it again !

Can you enable in you scan program the miss-fires error per cylinder?

Allen Nelson did this on my tune-Scanner, and I was able to pinpoint the problem.

My tune at first had this error disable !

I agree, getting HPT or some other scanner hooked up and verifying which cylinders are misfiring would be my first step. If it is on one certain cylinder, that may narrow it down.

[aaronr]

I logged the miss fire and didn't show anything.