Hi all. I am aware there are many current and old threads relating to limp mode related problems but my TDI90 is now displaying slightly different symptoms. I thought better to start another chat rather than hijack/resurrect somebody else's.
The car is a well cared for 2004 TDI90 on 140K. I've had it for a couple of years and done about 24K trouble free miles.
The other relevant bit of back story on the car (as we'll definitely wander into turbo talk) would be that the car had a brand new factory fresh turbo fitted at 83K along with extensive engine work costing a previous owner nearly £2400.00 in parts and labour so there's really only about 57,000 miles on the current turbo.
I have to say it has always driven really nicely with great power delivery until it started having 'limp mode' problems last year...
To start with it was just the usual story - if going up hill or accelerating hard for prolonged periods of time it would lose power and the engine light would come on. Switching off the engine and starting would immediately resolve the problem, although the engine light would usually stay on for a bit longer. I had a bit of a look around the hoses and pipework last year and considered that the intercooler was a possible source of the problem as it was slightly oily at the bottom but not too bad, but it was still driving really well most of the time so I left it.
I have a new intercooler and I'm planning on fitting that next weekend all being well, at which point I'll get a better look at hoses etc.
The bit where this is different to most is on the way back from MOT last week, I gave it a really good blast on flat roads and the engine light came on and went into limp mode... but it never went off . It's been parked up for a week almost and I can't get the light to go out, and the turbo's permanently disabled - the car is obviously picking up a problem as soon as the key is turned as the light is off for maybe half a second on start up and then comes on and stays on.
I disconnected the MAF this morning and went for a drive, and did a few cycles of starting and switching off the car but that hasn't had any effect.
What are the likely causes of the engine light on start up, would it be possible to have a big enough air leak that the engine management senses this immediately? - maybe absolutely booting it last week finished something off that was causing my more common limp mode issues, or damaged something.
I've read another possible problem could be with N75 valve - is that a likely culprit for triggering a permanent engine fault?
Is there a guide/s that help illustrate the removal of components to better access the turbo and pipes? - it's not easy getting a view of this side of the engine!
The current state of play is that the car is up on axle stands with covers and undertray removed ready for me tackling the intercooler change next week. Is there anything else I should perhaps be looking at?
Kennedy
The car is a well cared for 2004 TDI90 on 140K. I've had it for a couple of years and done about 24K trouble free miles.
The other relevant bit of back story on the car (as we'll definitely wander into turbo talk) would be that the car had a brand new factory fresh turbo fitted at 83K along with extensive engine work costing a previous owner nearly £2400.00 in parts and labour so there's really only about 57,000 miles on the current turbo.
I have to say it has always driven really nicely with great power delivery until it started having 'limp mode' problems last year...
To start with it was just the usual story - if going up hill or accelerating hard for prolonged periods of time it would lose power and the engine light would come on. Switching off the engine and starting would immediately resolve the problem, although the engine light would usually stay on for a bit longer. I had a bit of a look around the hoses and pipework last year and considered that the intercooler was a possible source of the problem as it was slightly oily at the bottom but not too bad, but it was still driving really well most of the time so I left it.
I have a new intercooler and I'm planning on fitting that next weekend all being well, at which point I'll get a better look at hoses etc.
The bit where this is different to most is on the way back from MOT last week, I gave it a really good blast on flat roads and the engine light came on and went into limp mode... but it never went off . It's been parked up for a week almost and I can't get the light to go out, and the turbo's permanently disabled - the car is obviously picking up a problem as soon as the key is turned as the light is off for maybe half a second on start up and then comes on and stays on.
I disconnected the MAF this morning and went for a drive, and did a few cycles of starting and switching off the car but that hasn't had any effect.
What are the likely causes of the engine light on start up, would it be possible to have a big enough air leak that the engine management senses this immediately? - maybe absolutely booting it last week finished something off that was causing my more common limp mode issues, or damaged something.
I've read another possible problem could be with N75 valve - is that a likely culprit for triggering a permanent engine fault?
Is there a guide/s that help illustrate the removal of components to better access the turbo and pipes? - it's not easy getting a view of this side of the engine!
The current state of play is that the car is up on axle stands with covers and undertray removed ready for me tackling the intercooler change next week. Is there anything else I should perhaps be looking at?
Kennedy
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