Potential Turbo Issue

L

louisc3uk1

Member
Hi all

This is my first ever post on here so go easy on me! Before I start I'd just like to say that it's brilliant that so many people interact one here and provide others (idiots like me) with great information. I own an 54 plate 1.4TDI A2 Sport (75), my brother bought it from new and I purchased it from him a few years back, it's never had a problem that I'm aware of and has always been regularly serviced, of late by myself as I intend to keep the car for as long as he lasts.

However, the first issue has arisen. Last Friday (9 days ago) I first experienced some power issues whilst popping out, towards the top end of the revs the car was hesitant and jerking slightly, the rev counter would almost jam then surge forward a little. I experienced the issue a few more times through the week and on Friday (which is my day off) I came onto this forum and started doing some research. The multiple threads which I read suggested the issue would likely be a damaged pipe from the intercooler or the intercooler itself leading to pressure loss. I took my dad for a spin up the local dual carriage way to show him the problem and as the car hit 3k ish revs, under some pressure the engine died and wouldn't restart. I took the opportunity to call the AA (as I don't have home start) to try and get their opinion, that ended in the engineer agreeing with my diagnosis. He plugged his computer in and it showed no faults, however he said he rebooted the car and it did restart leading me to be able to drive home.

I went out today to have a real look at the car, I'm not a mechanic by any means but my dad has a couple of kit cars with Cosworth lumps in so an little idea. None of the intercooler pipes appear to be split but I did notice that the main pipe that joins the turbo, the pipe that comes from above, has a large oil build up on the exterior. I'd read on posts to look for oil build ups around the back of the engine bay, having read the post "One hell of an oil leak". I ended up removing both the air pipes that attach to the the turbo, initially to check the spindle in the turbo, my dad said that if there was a lot of play in it the bearings had most likely gone. Although the spindle seems fine (no play and spins) I did notice that the intercooler pipes had oil inside them, there was literally oil everywhere.

At this point I came back in the do some more reading, suspecting that the turbo has leaked internally thus causing the oil to leak out into the intercooler pipe. I've had a look online and seen that a refurb turbo on an exchange basis is £200, not ideal but ultimately not the end of the world. I must admit that I neglected looking at the intercooler itself as I was more interested in chasing the oil leakage. Through trawling the forums and reading old posts I can see that the intercooler could actually be the issue, so......... moving onto my actual question.

1. If the intercooler had split or been damaged, would that cause oil to be in the intercooler pipes? - specifically the 2 pipes between the turbo and cooler, I haven't yet checked the pipe that runs along the top and goes into the top right of the engine.

2. Does it sound like the turbo is knackered??

I'm thinking it's a turbo issue as I'm not sure where else the oil would be coming from. I will be back out there tomorrow afternoon to check the intercooler, I spose I'll have to take it out to have a proper good look.

I will also take some pictures and upload them to try and provide a better picture for anyone who may be able to help.

I apologise in advance in any of my car jargon isn't up to scratch, I love cars and tinkering with them but haven't got worlds of expericence.

Any help, no matter how big or small would be greatly appreciated, I'm a student Primary school teacher and could do without a huge garage bill. Thanks so much!!!
 
Some oil in the intercooler pipes is quite normal, how much is acceptable is somewhat open to interpretation.
The A2's turbo in the TDI75 is considered somewhat bullet proof, so even though it may be leaking some oil into the intercooler pipes I think it is unlikely to be the cause of your lack of power issues.
I blown intercooler is much more likely, look at the bottom of the intercooler where the aluminium stack and the black plastic end cap mate, there is a rubber seal in there which is likely to have partial failed
 
Hi

Welcome, no need to apologise that was a really excellent first post, but sorry I can't help, my A2 drinks petrol. - Andy
 
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Great to read such an informative thread, I'd love to be able to offer assistance though I'm sure someone will be here soon to help. Depronman already suggested a likely offender, keep us posted.
 
Thanks to everyone that took the time to reply. I've been back out at it this afternoon and sadly still haven't found the problem.

Replying to depronman - "I blown intercooler is much more likely, look at the bottom of the intercooler where the aluminium stack and the black plastic end cap mate, there is a rubber seal in there which is likely to have partial failed"

I really hoped you were right and went out earlier full of enthusiasm thinking the intercooler was going to be the suspect. I took the last piece of pipe off the bottom of the intercooler (a short angled piece) to get a look at the plastic end. I couldn't find the rubber seal you mentioned anywhere, although I haven't taken to intercooler off the car there's no visible damage. As I was inspecting the intercooler my dad popped into the garage and pulled out a self constructed tool he'd made for testing for air leaks (I aim to somehow attach a photo of this). Anyway, we rigged his home-made device up and passed air through the intercooler and surrounding pipes, at no point could we hear any hissing or leaking, infant the air pressure would build up, to us this suggests the system is air tight and has no damage or leaks.

