Weird Idle

[mndsm1]

My idle keeps jumping up and down from 1000 to 500 and then back up and down, sometimes tending to die when im coming to a rolling stop. When its just sitting and idling it wont die though.

 

[Turbo Talon DL]

My idle keeps jumping up and down from 1000 to 500 and then back up and down, sometimes tending to die when im coming to a rolling stop. When its just sitting and idling it wont die though.

Here are a few things to check for in order to remedy this problem:
-Hook up your coolant lines to the bottom of the throttle body for the FIAV
-If you have a SAFC then adjust that until you have no idle surge
-Perform a boost/vacuum leak test and fix all leaks including throttle body shaft seals
-Fix any leaks after the MAF
-Adjust base timing as close to 5* as you can get it, set to 800 RPM with BISS
-Hook up the ISC motor
-Make sure the closed throttle switch is contacted when the plate is ALL the way closed
-Use datalogger and check for DTCs

Enjoy

 

[kanderson]

Is your bov recirculated?

 

[mndsm1]

Is your bov recirculated?

No its not recirculated, but I have the MAF-T setup to blowthrough, the isc sensor isnt on the tb..it screwed out somehow and pulled the plug off with it and I havent replaced it yet, but even after I noticed that was off it would idle normally.

 

[kanderson]

Did you change anything recently or did it just start doing this on a whim of its own?

Is it possible that your MAF translator could have gotten unplugged?

No boost leaks?

How does it perform on throttle?

 

[mndsm1]

It started doin it randomly out of nowhere, its perfecetly fine when im driving. Just gets weird when I am coming to a stop or just sitting.

 

[Razor_nl]

as found on vfaq.com:
Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[Chibi]

Hello All,
Sorry this is my first post on here and Im starting off asking a question. I also am having this problem and figured this would be the best place for the best advice. I have a 96 stock GS. The other day when pulling into my driveway I started to get a low idle. When starting up its fine and then within a minute or so it starts a flexing between idle RPMs. My friend is saying it is probably a sensor problem however he is not sure which one it could be. Also to note, I have been having a small amount of smoke coming out of my exhaust for some time. I have recently replaced all spark plugs and wires as well as my up and down O2 sensors.

After reading a few post on here, which I must are are very informative, I can see that it could be a vacuum hose prob, or sensor. Is there anything else I should look for?

Thank you very much for being such a informed group. Good luck
Stephen

 

[bobby180360]

i had the same problem with mine but it turned out to be a bad maf, idk if this helps but maybe u got a bad maf