Im not sure which adjustment would need looking at. I just replaced my dashpot and adjusted my idle settings before I got the Power FC. Fast Idle cam, dashpot and TPS was just tweaked. Now coming to a stop I get surging but after about 10 seconds it settles and goes back to standard idle. I did the idle learning adjustment when installed Power FC also did it with the AAS turned half a turn.

My o2 feedback is still on, should I just turn that off and see if it changes?

 

Raised those 2 f/c idle adjustments a bit and it may have cured it. I'll see when I take her for a spin.

 

Check your clutch switch at the top of the pedal assembly.

 

I'll check that. Problems got worse on the car. I posted a big thread in the 3rd gen section. Seems more reply there than here.

 

What are your coolant temps during the surge?

 

My temps were staying around 95 c. I have fc thermoswitch so I shouldn't see anything much higher.

 

Put the F/C's back where they were.

Is it happening worse under electrical load (fans, a/c, etc)?

Try unplugging the ISC and see if the problem stops.

 

Yeah I'll be doing a lot once I'm off work. Starting with a compression check due to how horrible the car sounded when the problems rised.

Also my idle was perfect with stock ecu at 1/4 turn on the AAS, I moved it to 1/2 for power fc, I'll move it to 1/4 to see if it helps.

Was going to put stock ecu back on to see if its still perfect but that might be a waste of time.

I got to redo the idle learn process again then I'll do what you mentioned.

I had no electrical load. Other than the fans cycling due to coolant temps at 95c.

 

Sounds like throttle plates.

 

The fans coming on is electrical load, which kicks the idle up. Sounds like the air bleed is not adjusted properly causing the ISC to be erratic when engaged.

 

What about them?

 

Okay I'll try 1/4 turn and do idle learn procedure.

 

What are your VTA1 & VTA2 readings at idle and when it is surging?

 

I'll check it today. After work. If I can get it to surge again.

 

If throttle plates are outta tune it could cause a hunting idle. Your could be off and prolly letting too much air into the tb. Your tps would never know cause it would be at idle position. I dont know how easy it is to adjust on fds but ive seen a few fc guys mess with them and mess there idle up something terrible. Just a thought.

 

100% gone with stock ecu.

 

Okay I installed Power FC again. Pretty much same deal. I posted in 3rd Gen but I figure I would get more help on Power FC forum. Car ran its best first day of installing Power FC. Idled right where its suppose and everything.

I start the car a week later and issues rise. Idle surging when coming to a stop. Driving home I set the first F/C setting to 1050, rest is untouched. Now it goes to 850 when it wants to. Doesnt do the surging but when coming to a stop it does go to 850 briefly and jumps back up to 1200. Idling is always around 1k and sometimes goes down to 850.

There seems to be no steady symptoms that will help me figure it out. Im assuming the mechanical dashpot is making the idle go to 1200 when I stop like its suppose to. But dont understand why it wont stay at target idle which I believe is 750.

VTA1 and VTA2 is in spec. clutch switch is working according to commander. 17 in vacuum when at target idle.

 

"in spec" does not answer my question. What are the VTA1 & VTA2 readings?

There are 2 clutch switches, put your head under the dash, use your hand to push the pedal down and visually inspect the top switch.

 

Car has to be warmed up and idling for vta readings right? When I checked them at idle they were right. But I just checked before I went to work and their

Vta1 .50
Vta2 1.09-1.10

When at idle they didnt fluctuate.

I only see one main clutch switch and it springs back out fast.

 

There is a switch at the top of the assembly that tells the ECU that you have stepped on the clutch and effects idle, the other one is at the bottom of the clutch pedal which is the starter lock out switch that prevents the car from starting unless the clutch pedal is depressed.

If those are the TPS readings at normal operating temp then they are OK.

Unplug the ISC and see if the problem goes away. The UIM does not need to be removed, it is accessible from the top.

I see you said that you have the air bleed at 1/2 a turn, I always adjust it to 1.5 turns.

Check your throttle linkage to make sure it is not gummed up.

 

I did remember that there is two, other one must be hard to see. The one I'm looking for is at very top? The one I pushed was at middle.

If I unplug ISC won't that cause problems? I read that if you unplug ISC you need to set f/c settings to 0 in a datalogic.

Should I try 1.5? Right now it's actually at 1/4 turn.

One bracket is broken on my throttle cable, would that cause it like this? I zip tied the broken bracket to the throttle body where it's suppose to go.

Also should I just remove my ISC and test it? Power fc can't show if its in spec or not.

Thanks.

 

Unplugging the ISC will only cause idle issues if the A/C is on. Do not make any changes to the decel fuel cut settings.

 

Okay I'll try that and report back. Do I leave the mechanical dashpot in place?

 

Leave everything alone, do one thing at a time, so you know what is effecting the idle.

 

Okay I disconnected ISC. Started the car and no high revving when starting. Stayed at 750. Drove around and idle is mostly at 750 but sometimes 850 and then 1000. No load on car. Idle never above 1000 though.

Both clutch switches are springing back up on me.