Bogging/stalling when coming to a stop, irregular power.

[partypants]

Now, when the coils are replaced\verified operating correctly w\ ALL cylinders firing fully & you're still experiencing engine "bog" (engine idle speed drops below the set idle speed then returns back up to set idle speed) when APP is released & PCM has switched to idle speed control from dashpot speed control once MPH has dropped below approx 4 MPH & in a no-load situation (in neutral), we'll need to find out if this is due to either the PCM's VCT control being too slow to advance the cams back to full advance (0* so engine will be outputting full TQ at low engine speed) or if this is due to PCM's idle speed control (where the TB has a part in this).
The VCT control is easy to test by simply unplugging the VCT solenoids BEFORE starting the engine (this will keep the VCT solenoids in full advance position so when engine is started up & oil pressure comes up & unlocks the cam phasers, the cams should stay in the startup position thus "locking the cams in place". Now you will get a VCT Solenoid Circuit Fail DTC as the PCM won't see the +12v power at the VCT terminals in PCM so just clear this after running the test). Then start the engine as normal then drive the car as normal to see if the engine still does the "bogging" when coming to a stop w\ trans in neutral--if it still does the bogging then this eliminates the VCT system as a contributor which then points to the PCM idle control\TB operation which will then need further testing to pinpoint the exact issue whether it is the TB, the tune or both.......but if it clears up then you'll know the VCT system is the cause which will then need further testing to pinpoint the exact issue within the VCT system.

But you need to rectify the coil issue 1st before doing this test or going any further. I understand your situation thus the need to get your daily back on the road & return your loaner car but some patience here is needed as well.[/QUOTE]
So I just tried doing this, there were no codes and it changed nothing.

 

[partypants]

Now, when the coils are replaced\verified operating correctly w\ ALL cylinders firing fully & you're still experiencing engine "bog" (engine idle speed drops below the set idle speed then returns back up to set idle speed) when APP is released & PCM has switched to idle speed control from dashpot speed control once MPH has dropped below approx 4 MPH & in a no-load situation (in neutral), we'll need to find out if this is due to either the PCM's VCT control being too slow to advance the cams back to full advance (0* so engine will be outputting full TQ at low engine speed) or if this is due to PCM's idle speed control (where the TB has a part in this).
The VCT control is easy to test by simply unplugging the VCT solenoids BEFORE starting the engine (this will keep the VCT solenoids in full advance position so when engine is started up & oil pressure comes up & unlocks the cam phasers, the cams should stay in the startup position thus "locking the cams in place". Now you will get a VCT Solenoid Circuit Fail DTC as the PCM won't see the +12v power at the VCT terminals in PCM so just clear this after running the test). Then start the engine as normal then drive the car as normal to see if the engine still does the "bogging" when coming to a stop w\ trans in neutral--if it still does the bogging then this eliminates the VCT system as a contributor which then points to the PCM idle control\TB operation which will then need further testing to pinpoint the exact issue whether it is the TB, the tune or both.......but if it clears up then you'll know the VCT system is the cause which will then need further testing to pinpoint the exact issue within the VCT system.

But you need to rectify the coil issue 1st before doing this test or going any further. I understand your situation thus the need to get your daily back on the road & return your loaner car but some patience here is needed as well.

I did this and there were no codes and nothing changed.

 

[partypants]

ALSO, something odd I just noticed.... On my JLT CAI, I have a different coupler (the end that goes on to the throttle body) than in the pictures and videos I see on it. Mine doesnt have a place to attach the hose for the PCV valve, and where the hose attaches to the motor, theres just a breather. I find this very odd.

 

[JEWC_Motorsports]

Its not odd. Its a known mod

 

[partypants]

Its not odd. Its a known mod

From what I was reading though (albeit not a lot), it seems like people mostly do it when they put blowers on. Which given the fact that I have a boost gauge thats not attached to anything, Ive always assumed whoever owned the car before me either WANTED to or HAD a SC on the car.

 

[JEWC_Motorsports]

People do it to keep the oil vapors from going back thru the intake tract. Oil in the intake tract can cause a lean condition.

 

[partypants]

So even more odd... I drove it to work today, a ~25m drive, and 0 bogging upon deceleration.

 

[DieHarder]

So even more odd... I drove it to work today, a ~25m drive, and 0 bogging upon deceleration.

With or without everything hooked up normally?

 

[partypants]

I drove last night with the vct solenoids unplugged and nothing changed, so i hooked everything back up.

 

[dark steed]

I drove last night with the vct solenoids unplugged and nothing changed, so i hooked everything back up.

Have you disconnected the battery and let it relearn idle, etc? It could have “learned” the bad habits with the faulty COP/plug…


Sent from my iPhone using Tapatalk

 

[DieHarder]

Possible you had a poor connection somewhere that got fixed by fiddling with connectors. Drive it for a while to see if symptoms change. If nothing, then call it good.

Would be best however if you could recreate it. Then you'll know what subsystem it belonged to for future reference.

 

[partypants]

Have you disconnected the battery and let it relearn idle, etc? It could have “learned” the bad habits with the faulty COP/plug…


Sent from my iPhone using Tapatalk

Not since changing the coils

 

[partypants]

Possible you had a poor connection somewhere that got fixed by fiddling with connectors. Drive it for a while to see if symptoms change. If nothing, then call it good.

Would be best however if you could recreate it. Then you'll know what subsystem it belonged to for future reference.

It seems like its intermittent now, i took my coworker for a quick ride and it did it once but not the rest of the ride.


Well, driving home it was still happening.

 

[LikeabossTM]

I seem to recall, when futzing around with my IDS years ago, that there was a misfire monitor profile relearn procedure - or some such thing.

Don't know if that might apply to whichever gen/engine is being discussed here, but it might be worth Googling.