MAF sensor MY00???
23 March 2006, 10:05 AM
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MAF sensor MY00???
Hi all,
I suspect my MAF on MY00 turbo is on its way could anyone please clarify.
It will idle 800 rpm most of the time after the initial warm up, but occasionally it will drop to 100 rpm and on two occasions it has actually stalled.
If I blip the throttle the revs do drop fast to around 1100 rpm then slowly to around 800 prm.
When driving though if I engage the clutch when coming to a stop whilst in gear the revs do drop fast all the way own then usually climb back up to around 800 rpm.
I disconnected the MAF sensor though yesterday whilst the vehicle was running and it DID stall - I thought if the map was faulty or on its way the vehicle should stall?
I have no records of the MAF ever being replaced, it presumably is five years old and the green dot mentioned in other threads does not seem to be visible on the outside of the sensor itself - suggested an older sensor.
Any comments would be appreciated in this matter, thanks in advance.
I suspect my MAF on MY00 turbo is on its way could anyone please clarify.
It will idle 800 rpm most of the time after the initial warm up, but occasionally it will drop to 100 rpm and on two occasions it has actually stalled.
If I blip the throttle the revs do drop fast to around 1100 rpm then slowly to around 800 prm.
When driving though if I engage the clutch when coming to a stop whilst in gear the revs do drop fast all the way own then usually climb back up to around 800 rpm.
I disconnected the MAF sensor though yesterday whilst the vehicle was running and it DID stall - I thought if the map was faulty or on its way the vehicle should stall?
I have no records of the MAF ever being replaced, it presumably is five years old and the green dot mentioned in other threads does not seem to be visible on the outside of the sensor itself - suggested an older sensor.
Any comments would be appreciated in this matter, thanks in advance.
23 March 2006, 11:05 AM
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Somertimes reading the ECU won't show anything, as it has "learnt" the poor flow and believes all is normal.
You best bet is to borrow a known good MAF to see if it improves things, as it may be your idle control valve thats causing problems.
If your anywhere near Lancashire I've a spare one on my garage shelf, which you could try.
You best bet is to borrow a known good MAF to see if it improves things, as it may be your idle control valve thats causing problems.
If your anywhere near Lancashire I've a spare one on my garage shelf, which you could try.
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23 March 2006, 01:24 PM
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Is there any way of testing the MAF?
When I had my new turbo fitted and remap, the MAF was changed but it showed no signs of failure before hand so I don't know whether the spare I have works or not.
Didn't realise it was in the box with the original turbo until a week after it was fitted so didn't get chance to ask why it was changed.
When I had my new turbo fitted and remap, the MAF was changed but it showed no signs of failure before hand so I don't know whether the spare I have works or not.
Didn't realise it was in the box with the original turbo until a week after it was fitted so didn't get chance to ask why it was changed.
23 March 2006, 01:27 PM
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Originally Posted by ReggieMY99
quick test, unplug MAF while engine running, if it stalls its probably ok
if it surges down in revs and then come up again and settles MAF is knackered
if it surges down in revs and then come up again and settles MAF is knackered
23 March 2006, 01:29 PM
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The only way I know of "testing" a under reading MAF, other than swapping it with a known good one, is to have a live reading taken from a main dealers hand held ECU reader - something the've been known to charge an hours labour for !
Last edited by SCOOBY TOWERS; 23 March 2006 at 01:38 PM.
23 March 2006, 01:55 PM
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Originally Posted by scooby_matt
That's the best thread hijack i've ever seen
28 March 2006, 12:34 PM
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Well all to keep you updated I have removed, cleaned with brake fluid and re-attached the idle control valve after a tip off from SCOOBY TOWERS - THANX, the car so far is now running fine.
I did do an ecu check it came back with both faults with the maf and idle control valve, but seem as I have disconnected both of these sensor whilst the engine was running it would!
My next plan is to do an ecu reset, monitor the vehicle and then do another ecu diagnostic check - hopefully all then should be clear!
Thanks all once again for your input!
I did do an ecu check it came back with both faults with the maf and idle control valve, but seem as I have disconnected both of these sensor whilst the engine was running it would!
My next plan is to do an ecu reset, monitor the vehicle and then do another ecu diagnostic check - hopefully all then should be clear!
Thanks all once again for your input!
28 March 2006, 12:59 PM
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Originally Posted by BOB'5
If the MAF is 5 years old I would change it anyway.
28 March 2006, 03:51 PM
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Originally Posted by Heple
What do you do with your old ones?
or do you do silly annual milage?
Craig
. Maybe if more people did it there would not be as many "my engines fooked
" threads!to be fair it is a 400BHP+ P1, with an induction kit so A) maf will be a bit more susceptible to water/dirt/vibes B) engine is a bit more on the edge than a standard one anyway.
No less than Mike Wood posted on here recently (in a P1 specific thread) you should change them regularly.
Always have a spare in my boot, just in case, and there is 1 or 2 in the garage as well.
28 March 2006, 04:01 PM
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Originally Posted by p1mark
Why the shock. its called looking after your car . Maybe if more people did it there would not be as many "my engines fooked " threads!
to be fair it is a 400BHP+ P1, with an induction kit so A) maf will be a bit more susceptible to water/dirt/vibes B) engine is a bit more on the edge than a standard one anyway.
No less than Mike Wood posted on here recently (in a P1 specific thread) you should change them regularly.
