Dicky

Hi Folks, I thought I'd post an update. I had a new Lambda probe fitted yesterday and all seems well so far: no cutting out; no fruity smells and mpg up from 18 to 32 on a steady run. 8) Fingers crossed she's sorted now. In summary (and in order of completion): 1. fitted new Lambda probe. [faulty] 2. cleaned ISV. 3. replaced inlet and exhaust manifold gaskets. [probably not necessary] 4. replaced ISV. [probably not necessary] 5. replaced cracked exhaust downpipe. [definitely needed] 6. replaced Lambda probe (s/c to earth). [possibly killed by overfuelling as a result of the cracked downpipe] I think all the problems I had were a direct result of the cracked downpipe - just goes to show that you shouldn't get too hung up on blaming an obvious component. Yesterday was the first time in 6 months she was a pleasure to drive - reminded me of the good old days! :luvlove: I'll report back in a week or so.

tonytiger, the garage aren't charging me for diagnostics - they're a good bunch of guys. The car doesn't generally smoke. It has done it 2 or 3 times when coming on the throttle after a long period on the over-run (probably worn valve oil seals?) - even then it was only a brief puff of smoke. I think (hope) the head is in good shape. I've kind of got stuck on the thought that maybe there is a wiring issue or that the overfuelling caused by the cracked exhaust downpipe has somehow damaged the lambda probe. When I had this problem before and the probe was replaced the car was running like a dream.

The good news is that this probe is in warranty. However, I don't think the garage will believe it could be faulty again! What could kill a Lambda probe?

Thanks for the reply dr_mat, The Lambda probe was replaced some time ago - I can't remember when off the top of my head. Even so, the ECU has been reset by the garage several times. When the garage replaced the downpipe they told me they hadn't reset the ECU. When the fault recurred I assumed the new downpipe hadn't fixed the problem I disconnected the battery overnight believing the ECU fault codes would be reset. (This was a couple of weekends ago.) If this action does indeed reset these codes then the two codes I have posted are new.

OK Guys, I've just got back from having the diagnostics checked and there were 2 fault codes: 00537 008 – Lambda Control Regulation Limit Exceeded 00525 029 – Lambda Probe G39 Short Circuit To Earth I’m on my 2nd new Lambda probe after the first new probe failed. Could the new probe have been damaged by the leaky exhaust downpipe (which was replaced a couple of weeks ago)? The fault wasn’t cured by replacing the pipe – even though it did have a crack in it! The probe (as I have previously mentioned) only has 2 wires coming out of it (the other 2 being cut off). The mechanic who fitted it wasn’t there but another said that the other 2 wires are for probe heating. Are these not needed? Can you just disconnect them without any effect on the system? Why would they be there at all if they are not necessary – or is this a generic probe that fits lots of cars? (It is supposedly a genuine VAG item by the way.) Anyway, does it look like I need yet another new Lambda probe? Cheers, Richard.

I did that and it made no difference - that's why I assumed an ECU reset wasn't as simple as disconnecting the battery. So it looks like I've still got a problem! I'll get the diagnostics looked at on Monday and post the results - hopefully they'll shed some more light on the problem. What about the MAF? Could a fault with the MAF look like an air leak?

Thanks for the replies. I did mean MAF :roll: The fuel consumption was normal when I had the Lambda probe replaced and the car was fine for a while - it has since reverted to the same symptoms. I'll get the diagnostics checked on Monday and let you know what it says. I'll also ask the garage to reset the ECU for me too. I assume disconnecting the battery overnight is not sufficient to reset the ECU? I wouldn't have thought so but could the leaking downpipe have damaged the new Lambda probe? Why would the garage have cut 2 of the wires off? What is an AFR meter? :oops: Cheers guys.

Hi folks, my (’93) VR6 often cuts out when rolling to a halt at junctions (it starts and idles perfectly every time – including after cutting out). The garage’s diagnostics test indicated an air leak (a high Lambda value indicating the engine is running lean). The MPG are down to about 21 on my run to work where I would normally see around 31 MPG. Oil and water temperatures are ‘normal’ at ~ 110° and 90° respectively. There is often a fruity smell outside the car – possibly unburned fuel?? I’ve searched the Forum and found several references to cutting out at junctions but with no definitive cause being identified so I thought I’d post this with all the details I can remember. (In fact, I have already applied many of the posted solutions.) I've cleaned (twice) and subsequently changed the Idle Stabilisation Valve (ISV). The inlet and exhaust manifold gaskets have been changed. The exhaust down-pipe had a crack in it and has also been replaced. According to the garage’s workshop manual this sequence of repairs should have solved the problem. In addition, I’ve had a new ignition switch, 2 new Lambda probes, new ignition leads, new ECU and fuel pump relays. (On the subject of Lambda probes – how many wires should it have and what should they all do? There seem to be 4 wires on the connector but 2 have been cut.) I still have the cutting out problem and have now noticed a loud hissing noise from the damper (connected to the ISV). What does this part do and should it make a loud hissing noise? I'm fairly sure it was never this loud but I can't be 100% certain. I've cupped my hand around the damper and this reduces the severity of the hissing but I cannot feel any sucking or blowing from the part! I can’t see any obvious splits in any hoses. I went to look at a (’94) Golf VR6 with the intention of listening to the damper but it didn’t have one, or an ISV. Are they not fitted to later engines or was it removed by the previous owner (the guy who owns it now bought it as is). Since everything downstream of the MFA has been replaced I’m not sure where to look now. Could a faulty MFA manifest itself as an air leak? Now I’m running out of ideas - any help would be appreciated as I’m rapidly running out of money! Thanks.

Just wanted to drop a note to thank John for his expertise and quality service. John was really helpful and the pipe looks and sounds great. I'd recommend this system to anybody and I recommend John to supply and fit it.

Yeah I did tonytiger. They are the pukka VAG leads and cost me £76.02 inc vat.

Thanks Timo, I just checked the coilpack (didn't realsie it had the numbers written on it :oops: ) and the numbers I was given were the coilpack connections. Flippin' stealers :!: :roll: I traced the HT leads out of the coilpack and you're right (and as I suspected). Cheers Dicky

Hi guys, can anyone confirm the VR6 cylinder layout please? Looking from the front of the engine I've been told: 6 4 2 1 3 5 FRONT Is this correct. Cheers Dicky

Thanks to Gavin for his headlight loom - it did exactly what it said on the tin. Easy to install and good comms. A pleasure to do business with. Cheers mate. 8) Dicky

Hi guys, sorry for the delay with the HT lead part numbers - I've been away. So here they are: 1032702 1032701 1032698 1032696 1032704 1032703 HTH Dicky

Storm - sorry I took my time :roll: The coil pack is £202+vat from FORD. I don't know how this compares to VW?