Surging / Stciking Idle

[Eazy-V]

I recently starting having an issue where the idle surges / sticks at around 2-3k rpm when I come to a stop if my clutch is depressed. The engine surges / sticks at 2-3k rpm then after a few seconds it will typically come back down to normal sub 1k rpm. I noticed that if I put the gear into neutral and release the clutch pedal it comes back to down to normal pretty much right away.

I have a ACT 6-puck clutch/prolite flywheel, so could it be that or a vacuum leak or something wrong with my EcuTek tune? Any ideas?

[norcalpb]

My engine acted like that when I had an exhaust leak.

[humfrz]

Originally Posted by Eazy-V

I recently starting having an issue where the idle surges / sticks at around 2-3k rpm when I come to a stop if my clutch is depressed. The engine surges / sticks at 2-3k rpm then after a few seconds it will typically come back down to normal sub 1k rpm. I noticed that if I put the gear into neutral and release the clutch pedal it comes back to down to normal pretty much right away.

I have a ACT 6-puck clutch/prolite flywheel, so could it be that or a vacuum leak or something wrong with my EcuTek tune? Any ideas?

I suggest you lubricate the automatic choke mechanism with 3 in 1 oil, lubricate the throttle linkage with motor oil, inspect the clutch linkage to make sure it's not binding (and put in new cotter pins) and lubricate all moving joints with axle grease.




humfrz

[DJCarbine]

Originally Posted by humfrz

I suggest you lubricate the automatic choke mechanism with 3 in 1 oil, lubricate the throttle linkage with motor oil, inspect the clutch linkage to make sure it's not binding (and put in new cotter pins) and lubricate all moving joints with axle grease.




humfrz

Should he check the distributor as well? Might have thrown a weight on the mechanical timing advance, or ripped the vacuum advance diaphragm causing a leak.

OP, when is the last time you adjusted the idle mixture and set timing?




But seriously, can you get a datalog while it happens?
Much easier to troubleshoot with sensor data during the event, have you talked to your tuner ar all yet?

[humfrz]

Originally Posted by DJCarbine

Should he check the distributor as well? Might have thrown a weight on the mechanical timing advance, or ripped the vacuum advance diaphragm causing a leak.

OP, when is the last time you adjusted the idle mixture and set timing?




But seriously, can you get a datalog while it happens?
Much easier to troubleshoot with sensor data during the event, have you talked to your tuner ar all yet?

Good follow up!

Oh, my, hold up OP ......... I posted on the wrong forum ....... I thought I was on the 50s car forum ....... I'd better get back over there before that old dude goes crazy looking for the OBDII port, to do data logging .......


humfrz

[alan.chalkley]

Mine was going nuts when the professional apprentice subaru mechanic used way too much throttle body cleaner during two of the routine services.
It fixed itself after a couple of days.

[steve99]

Log whats going on with ecutek cable if you have it

Check ltft it should be arround 5% or less if its like over 10% you likely have intake od exhaust leak

Afr at idle should be pretty close to 14.7

Ignition timing should ve arround 12 degrees after car warms up

The car will have faster idle on cold start , should onlt be for first few minutes then should settle to bg base idle of avout 700

Edit
I see your turbo , so could be a several other things with tune, ie could be speed density tune issue or flex sensor or bov leak, etc incoreectly scaled injecotrs. Best talk to tuner that did the work

[Eazy-V]

Ok thanks for the info, hopefully I have time this week to look into it further.