jamieg Posted November 21, 2008 Report Share Posted November 21, 2008 (edited) Had my car in a garage today and been advised following a lambda replacement that if this does not cure the MAP sensor is most likely the fault if not then the ECU, I've had a look in my haynes manual and I can't find any reference to the MAP sensor, is there one on an AJQ engine also where is it? Also am I correct in saying that the Inlet Air Temperature Sensor only works when the car is cold therefore if I've got a problem when the car is warm then it's nothing to do with the IAT sensor. Thanks in advance "yet again and again, should have sold the car quick - lol - no chance love it!" Car is an A3 1.8T Quattro Sport AJQ Engine - Year 2000 (X) Edited November 21, 2008 by jamieg adding details Link to comment Share on other sites More sharing options...
steve2 Posted November 21, 2008 Report Share Posted November 21, 2008 try looking for a MAF sensor I cleaned mine with a can of electrical contact cleaner and it worked fine do a search on here for MAF Link to comment Share on other sites More sharing options...
jamieg Posted November 21, 2008 Author Report Share Posted November 21, 2008 Cheers for the reply - the MAF is 12months old or just over with a bosch part, not getting any errors from VAG COM either, would be really really surprised if it was MAF related. Link to comment Share on other sites More sharing options...
shark_90 Posted November 21, 2008 Report Share Posted November 21, 2008 The MAP sensor measures boost pressure etc.. who has told you that it would be that? What is the problem? Link to comment Share on other sites More sharing options...
jamieg Posted November 22, 2008 Author Report Share Posted November 22, 2008 A local garage I use, they are pretty good and have a good rep. Problems I'm having is the car is running very rich, when pulling away pre turbo there is a bit of hesitation, if I'm booting up a hill I get a stutter at around 2200 rpm and also around 2800 then off it goes, the MPG's just now are really really poor for my car and driving style, it's down 8mpg from normal, when pulling up I dip the clutch and the revs drop to 500 and shoot back to 700-800, now and again the revs just shoot up to around 1500 rpm for no reason after pulling up, I've had a few things done to the car to help with this. Coolant Temp Sensor Lambda - following errors reported via vag com DV coil packs Link to comment Share on other sites More sharing options...
Mook Posted November 22, 2008 Report Share Posted November 22, 2008 I'd say it's very unlikely to be the MAP sensor. The problem with MAF sensors are that they don't always report back to the ECU that there's a problem. I would look to replace the MAF again first, then try again. Also, have you checked there are no air leaks - this will cause the car to run lean and the ECU will try to over-compensate with fuelling as the anti-knock sensors get their knickers in a twist. Air leaks will also affect the ability for the car to pull under load. Link to comment Share on other sites More sharing options...
shark_90 Posted November 22, 2008 Report Share Posted November 22, 2008 I really don't think your MAP sensor is anything to do with it. Definitely sounds like an air leak to me but I think I've posted that before in relation to your problems. Link to comment Share on other sites More sharing options...
jamieg Posted November 22, 2008 Author Report Share Posted November 22, 2008 Cheers guys - the garage also checked over the engine for air leaks yesterday, plus did the spraying of some liquid over the engine trick to check also, what a bugger if its the MAF again! Link to comment Share on other sites More sharing options...
jamieg Posted November 22, 2008 Author Report Share Posted November 22, 2008 Gents - I ran the car recently like in the last two months with the MAF unplugged and the car was exactly the same, no changes to the above - I've also read on here thats a sure fire way of testing if the MAF has gone, disconnect and run the car if problem goes away then it's the MAF? Link to comment Share on other sites More sharing options...
Mook Posted November 22, 2008 Report Share Posted November 22, 2008 Yes, that test is correct - unplug and if it runs the same, it's generally not the MAF. Without seeing or hearing it, it's getting tricky to diagnose over t'Internet Link to comment Share on other sites More sharing options...
jamieg Posted November 22, 2008 Author Report Share Posted November 22, 2008 I've ran the car without MAF for about 30 miles today, i've not had the revving issue for those miles but the car is still dipping with the rev's upon pulling up at traffic lights and junctions etc.. hmmm any thoughts or is it back to a garage to rip me orf not had a chance to test the uphill and hesitation but that does not appear to be there for the little running I've given it, these miles were split therefore the engine would have been cold for around 10-15 of these miles. Link to comment Share on other sites More sharing options...
Mook Posted November 23, 2008 Report Share Posted November 23, 2008 You need to find a reputable independent Audi specialist - not all garages are there to rip you off. Without seeing the car, it's not possible to diagnose it remotely. Link to comment Share on other sites More sharing options...
Coopra Posted December 1, 2008 Report Share Posted December 1, 2008 (edited) Hi, did you get sorted? I had a similar problem with my 2004 Ibiza Cupra 20VT. Changed all the things you have changed and it still ran very badly. I eventually got it vag commed and it turned out to be the MAP sensor, the fault code was G31 manifold pressure/ boost sensor. One of the wires has snapped so the ECU had no idea how much pressure was in the manifold, as soon as it came on boost it would just lurch forward and was down on power. The MAP sensor on the my engine (BBU, same as an AUQ) is on the inlet pipe into the manifold, on mine its situated just under the headlight. Edited December 1, 2008 by Coopra Link to comment Share on other sites More sharing options...
Mook Posted December 2, 2008 Report Share Posted December 2, 2008 Thanks for that Coopra and welcome to Tyresmoke Link to comment Share on other sites More sharing options...
jamieg Posted December 2, 2008 Author Report Share Posted December 2, 2008 Cheers for the info, it's always good to move forward, I've got no VAG COM errors at all. The motor is booked in to an audi specialist tomorrow to get to the bottom of the issues, I would love to get it sorted without putting it in the garage but I don't think it's going to happen. I can't even find any reference to the MAP sensor in the Haynes manual or ElsaWin and can't find it on my AJQ engine, I'm still along the lines of a VAC leak somewhere but can't find anything, as said on other posts the car is fine under idle reving through there is nothing but under loads i.e. with the car moving the problem become apparent. Someone at the local garage advised it could be the MAP but others who have not seen the car say its very unlikley the be the MAP. Link to comment Share on other sites More sharing options...
jamieg Posted January 21, 2009 Author Report Share Posted January 21, 2009 Still no joy on this one, an audi specialist had a look for the day but really only spent an hour working on the car which I found out, they found a pipe they said was compressing under load which went from crank case to manifold, I've replaced this item however no change to the problem. any thoughts people? Link to comment Share on other sites More sharing options...
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