Idle Hang ????
Idle Hang ???? Ok well here is my problem. Once in a while not every stop but when i come to a complete stop and push in the clutch the idle will hang at 2000 then go to 1500. Then after about a minute it will come down to normal. What would cause this to happen. I have all boltons in sig. I did clean the maf about two weeks ago it did not change anything except to maybe smooth out the idle a little.
Im confused on this one. I thought this only happens to cammed cars. Btw only type of tuning is rear o2 delete 160 thermostat and a gear change. No performance tuning.
Im confused on this one. I thought this only happens to cammed cars. Btw only type of tuning is rear o2 delete 160 thermostat and a gear change. No performance tuning.
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From: Decatur, TN (N-W of Athens)
Carb cleaner the TPS, throttle plates, and the spring area. Then penetrating lube them all. See if that clears it up. If that's not it, then you can rule out mechanical.
Is this a M6 swap car?
I had that same problem with mine after swapping in the T56. I used a A4 pcm that pcmforless deleted all the A4 stuff out of. But because it was still an A4 operating system it was looking for the PRNDL switch to tell it that it was in gear. Because it wasnt seeing this, it was assuming the car was in park or neutral. A simple swap to an actual M6 pcm got rid of the problem for the most part. It was still there but barely noticeable.
M6 operating systems use mph to determine wether the car is under load or not. So after the swap, the idle would only hang untill I got below a certain mph, then drop immediately.
When people swap to an M6, there's two wires going to the PRNDL switch that are only connect when the shifter is in park or neutral. Swappers simply connect these together to make the hatch release work again, but makes the pcm think that the car is still in park or neutral.
I had that same problem with mine after swapping in the T56. I used a A4 pcm that pcmforless deleted all the A4 stuff out of. But because it was still an A4 operating system it was looking for the PRNDL switch to tell it that it was in gear. Because it wasnt seeing this, it was assuming the car was in park or neutral. A simple swap to an actual M6 pcm got rid of the problem for the most part. It was still there but barely noticeable.
M6 operating systems use mph to determine wether the car is under load or not. So after the swap, the idle would only hang untill I got below a certain mph, then drop immediately.
When people swap to an M6, there's two wires going to the PRNDL switch that are only connect when the shifter is in park or neutral. Swappers simply connect these together to make the hatch release work again, but makes the pcm think that the car is still in park or neutral.
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From: Decatur, TN (N-W of Athens)
Its not the ECM, it's a box in the ECM that says "X for Manual" and "O for Auto" (O meaning Open box, no X to tag it). The rest of the Auto stuff was lock up and line pressure. It's a simple "oops" to miss changing that one thing. It doesn't have any nice fancy table like the other stuff :\
There is no Manual or Automatic ECM. Same thing down to the reflashable EPROM used. It's software that's different.
There is no Manual or Automatic ECM. Same thing down to the reflashable EPROM used. It's software that's different.
I know you can select manual or auto with the LT1edit, but did not fix the problem for me. Manual cars do not have the two wires going from teh PRNDL switch to the pcm, but auto's do. When the pcm see's a signal from wires that arent supposed to be there, it assumes that the box selected is wrong and reverts. Thats why guys like Brian @ pcmforless dont just check the box and leave it at that. They disable all the A4 controls and codes to make the pcm 'think' its controlling the correct stuff.
I forgot to mention in the above post that when I swapped pcm's, I also swapped the powertrain wiring harness. THE SWAP SOLVED THE PROBLEM. Checking the box in Lt1edit alone didnt do squat.
Im almost positive that checking the 'box' only corrects the speedo for the difference in VSS pulse signal. Everything else still needs to be done manually, unless you swap the pcm.
I had to go back to the A4 pcm with the swap to a th400 fwiw.
I forgot to mention in the above post that when I swapped pcm's, I also swapped the powertrain wiring harness. THE SWAP SOLVED THE PROBLEM. Checking the box in Lt1edit alone didnt do squat.
Im almost positive that checking the 'box' only corrects the speedo for the difference in VSS pulse signal. Everything else still needs to be done manually, unless you swap the pcm.
I had to go back to the A4 pcm with the swap to a th400 fwiw.
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Joined: Oct 2006
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From: Decatur, TN (N-W of Athens)
$10 says the HARNESS solved the problem, then. With what you all said. And if all the stuff is removed from the ECM, there's nothing for it to revert BACK to. I don't know the PCM4Less folks, but I can tell you this, they're not stupid. Another $10 says they take a Manual EPROM dump, tune it how they want, and upload it to the ECM. So there is no real deleting of A4 stuff, it's a total over write. What do I know, I only programmed my own chip.
first the car came this way 6 spd from the factory so i can rule all that out. I will start cleaning those this weekend and see if that clears up the problem. thanks guys.
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