MAF sensor & Coolant Temp. Sensor - Dealer Diagnostic - Confused!

[GAZJ69UK]

Hi..I replaced the MAF sensor on my Y reg 2001 Mk4 1.9 SE TDI PD, after having loss of power problems at 2500-3000rpm, but didn't really resolve problem.  Put car into my 'stealer' for 70k service and they come up with diagnostic fault and said MAF sensor & Coolant Temp. Sensor faulty.  I explained to dealer that cant be MAF as already replaced and it was new part, they also said I needed coolant temp sensor!   Does anyone know if it is normal for the MAF sensor to show on their diagnostics?  Is it because after the new part was fitted, the diagnostic codes weren't cleared?

I got them to replace coolant sensor, they re-diagnosed and fault came up clear...Cost me £280 all in for service and coolant sensor, probably been ripped off??  Is the coolant sensor easy to locate and fit?

ps...they also tell me that my diagnostic plug is missing along with tandem pump leaking slightly and that engine undertray (side) missing???  Help.....  where is tandem pump and can I buy and fit the bits that they claim are missing?

Any advice...cheers  Gaz

[welshgar]

wow, where are you based m8y?? sounds like you got a very "picky" stealers there!!!

the vag com diagnostics sometimes misdiagnose the faults so thats where it has picked up your maf again probably.....although the temp sensor is also another  "problem area" with our cars. i dont know where or how to change one as mine hasnt gone (yet  ) the DIY will probably be in a haynes or on a help thread somewhere (sorry to be vague)

as for the diagnostic plug being missing??? how did they find and clear your codes if they couldnt find the plug to put their vagcom into??? . the port for it is underneath your centre consol, above your ashtray!!a bit of plastic hides it away......tandem pump? never heard of one of those, and your engine undertray!! well 50% of cars have one and 50% dont. they are plastic and often fall off, no bother really.

£280 sounds expensive but thats usually a normall ish price for a service in VW.

good luck with finding your "plug"...sorry i couldnt be of more help

Gareth

[Flipmode]

Hello.

I'm a novice really and not that well rounded on the mechanics of our cars, i have a 1.8T GTI and had similar problem with my temp sensor last year. My car had problems starting again if i switched her off after a short journey, and also the revs were all over the place when the car was idle. I took it to an independent garage who said it was temp sensor, not sure exactly where it was located/how simple to replace, but the part cost about £20 and now my car is fine. Was something to do with the car thinking the outside temp was colder than it actually was, therefore used more petrol than required during the start up which then led to my car burning  this extra fuel off soon after...hence the random revving. not sure if this helps mate, good luck.