kr3 Posted October 13, 2010 Share Posted October 13, 2010 Hi, my old man needs some help with his 04 td5. It starts ok, ticks over and revs at standstill ok. Occasionally when you try to move off ther is no power or very little, but then it gets power and shoots off! Had turbo changed and various other parts, main dealer cant sort it. Any help would be great, thanks. Quote Link to comment Share on other sites More sharing options...
SiWhite Posted October 13, 2010 Share Posted October 13, 2010 Get it on a Nanocom or similar - find a local independent garage to help, and avoid the dealer. Could be any number of issues - it would be silly to guess at a possible component failure without having read the fault codes. Quote Link to comment Share on other sites More sharing options...
K88 MUD Posted October 14, 2010 Share Posted October 14, 2010 Stick your location up and someone close might be able to help you. Quote Link to comment Share on other sites More sharing options...
landy andy. Posted October 14, 2010 Share Posted October 14, 2010 It is the MAF failed, if you disconnect it will be better, and only replace with Land Rover part, not copy. Andy Quote Link to comment Share on other sites More sharing options...
Gromit Posted October 14, 2010 Share Posted October 14, 2010 Hi, my old man needs some help with his 04 td5. It starts ok, ticks over and revs at standstill ok. Occasionally when you try to move off ther is no power or very little, but then it gets power and shoots off! Had turbo changed and various other parts, main dealer cant sort it. Any help would be great, thanks. Hi, mine does exactly the same thing, very occasionally, around once a week or so, at first start. Too little to diagnose at the moment. Was the waste gate actuator changed with the turbo? (Is this a defender unit? The disco unit has an extra modulator thingy on the wategate) If the waste gate sticks, you get an overboost error code, and the engine goes into limp home mode. Agree with above, disconnect the MAF sensor and see what happens. Does it have EGR? This is controlled by the MAP sensor - if duff, the EGR could be sticking (worth removing the EGR altogether) Quote Link to comment Share on other sites More sharing options...
kr3 Posted October 16, 2010 Author Share Posted October 16, 2010 Thanks for the advice, its a defender by the way. Disconnected MAF and doesnt do it anymore, just a bit flat now. Had new pump, turbo fitted at Armstrong Massey in Beverley but didnt cure it and still had to pay! Getting another MAF around £100 so hope thats it! Quote Link to comment Share on other sites More sharing options...
101sean Posted October 16, 2010 Share Posted October 16, 2010 Typical dealer, throw bits at it until it's cured rather than diagnosing the problem, poor old punter pays. Dodgy MAF doesn't show as a fault, you have to look at flow rates or, as most of us know, just unplug it! My brother in law's IAT/IAP sensor also give similar symptoms when it got really mucky from the intercooler not being cleaned out Local dealer to me wanted change a 10AS alarm after having it on test all day, all that was wrong was a 10p fuse. Quote Link to comment Share on other sites More sharing options...
kr3 Posted October 19, 2010 Author Share Posted October 19, 2010 Fitted a new MAF today, Problem solved!How easy, but why couldnt a dealer or "specialist" work that out? Thanks for the help. Quote Link to comment Share on other sites More sharing options...
gazelle Posted October 19, 2010 Share Posted October 19, 2010 Fitted a new MAF today, Problem solved!How easy, but why couldnt a dealer or "specialist" work that out? Thanks for the help. Doesn't come up on diagnostics - requires application of experience and common sense......... Can't think really.... The Daily Telegraph's Honest John is always commenting on the fact that experienced staff tend to leave the dealers to set up on their own. Hence the lack of experience in the dealers. Quote Link to comment Share on other sites More sharing options...
tinweasel Posted October 20, 2010 Share Posted October 20, 2010 ok silly question time, where is this MAF? as mine is doing this and I was told its normal, might be worth a try Quote Link to comment Share on other sites More sharing options...
Porny Posted October 21, 2010 Share Posted October 21, 2010 Doesn't come up on diagnostics - requires application of experience and common sense......... Can't think really.... It does come up on the diagnostics - you've just got to know what you are looking for. Just looking at the Fault Codes is only part of using diagnostics. A Td5 MAF sensor typically fails in two ways - 1) It goes dead completely and returns a value of 0kg/hr to the ECU. The ECU logs this as fault, and adds it to the fault code list. 2) The more common way a MAF fails is to return a value of 4 kg/hr to the ECU. Because it's not 0 kg/hr, the ECU does not see it as a fault - so it does not add anything to the fault code list. This is where most dealers and quite a few independants seem to fall down. You need to check the live date values - with the engine running. If at idle you see 4kg/hr your MAF is dead (and the one effect is the poor starting and lack of throttle response as mentioned). At idle a MAF should read betweem 52 and 60 Kg/hr (depends if you have a genuine part MAF or a cheap copy). There is a 3rd common failure mode I see quite often, which is worse with cheap copy MAF sensors... When you out driving you should see 525 + Kg/hr (standard, not remapped) when under load and making it rev a bit. I've seen quite a few MAF sensors max out at between 250 and 400 Kg/hr - which results in a very flat TD5 as the MAF sensor is telling the engine it's not seeing that much air, so the ECU matches air flow to the fuelling. The other issue is 'failing' MAF sensors, which at idle give a value of 20 - 30 Kg/hr at idle - again the lower air flow value results in poor low end performance, but the off set from what it should be at idle gets multiplied at top end, so the max air flow the MAF believes it is seeing is actually lower than it should be - again affecting performance. The MAF (Mass Air Flow) sensor is located at the clean out outlet side of the air filter... and is connected to the pipe that goes down to the inlet of the turbo. Ian Quote Link to comment Share on other sites More sharing options...
Anderzander Posted October 21, 2010 Share Posted October 21, 2010 Brilliant post Ian - thank you. A good one for the tech archive. Quote Link to comment Share on other sites More sharing options...
gazelle Posted October 21, 2010 Share Posted October 21, 2010 Well, thank you for putting me right on this one, Ian. We learn something new every day! Cheers! Martin Quote Link to comment Share on other sites More sharing options...
Gromit Posted October 22, 2010 Share Posted October 22, 2010 Brilliant post Ian - thank you. A good one for the tech archive. Seconded. It would be great to collect the combined info on the TD5 sensors somewhere. Quote Link to comment Share on other sites More sharing options...
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