Have I totally misunderstood what you were saying depronman? The pipe fits over the plastic end of the intercooler and is secured with a jubilee clip, we saw no ring anywhere. I feel like I wasn't able to identify what you said and maybe I've overlooked it, although... if there was a failed rubber seal somewhere surely our pressure test would have picked it up?

What happened next....

I decided it was time to reassemble the car and see if the magic A2 fairy and blessed my car during the night. So I did just that, I took her for a spin round the block and although I would say she's defiantly running better I could still feel the surges/delays in power around 3.5k revs. One thing to note, yesterday when in neutral just sitting still there car would not rev past 3k, it would simply just hold there, maybe rev a little past 3k then die off. Today, in neutral she's raving back to 4.5k revs.

I spose I'm at a bit of a loss now, assuming the turbo is bulletproof, with no leaks in the pipes and the intercooler seemingly intact what could it be?

Is it time to seek professional help? I live in Chigwell, London/Essex border. Can anyone recommend somewhere to take it that are competent with A2's?

Also, is it ok to keep using the car? I need to get to school this week, do you think I'll do further damage driving it or as long as I take it easy it should be ok?

I've attached some pictures, I wish I had taken more now but in the moment I tend to forget.

Pic 1 - My dads homemade device, its actually meant to connect to the compressor but we were just using a bike pump today. (just thought it was cool and you guys may like it)

Pic 2 - The metal pipe that rubs parallel with the engine from the intercooler, some oil is present there too.

Pic 3 - Where the intercooler pipe meets the engine on the top right hadn't side, looks ok to me!

Thanks all again!!
 

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I just want to add something here, might be totally wrong but its worth a try.
My lads A2,54 plate 1.4TDI was virtually doing the same and we suspected the turbo but the lads father in law suggested we take a look at the fuel filter.. so we did and it was gunked up with black residue so I took off the filter from a scrapper I have and put that in...........after a bit off white smoke and then a good run, the car drove fine and has done so now for the last 4 weeks or so. If you manage to snap the screw on the filter housing Depronman can supply a better than original replacement

here is the thread about the lads car.

https://www.a2oc.net/community/index.php?threads/tdi-lacking-power.34446/
 
Thanks Johnyfartbox and AndyP, I've got nothing else to go on and after reading that thread it does seem like a viable option. So... do I need one of these custom made screws before I attempt to replace the fuel filter? Shall I drop depronman a pm>?
 
I changed mine recently without breaking the screw, generally I think doing it back up is the greater risk, so finger tight only (really!).
A fuel filter from your local motor factor is not too expensive, so you don't have much to lose.
 
As you have now ruled out the intercooler (the seal is an O ring that sits between the black plastic end of the intercooler and the aluminium intercooler body) if you can't see the seal then it is likely that all is good on the intercooler side
So, with a diesel engine if the air system is all good then the problem is likely to be fuel starvation, your symptoms are aligned with lack of fuel particularly at higher revs where fuel demand is the greatest.
The fuel filter on the later TDI's as a very keep spot, this being the drain water screw, this screw must be removed to remove the end of the filter housing to change the paper element, it is highly likely to break. This is where my replacement screw comes in to its own
The alternative is to replace the entire fuel filter housing at about 3 times the price of my screw.

I suspect that your filter will be caked in black goo, replace the filter element, clean out all the goo and let a little diesel flow through the pipe from tank to filter housing to flush out any remaining goo.
Replace the filter element and fuel filter end cap and drain screw, crank the engine and hopefully it will fire up once fuel is pulled through
Take it for a run and keep your fingers crossed :)

A good dose of 'liquid moli' purge would also be advised to clean the injectors and fuel lines

Cheers,
Paul
 
I experienced something similar at around 100K miles. In my case it was a failure of the harness that connects to the injectors under the cam cover. Car stopped, or went into limp home mode, park up reboot, ran fine for a while.

My car did display a fault though, an injector failure to be corrected at enormous cost. I gambled on the harness (circa £70) and the car has been fine since. Just a thought and possibly not in your case as there was no error.

Going for the fuel filter is a good suggestion, a logical cause and cheap. The filter could have cleared enough fuel while waiting for the AA and the reboot could be a complete red-herring.

After replacing a fuel filter your car may be a complete pig to start.
 
Ok guys, yet again a massive thanks to those who've taken the time to reply.

It will be a few days before I get the opportunity to even think about fixing the car now, I've read some related threads around the fuel filter now and I'm hopeful this will cure the issue.

One question though... (I'm not sure if this will become obvious once I see the fuel filter but I'd rather ask now)

Do you have to unscrew the drain screw first? or the actual cap fitting then once you have it out of the housing you undo the drain screw to release the paper filter?