Always have a spare in my boot, just in case, and there is 1 or 2 in the garage as well.
. Maybe if more people did it there would not be as many "my engines fooked " threads!to be fair it is a 400BHP+ P1, with an induction kit so A) maf will be a bit more susceptible to water/dirt/vibes B) engine is a bit more on the edge than a standard one anyway.
No less than Mike Wood posted on here recently (in a P1 specific thread) you should change them regularly.
Always have a spare in my boot, just in case, and there is 1 or 2 in the garage as well.
MAF failure on MY99/00 is very common and i change mine every 20,000miles.
Yearly just seamed a bit extreme in my circumstances but its all about making sure you minimise weak points that could cause engine failure and if you feel you have to do yours yearly to minimise engine failure then who am i to criticise you.
I would advise anyone with a MY99/00 to change their MAF if mileage (of the MAF) is unknown or they have any suspicions to its accuracy.
You only have to search through numerous threads on here (as mentioned) to figure that out.
Craig
Last edited by Heple; 28 March 2006 at 07:30 PM.
28 March 2006, 05:25 PM
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I know you were not making any digs mate no worries. sorry if my post seemed stroppy as it was not meant to be
It may be a bit ott, but im not prepared to run the risk. £80 is 2 tanks of petrol or a bloody good night out thats all. Its nothing in the general scheme of things for a bit of security. as said, with an induction kit i'm likely to not be giving them as easy a time as with an o.e airbox.
It may be a bit ott, but im not prepared to run the risk. £80 is 2 tanks of petrol or a bloody good night out thats all. Its nothing in the general scheme of things for a bit of security. as said, with an induction kit i'm likely to not be giving them as easy a time as with an o.e airbox.
28 March 2006, 08:10 PM
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In my opinion the cars most at risk from maf failure are std P1, std Sti5/6 and mildly tuned MY99/00 UK.
Std MY 99/00 UK will 'normally' quite happily survive on an under reading maf, they just go a bit faster due to the leaner mixture...lol ...and as long as you don't hold them flat out for long durations nothing untoward happens. This is due to the low state of tune and very rich mixture run on these cars as standard producing a very wide safety margin.
A highly tuned (say 340+bhp) UK/P1 or Sti will generally run rather sick at high rpm on a faulty maf, this is due to the fuel mix already having been leaned out during tuning, the further leaning out will usually cause a misfire (but not always in which case it is in the lower category)
Std P1 Sti5/6 and moderately tuned (eg tek2) UK cars are most at risk in my opinion. The cars in this category don't run so lean that they misfire, they also produce enough power to quickly cause severe problems due to melting pistons and/or detonation.
I have known a new maf to fail within 2000 miles if it is not properly filtered or subject to vibration.
Personally, I wouldn't drive anything in the lower 2 categorys without some form of knock monitoring.
Andy
Std MY 99/00 UK will 'normally' quite happily survive on an under reading maf, they just go a bit faster due to the leaner mixture...lol ...and as long as you don't hold them flat out for long durations nothing untoward happens. This is due to the low state of tune and very rich mixture run on these cars as standard producing a very wide safety margin.
A highly tuned (say 340+bhp) UK/P1 or Sti will generally run rather sick at high rpm on a faulty maf, this is due to the fuel mix already having been leaned out during tuning, the further leaning out will usually cause a misfire (but not always in which case it is in the lower category)
Std P1 Sti5/6 and moderately tuned (eg tek2) UK cars are most at risk in my opinion. The cars in this category don't run so lean that they misfire, they also produce enough power to quickly cause severe problems due to melting pistons and/or detonation.
I have known a new maf to fail within 2000 miles if it is not properly filtered or subject to vibration.
Personally, I wouldn't drive anything in the lower 2 categorys without some form of knock monitoring.
Andy
28 March 2006, 08:22 PM
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Is there not an aftermarket supplier yet who can replace these unreliable MAF's with a better quality, more reliable and longer lasting MAF?
Or
Is there anyway in which the MAF can be removed i.e using a different ECU?
I'd rather spend more to solve the problem rather than just keep delaying it by buying another new one.
Craig
Or
Is there anyway in which the MAF can be removed i.e using a different ECU?
I'd rather spend more to solve the problem rather than just keep delaying it by buying another new one.
Craig
28 March 2006, 08:48 PM
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You can fit an aftermarket ECU such as Link/Gems that does not require a maf or you can fit a maf simulator conversion which does away with it on the std ecu although you would need a remap to suit.
Andy
Andy
28 March 2006, 09:22 PM
#28
Originally Posted by Andy.F
You can fit an aftermarket ECU such as Link/Gems that does not require a maf or you can fit a maf simulator conversion which does away with it on the std ecu although you would need a remap to suit.
Andy
Andy
Maz
28 March 2006, 10:06 PM
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Yes, and no !
I would normally only fit a MAFsim on a rotated mount turbo instalation where the OE MAF sensor just doesn't work well even when it's not broken !
I prefer std mount turbos to run on maf (when properly filtered and mounted) as it is more accomodating to small changes in engine spec such as exhaust mods etc.
Andy
I would normally only fit a MAFsim on a rotated mount turbo instalation where the OE MAF sensor just doesn't work well even when it's not broken !
I prefer std mount turbos to run on maf (when properly filtered and mounted) as it is more accomodating to small changes in engine spec such as exhaust mods etc.
Andy
