Leon Cupra TDI missing at low rpm
- Thread starter Spice
- Start date
Hello
No its all the time, when driving and pulling a bit harder you dont notice it, its on tick over and low throttle / rpm
Many thanks
Marcus
Mine does something like this as well..... it is especially noticeable at traffic lights when the engine is ticking over, it splutters and then idles normally, then splutters again. Also get surging/hesitation when driving at times, yet it drives fine if you thrash the arse off it or are doing steady outside lane speeds down the M-way!
Mine also failed to start this morning so it is back at a garage getting looked at... last time it cost me £200 without fixing the issue, hope they find the fault this time.
The RAC man suggested glow plugs, plus possibly an injector issue causing the lumpy running? Anyone else got any ideas?
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mikeholroyd
Guest
It won't be glow plugs -- they're only used when starting the engine, and a relay shuts them off after a few seconds after starting.
I would be inclined to think it could be a dirty fuel filter, or a tiny pinprick in a fuel line that's allowing air into the system. Even a clogged air filter can cause funny symptoms.
A few years ago I used to have a Volvo V40 diesel, and that was lumpy on idle. It turned out to be a tiny split in a pipe between the fuel filter and the injectors. The harder it was driven, the better it was and the less lumpiness is showed.
Even at Volvo prices, it was less than a tenner to fix, and a new pipe totally transformed the car.
Another thing to check is the breather on the fuel cap -- it is causing too much of a vacuum in the tank? It's worth trying a gentle drive without the fuel cap on -- with a low fuel level of course. See if running without the cap changes how the car drives.
Keep us posted
Mike
I would be inclined to think it could be a dirty fuel filter, or a tiny pinprick in a fuel line that's allowing air into the system. Even a clogged air filter can cause funny symptoms.
A few years ago I used to have a Volvo V40 diesel, and that was lumpy on idle. It turned out to be a tiny split in a pipe between the fuel filter and the injectors. The harder it was driven, the better it was and the less lumpiness is showed.
Even at Volvo prices, it was less than a tenner to fix, and a new pipe totally transformed the car.
Another thing to check is the breather on the fuel cap -- it is causing too much of a vacuum in the tank? It's worth trying a gentle drive without the fuel cap on -- with a low fuel level of course. See if running without the cap changes how the car drives.
Keep us posted
Mike
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Personally I'd kill all your fun and suggest checking the camshaft if it's a PD engine
http://www.myturbodiesel.com/1000q/multi/camshaft-inspection-replace-vw-tdi.htm
http://www.myturbodiesel.com/1000q/multi/camshaft-inspection-replace-vw-tdi.htm
This is pretty much what I thought............Although I believe my car has two issues, one being an unresolved glow plug fault that VOLKS claimed to have fixed (but failed). And a second fault somewhere that is causing the rough running and other issues I described.
The garages I have tried so far don't seem to be able to get beyond reading the bloody fault codes!!
No one seems actually able to diagnose the actual issue as the computer isn't giving them the answer!
I hope the garage the car is with now can get it sorted as they appear to know what they were talking about........ if they resolve the issue I will obviously post an update.
To the previous poster, I don't think it is a camshaft issue, my car sounds nothing like the one in the video link and it has had main dealer FSH, so correct oil all along?
Well I hope it isn't that anyway!
I honestly think the issue is related to fuelling somehow or maybe an small airleak somewhere. Hopefully the garage will provide answers tomorrow.
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