Hunting idle since battery removed / alarm installed...

[jrleech]

Here's the story.....

Took battery and tray out to remove blockage from drain plug, re-fitted battery and alarm/immobiliser kicked in.

Didn't have a remote for the alarm, so today had installer come and remove it and fit a Cobra Cat 1 system. All seemed well, car now starts!!

Problem is, when I put the clutch in or sit at a junction, the engine idle searches a lot before settling. If I rev the engine then lift off, it'll drop to 500rpm, then 1200, then 600, then 1100 etc...., eventually settling back to normal.

Sometimes it'll dip so far it stalls itself.

I've read some posts here that point to the lambda sensor, but it seems too much of a coincidence.

Is there a 'learning system' that has got messed up? After having the battery reconnected, the first hour of the car's running time was spent at idle... could this have caused it?

The installed assures me that his installation couldn't affect the idle, (he's immobilising the fuel pump power and ignition circuit).

Any ideas? Or is it likely to be the 02 sensor?

Thanks,
Jon

 

[madvw]

after reconnecting the battery after a long time, the ECU performs a throttle adaptation automatically. If it isn't left to complete before the car is started, it has to figure it out over time.

In addition, as you already stated, there is also an ecu re-learn period too.

My guess are that your problems are due to an incomplete adaptation. You could always disconnect the battery for another 20 mins, then re-connect. Turn the key to position 2, but dont start the car. wait about 2 mins to be on the safe side. Then start the car. See if that helps at all.

 

[jrleech]

Thanks for the suggestion... I'll give it a go in the morning.

Pulled off the error codes from the car this evening, got the following:

Controller: 4D0 907 551 F
Component: 2.8L V6/5V MOTR HS D02
Coding: 04201
Shop #: WSC 06325
8 Faults Found:
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent
01249 - Fuel Injector for Cylinder 1 (N30)
26-10 - Output Open - Intermittent
01250 - Fuel Injector for Cylinder 2 (N31)
26-10 - Output Open - Intermittent
01251 - Fuel Injector for Cylinder 3 (N32)
26-10 - Output Open - Intermittent
01252 - Fuel Injector for Cylinder 4 (N33)
26-10 - Output Open - Intermittent
01253 - Fuel Injector for Cylinder 5 (N83)
26-10 - Output Open - Intermittent
01254 - Fuel Injector for Cylinder 6 (N84)
26-10 - Output Open - Intermittent
18020 - Engine Control Module Incorrectly Coded
P1612 - 35-10 - - - Intermittent
Readiness: N/A

Not sure if they're recent, or some old codes.... I've cleared them anyway, I'll see if they re-appear.

Anyone know what they actually mean?

Thanks,
Jon

 

[madvw]

aah, you have VAG-COM. In that case you may as well manually kick off a TB Adaptation without disconnecting the battery then.

 

[jrleech]

Hi...

I do have VAG-COM, but I need to learn how to use it properly...

Removed the battery this morning, gave it an hour (charged the battery too), and did as advised.... didn't make a difference.

Went for a good drive, still hunting.

Took it to my local Audi specialist (independant), he plugged in his diagnostics unit and looked at lots of signals while revving etc... Eventually he said 'maybe one of the lambda sensors is faulty' (no codes for it though). Booked it in for next week.

Drove away, and it's cured!! No idea what he did to it, but it works now! Well happy.... can cancel the appointment now.

Cheers,
Jon

 

[joost]

Glad to hear you got it sorted, bit of a nightmare you've had!

[ QUOTE ]
Took it to my local Audi specialist (independant)

[/ QUOTE ]

Just out of curiosity, who/where is the indy? Was looking for one a couple of months back (I'm just outside Blackburn).

 

[jrleech]

They're called Naze Lane Garage, on Naze Lane, Freckleton (other side of Preston). It's a reasonable sized garage, room for about 4 or 5 cars at a time, seem to know their stuff.

Car is still running fine /ubbthreads/images/graemlins/smile.gif

I'd spent 2 days at the weekend with the Claybar and polish, and it was looking mint. Today I parked it under a tree and when I came back the whole car was covered in sap!! I was gutted, the paint felt like it had a million bubbles of sap on it (well it had). Washed it as soon as I got home and fortunately it came off easily, was getting worried for a minute though!!

Cheers,
Jon