VR6 problems

[BrambleVR6 10]

Hi, I'm new here and I have my first question.

 

I have had the car for a few years now but I haven't used her for roughly a year. Before her short retirement she ran very well, although sometimes cut out at junctions when at running temperature, this was pretty rare though.

 

Since using her again she pretty much cuts out at every junction.

 

I have done the ECU reset in the knowledge base, changed the plugs and leads, cleaned the throttle body and ISV to no avail.

 

I'm not sure what to do next, any advice would be very appreciated.

 

Thanks.

 

Edit: The car in question, very dirty after sitting on my mums drive for a few months.

 

Edited October 29, 2011 by BrambleVR6

[floppyman 0]

Have you had it connected on vagcom? If not you should do that, or else you will be changing parts after parts.

[BrambleVR6 10]

No not yet, I have only just convinced the Mrs to let me have two cars on the road.

 

I dont know what happened to my original message, it keeps getting deleted :shrug:

 

Edit: Errr, its back.

Edited October 29, 2011 by BrambleVR6

[Mike Edwards 0]

Coked up idle stabilisation valve. Fixable using car cleaner and cotton buds, you just have to get the thing off first.

[BrambleVR6 10]

I did that today mate, did't make any difference. If I unplugged the ISV and ran it what will happen? If its faulty will it correct the problem?

[CazzaVR 0]

My bet would be the ISV. Do you know anyone else local with a known working one? Alternatively, there are some brand new pattern ones on Ebay that I've used with no probs whatsoever. £50-60 IIRC.

 

Otherwise, it could be the MAF.

[Mike Edwards 0]

If it is the ISV, the reason it's cutting out is because it isn't working. So disconnecting it should give exactly the same symptoms. MAFs tend to mess up the fuelling when they go wrong, so it it's just cutting at junctions go with that first. Might be worth checking the wiring to the ISV while you're there.

 

---------- Post added at 06:36 PM ---------- Previous post was at 06:27 PM ----------

 

Quick paranoia moment: When you say you cleaned it, did it move freely with no more than light pressure from a fingernail afterwards? If it didn't, either it's still jammed up with crud, or the drive mechanism has broken.

[RW1 0]

No not yet, I have only just convinced the Mrs to let me have two cars on the road.

If you haven't connected VCDS then you haven't done the ECU reset properly. You need to do the Basic Setting part. That sets up the throttle with the ECU. If you don't, one of the effects is cutting out as you describe.

 

There is no need to disconnect the battery and do the driving part again. Thats sorted. Just warm the engine oil up past 80'C and do the Basic Settings procedure part with the correct ECU measuring block selected.

 

.

[BrambleVR6 10]

Thanks for the info.

 

I think I have found the problem, its the ISV. I disconnected it and straight away ran very smooth, before it wasnt as settled as it is now. It also idles at 900rpm instead of 600.

 

I guess I will be buying one of ebay if you recommend them, thanks.

[floppyman 0]

RW1 would you please explain how to do that? I allways thought basic settings didnt work on the corrado?

[BrambleVR6 10]

The ECU reset is a bit strange anyway, it didn't make the slightest bit of difference to how the car ran.

 

I have never heard the need to do that on any other car either, although I'm not saying its wrong.

 

---------- Post added at 07:07 PM ---------- Previous post was at 07:06 PM ----------

 

Probably because I didn't complete it like you said :bonk:

[floppyman 0]

On newer cars you do need to adapt the throttle body with basic settings but thats for drive by wire throttle. Ive never managed to get basic settings to work on the corrado, thats why I would like to hear a bit more from RW1

[RW1 0]

Its as written in the procedure. It is not like the motorised later throttle aka later Mk3 Golf or the later "ADY" 8v Corrado which has a motorised idle. Basic Settings places the ECU into a specific offset condition from which the engine sensors can be measured. The ECU needs to know where the idle position is on the C. VR6 throttle by reading the Throttle Position Sender. Without this being done, the ECU works just on the MAF and ignores the Throttle Position Sender signal. Hence the stalling. Due to tolerances, its not always apparent there is anything different and on some, they don't stall. There isn't a positive "I've done it" if thats what you are looking for. You just let it sit idling for the prescribed time of 2 minutes or more.

 

The time in Basic Settings mode specified is a minimum and the oil temperature has to be above 80'C. The last time I did it last weekend, I left the engine running in Basic Settings for 10 minutes, but 2 minutes minimum after the throttle blip is quite sufficient and it shouldn't be less than 2 minutes. There is no upper time limit. The procedure I wrote states 85'C to ensure instrument error is avoided.

 

Basic Settings is part of the 10,000 miles service when the service is carried out in full at VW. Doesn't matter how many times it is done as long as the procedure I wrote thats in the Wiki is followed and the correct Measuring Block is selected for the engine ECU fitted while doing it. As it says in the procedure, doing only the 1 part, ie. the drive , is a waste of time. Its acheives nothing and in fact can make the engine driveability even worse in some cases.

 

The battery disconnect is not necessary unless the MAF or ISV or Lambda Probe or Throttle Position Sender is changed. With the battery being disconnected, then you do the drive in the 10 minutes while the ECU is in coarse adjustment "learning" mode where it sets up such items as the Lambda stored readings for idle, mid throttle & full throttle in Measuring Block 6 fields 2, 3 & 4. (NB. Disconnecting the battery for other reasons such as storage or maintenance on the Corrado, means it needs the drive sequence & Basic Settings.)

 

After the 10 minutes, coarse adjustment of parameters stops and the ECU continues to adjust in a very fine adjustment to compensate for petrol quality/brands or the Lambda changing due to age. Aim being to keep emissions as good as possible.

 

PS. If I don't do B.S. on mine after a battery reset, it stalls at junctions or in one case at 55 mph in a sharp left turn while changing down a gear. Not much fun with no power steering at the time!

 

.

Edited October 29, 2011 by RW1

[floppyman 0]

Wow... Thanks alot RW1... Ill look for that wiki... Once again... Thanks :)

[BrambleVR6 10]

Now that is some knowledge, nice one.