hi
i have a 110 bhp 1.9tdi 1996. being my first diesel i wasn't really sure on how quick it would be so didn't really think nothing of it when i'm getting top speed of 85-90mph and takes an eternity to get there unless going down a hill. really poor acceleration is standard and if i'm cruising on the motorway and hit a big hill i cannot sustain my speed.
anyway i thought an ecu remap was in order, i had this done and had no real significant gains apart from possibly a tiny bit quicker off the mark. the guy that mapped it was really good and spent 2 hours of his own time with me. he was confused why the map made no difference but on driving it he said that i'm driving the car without a turbo and it should be much quicker as standard without the map.
i was told that a new maf filter was put on the car by the previous owner less than 2 weeks prior (i had receipt) so his attention went to the turbo. he took off the actuator and shortened the bar, he was not an audi specialist but didn't think the actuator should be floppy and there should be pressure on the bar. on refitting again no improvement but as he listened to the engine he was sure there is nothing wrong with the turbo but it doesn't seem to be kicking in fully. i left there with the advise that i need a new actuator.
on returning home i decided to unplug the maf to see what difference it made and it hardly made any!
i'm no expert but if i unplug the maf shouldnt there be a noticable difference in performance? if this is the case then perhaps i didn't have a new maf after all and this is faulty and causing the power problem? can anyone fill me in or advise as i need to unleash the beast!
cheers
i have a 110 bhp 1.9tdi 1996. being my first diesel i wasn't really sure on how quick it would be so didn't really think nothing of it when i'm getting top speed of 85-90mph and takes an eternity to get there unless going down a hill. really poor acceleration is standard and if i'm cruising on the motorway and hit a big hill i cannot sustain my speed.
anyway i thought an ecu remap was in order, i had this done and had no real significant gains apart from possibly a tiny bit quicker off the mark. the guy that mapped it was really good and spent 2 hours of his own time with me. he was confused why the map made no difference but on driving it he said that i'm driving the car without a turbo and it should be much quicker as standard without the map.
i was told that a new maf filter was put on the car by the previous owner less than 2 weeks prior (i had receipt) so his attention went to the turbo. he took off the actuator and shortened the bar, he was not an audi specialist but didn't think the actuator should be floppy and there should be pressure on the bar. on refitting again no improvement but as he listened to the engine he was sure there is nothing wrong with the turbo but it doesn't seem to be kicking in fully. i left there with the advise that i need a new actuator.
on returning home i decided to unplug the maf to see what difference it made and it hardly made any!
i'm no expert but if i unplug the maf shouldnt there be a noticable difference in performance? if this is the case then perhaps i didn't have a new maf after all and this is faulty and causing the power problem? can anyone fill me in or advise as i need to unleash the beast!
cheers
Site Moderator
I'm not sure what a maf filter is, but you should first look for any rotted or disconnected vacuum and boost lines lines.
sorry i think what we in the UK call a mass air flow filter (maf) in th US you call it an air mass filter????? i was told that this could be my problem but not so sure now........
i checked for any rotted hoses and couldn't find any. i noticed that the diapham bar on the turbo actuator does not move when the engine is revved.
any ideas what could cause this other than a fualty actuator?
thanks
i checked for any rotted hoses and couldn't find any. i noticed that the diapham bar on the turbo actuator does not move when the engine is revved.
any ideas what could cause this other than a fualty actuator?
thanks
Site Moderator
I'm not at all faminliar with the tdi's since they didn't import them to the US, but I'll give it a shot.
When the previous owner changed the maf, did they use a different part than stock? You may also want to check the N75 valve. The wastegate actuator will not move when revving the engine because the turbo isn't making any boost. Do you have a boost gauge installed?
When the previous owner changed the maf, did they use a different part than stock? You may also want to check the N75 valve. The wastegate actuator will not move when revving the engine because the turbo isn't making any boost. Do you have a boost gauge installed?
no i don't have a boost gauge installed.
i'm not sure that the supposingly new maf is an audi part, i bought the car from a trader who said his mechanic done it. i wouldn't be suprised if this didn't happen though.
i was told that the bar on the actuator if working would move while revving, it goes to show you can't believe everything you hear. where is the n75 valve?
will vag-com scan help to locate where the fault is?
thanks
i'm not sure that the supposingly new maf is an audi part, i bought the car from a trader who said his mechanic done it. i wouldn't be suprised if this didn't happen though.
i was told that the bar on the actuator if working would move while revving, it goes to show you can't believe everything you hear. where is the n75 valve?
will vag-com scan help to locate where the fault is?
thanks
Site Moderator
The VAG will help you find any codes the ECU has. If you have one or have access to one, get it scanned for codes. There's also a function in the vag-com that will let you view the boost.
Here's a picture of one installed- pic
It's the piece in the middle of the picture with the 3 hose claps connected to it. If you have one, it will be located on the intake pipe with 2 vacuum lines going to the turbo and wastegate. I'm not entirely sure if yours has it, but it will have some kind of boost controller.
Here's a picture of one installed- pic
It's the piece in the middle of the picture with the 3 hose claps connected to it. If you have one, it will be located on the intake pipe with 2 vacuum lines going to the turbo and wastegate. I'm not entirely sure if yours has it, but it will have some kind of boost controller.
i have something which i suspect is the n75, basically it is the next part in line from the silicone hose from the top of the actuator. would that be it?
i had a scan done, do you still think the same fault?
01265 exhaust gas recirc valve - open or short to ground
00575 intake manifold pressure - control difference intermittant
00553 mass air flow (g70) - open or short to ground
where would you go from here?
cheers
i had a scan done, do you still think the same fault?
01265 exhaust gas recirc valve - open or short to ground
00575 intake manifold pressure - control difference intermittant
00553 mass air flow (g70) - open or short to ground
where would you go from here?
cheers
i just found this diagram that may help me fix this.... http://pics2.tdiclub.com/members/sch...uum_all_01.jpg
i'm guessing the problem is with either the n18, n70 or the actuator
anyone know how i can test these for faults or should i be looking elsewhere? my vag com says open or short to ground, is this a good indication that the unit is faulty or a bad connection?
thanks
i'm guessing the problem is with either the n18, n70 or the actuator
anyone know how i can test these for faults or should i be looking elsewhere? my vag com says open or short to ground, is this a good indication that the unit is faulty or a bad connection?
thanks