MAF sensor - clean or replace - petrol 2.5T - EML error
 

Hello

2006 2.5T petrol

I have the Engine Management Light displayed, and error message 'Engine System Service Required'.

Main dealer read error codes and has replaced crankcase breather hose. All good for 24 hours, but then problem returned.

Fast idle on cold start not working, idle speed can be erratic/pulse. Better when engine is warm.

Re-Read codes and now told MAF sensor readings are too low, cost for part £280 plus fitting; also possibly hose from turbo? Codes cleared for now.


Is it worth myself cleaning the MAF sensor with a spray, WD40 Contact Cleaner for example??

Anything to watch out for in the cleaning process?

Can I replace the MAF myself or does it need any programming or will trigger any other error codes.

Replacing is rather expensive https://www.fcpeuro.com/products/vol...280218088#desc

Cleaning it is tricky, to access the actual tiny sensor wire, it needs removed from the housing - has two security screws. Can remove them slowly by grabbing them with a pliers on the edge

At no moment can use anything other than specific spray on a MAF https://www.autozone.com/miscellaneo...11oz/36011_0_0

I have run v70 petrol turbos since 2003 and ran them for over 320K in total. Historically, I ignored advice about cleaning MAF's with a cleaner. I used an electrical contact cleaner from Halfords. The more you clean them the more they appear to need cleaning. After about 150K on my T5 I was cleaning the MAF every 3-5 months, but its became a 5 minute job start to finish. When I tried the same procedure on my R it worked the first time, but within a month the light/error message were back and no amount of spraying resolved the matter. I was forced to buy a new MAF which sorted the car.
Some here have reported they has totally killed their MAF on the first cleaning - perhaps they used WD 40 which is 100% NO NO. Just be warned cleaning might not improve matters.

I dremmelled a slot in the screws to use a normal slot screw driver, as I did not have the security torx to remove the screws.

Cheers
Bob

Aaalmost missed this thread...

In summary:
Mass air flow sensor "fault" (which may simply mean that it reads differently from what's expected)
Erratic idle..

Have you tried cleaning the throttle?

It did sort the issue once and for good in my case.

Thank you for advice.

New MAF sensor fitted and all good, back to normal.

I assume that the MAF sensor controls the cold start idle speed, as this is back to sitting at 1,500rpm for 30 seconds or so, and then reduces down.

Hi The MAF does read the air inlet temp,
Dave

To oldsaab93:
1) CONGRATS on fixing your vehicle
2) How many miles were on the car when the MAF went bad?
3) Would you please post the exact codes the dealer pulled?
thanks

[QUOTE=oragex;2563960]Replacing is rather expensive https://www.fcpeuro.com/products/vol...280218088#desc

Oragex, I've just clicked on the link in your sig ... that's a great selection of helpful videos ... now bookmarked.

Georgeandkira

MAF went bad at 150,000 miles, car is a 2006 model so 13 years old.

Sorry, I do not know the error codes, but was told MAF levels were reading too low. Hope that helps you.

if you watch diagnosedan on youtube he proved that cheap MAF displayed widly innaccurate values compared to OEM, so make sure it was a good branded one