Thanks
 
You have to unscrew the drain first because the flange on the drain bolt covers the hex of the main case bolt. Unless you trim it a bit first with a dremel or something.
 
AndyP said:
You have to unscrew the drain first because the flange on the drain bolt covers the hex of the main case bolt. Unless you trim it a bit first with a dremel or something.
Click to expand...

If you were to trim it to allow access to the hex bolt, would you still have to undo it later to change the paper filter bit? Or could you get away with not undoing the drain pipe at all?
 
No, I think you could leave the drain screw in place. It would make a bit more mess removing the main body of the filter though.
 
My advice would be to try the drain screw, if it has been torqued correctly it will come loose and allow controlled drainage into a suitable container. It would still be advisable to have a drip tray underneath. If you don't think it will come loose get yourself a big drip tray and go with the advice above. If you are working on axle stands work at arms length and make sure you can get out / away quickly if you are not one for getting messed up.

One final note I lightly clamp three pipes, can't advise which but it can be worked out under the car. Minimises loss of fuel and makes the car much. much easier to start. May be worth considering as you are doing diagnostic work and may need thinking time. I'm sure an expert will comment if I've not quite got this right.

Edit: My heat-shields are off at the moment for a handbrake cable replacement so snapped you a picture. Above a heat-shield just ahead of the N/S rear wheel:

no5tkEe.jpg
 
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philward said:
My advice would be to try the drain screw, if it has been torqued correctly it will come loose and allow controlled drainage into a suitable container. It would still be advisable to have a drip tray underneath. If you don't think it will come loose get yourself a big drip tray and go with the advice above. If you are working on axle stands work at arms length and make sure you can get out / away quickly if you are not one for getting messed up.

One final note I lightly clamp three pipes, can't advise which but it can be worked out under the car. Minimises loss of fuel and makes the car much. much easier to start. May be worth considering as you are doing diagnostic work and may need thinking time. I'm sure an expert will comment if I've not quite got this right.

Edit: My heat-shields are off at the moment for a handbrake cable replacement so snapped you a picture. Above a heat-shield just ahead of the N/S rear wheel:

no5tkEe.jpg
Click to expand...

The reason for the screw being there is mainly to allow water to be drained from the fuel system periodically. It is a biproduct of the screw that you can use it to drain the fuel when doing a filter change. Hence the design of the screw with a large flange that covers the hex nut in the housing end cap
Cheers. Paul


Sent from my iPhone using Tapatalk
 
Hi all

A bit of a turn of events this evening, I can say (very happily) that the fuel filter appears to have fixed the problem!

I stopped in at europarts on the way to work to pick up a fuel filter, when I got home I didn't intend on actually doing the job but I wanted to have a look at the filter housing/flange myself so I knew what I was in for over the weekend. Long story short, I was looking to see if I could find a tool in my dads garage to get under the flange and spin the plastic nut on the cap. I had my neighbour in the garage with me and I hadn't bothered to explain how the drain nut was quite 'delicate', anyway... I had just found a lovely adjustable spanner which I thought may do the job but in the time I'd been looking, my neighbour got under the car and just undone the drain nut! He was like "I'm not sure what all the fuss is about, I just undone it with a 10mm socket", hahah...., luckily it didn't break and we can be sure that ignorance was bliss on that occasion. So we ended up swapping the filters over there and then.

The car fired back up straight away but cut out after about 10 seconds, it took a few long cranks to get it to boot up again. Big puffs of black smoke at first, then followed by white smoke chugged out of the exhaust but the car began to rev all the way to the red line again. I took it out and booted it up and down the duel carriage way, she pulled lovely through the first 3 gears (then I ran out of road). In hindsight I think I've had power loss for quite a while but because it was fairly subtle (no jerking) I hadn't realised, I drive quite slowly anyway.

I can't believe it was such a simple problem and job after such complex inspections of the intercooler and surrounding pipes, there was a moment on Sunday when I looked over my shoulder and thought... I'm a school teacher not a mechanic, wtf am I doing, is this really going to work ever again lol!!

Thank you so much to all the people who wrote on my thread, as I said before I really think this website community is awesome. I hope others read this post in the future and it helps them to solve issues on their A2's.

I'm going to pop up another couple of posts over the weekend in regards to a spare key issue and a recommendation on someone to sop my cam belt change.

Thanks again, Louis.

P.S - I've attached a photo of the old fuel filter.
28741581_10155655975408409_1769509735_n.jpg
 
Lesson learned and glad it worked :)................As you read in my thread about my lads car....we were convinced it was the turbo or something sinister but I suppose we all at some point think the worst case scenario just like we did. Chuck some redex or similar in the tank on your next fill up, wont do no harm and if you shop around you can get it for two quid a bottle.
 
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