Resolved Idle surge

[Vdubzr32]

This is possibly the millionth Idle surge question asked .
The car idles fine when I start it. When I finally move the car in neutral going down hill the idle climbs alil. Once I stop completely at a traffic light the idle drops back to normal. I would drive on the high way and then put the car in neutral and let it cost the idle is around 1500-2000. i can coast to a complete stop and the idle will drop once I stop the car completely brake held.

Isc- working properly and ohm is reading where it should be.

Fiav- I by passed the it by screwing clock wise the screw type piece with the 4 dots under the freeze plug. Also sealed the water pipes with nipples.

No Vacuum leaks around the 1g 63mm TB, AFPR, Evo 3 Mani., Bov, HBC, brake booster, turbo, wate gate. I sprayed all connections with parts cleaner to see any fluctuations of the idle.

Ecu- I opened the Ecu and there is nothing burned cracked chipped or melted.

Emissions hoses and Egr have been removed. Egr blocked

What else would be in question?


I've read Terry's idle surge page. And many other idle surge pages befor posting This is why I have done all the above

 

[92AWDHX40]

http://www.dsmtuners.com/threads/how-to-fix-your-idle-surge-problem.191137/


http://www.dsm.org/how-tos/tttt/tttt3.html


https://www.ecmtuning.com/wiki/idlesurge

Start with this, and post back on your findings.

 

[Vdubzr32]

http://www.dsmtuners.com/threads/how-to-fix-your-idle-surge-problem.191137/


http://www.dsm.org/how-tos/tttt/tttt3.html


https://www.ecmtuning.com/wiki/idlesurge

Start with this, and post back on your findings.

Thanks I've read those posting and that's why I've done the mods I have done. Only thing I have in question when or how would I know if I have a leaking break booster.

 

[1990TSIAWDTALON]

It is obvious during a BLT if the brake booster is leaking so the next time you do one, listen for air or spray the booster to master cylinder spot where they bolt together with soapy water and look for the bubbles. If it is leaking put a one way check valve in the line or do the right thing and replace it.
BUT...I had this problem also, it ended up being in the tune. If I can find an old file and compare with a new file I might be able to tell you what has changed now so you can check that too. After some good help with my tune it has went away. I wish I could tell you right now exactly what it was but I will have to study all of my logs to see any differences, but it was a tuning issue for me. Good luck! We all hate these things.

 

[Vdubzr32]

It is obvious during a BLT if the brake booster is leaking so the next time you do one, listen for air or spray the booster to master cylinder spot where they bolt together with soapy water and look for the bubbles. If it is leaking put a one way check valve in the line or do the right thing and replace it.
BUT...I had this problem also, it ended up being in the tune. If I can find an old file and compare with a new file I might be able to tell you what has changed now so you can check that too. After some good help with my tune it has went away. I wish I could tell you right now exactly what it was but I will have to study all of my logs to see any differences, but it was a tuning issue for me. Good luck! We all hate these things.

Thanks my brake booster checked out fine an the vacuum line from the manifold to the brake booster has no leaks. It weird how at a stop light it idle normal and when the car is in motion it rises it self. Possibly a tune issue . Let me know if u see any thing in your logs. Should I post a log myself.

 

[1990TSIAWDTALON]

I will have to dig through all my logs and look at every last little thing to see what it different now, but my car did the exact same thing...idled fast while I was moving and settled down when ever I stopped so they are similar problems. I can't promise anything overnight as I have a lot on my plate but I do know after a good re-tune that problem is no longer a problem. If you post a log, there may be someone that can look right at it and see a problem. I am on a work computer so no LINK, sorry, but I hope I can help in some way. The good thing about this forum (well there are ALOT of good things) is that we all try to help each other the best we can.

 

[Vdubzr32]

I will have to dig through all my logs and look at every last little thing to see what it different now, but my car did the exact same thing...idled fast while I was moving and settled down when ever I stopped so they are similar problems. I can't promise anything overnight as I have a lot on my plate but I do know after a good re-tune that problem is no longer a problem. If you post a log, there may be someone that can look right at it and see a problem. I am on a work computer so no LINK, sorry, but I hope I can help in some way. The good thing about this forum (well there are ALOT of good things) is that we all try to help each other the best we can.

Of course I thank you for any help especially the time responding back. I'll post a log of the problem and a video that I took. Thanks again

 

[delval2011]

I experimented with a larger throttle body (3000gt, i believe was 73 mm) and had all types of idle issues. would idle around 1500 and so on. Switched back to the stock 2ga TB boom problems solved.

 

[Vdubzr32]

Fixed was an idle tuning issue another member here cleaned up my idle to perfection

I will have to dig through all my logs and look at every last little thing to see what it different now, but my car did the exact same thing...idled fast while I was moving and settled down when ever I stopped so they are similar problems. I can't promise anything overnight as I have a lot on my plate but I do know after a good re-tune that problem is no longer a problem. If you post a log, there may be someone that can look right at it and see a problem. I am on a work computer so no LINK, sorry, but I hope I can help in some way. The good thing about this forum (well there are ALOT of good things) is that we all try to help each other the best we can.

 

[1990TSIAWDTALON]

Great. The members on here are a great group!