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Strange engine problem (TT related) Clever People Required!



Pep

ClioSport Club Member
  M2,XJS,S1000RR
Right then, need some help/answers if possible.
Fit girl at work has a 10 plate TT petrol Turbo on 44k and we think it's fooked. Wednesday morning she pulled up at work and it was running fine, just like normal, she comes to leave and the car won't start at all. It turns over and the starter motor spins but nothing at all. Checked some of the usual simple suspects and nothing changed at all.

Local garage we know had it in today for a quick look and initially thought it was the timing chain snapped, which I know wouldn't be the case! Long story short they have done a compression test on it and all 4 cylinders have 0 pressure, so all of the air is getting out somewhere. I'm thinking that it could be the tensioner failed, bent the valves slightly and they now aren't sitting right?

I can't see it being cracked pistons, rings gone, or a hole in the block covering 4 cylinders.

So we're a bit stumped until the rocker cover comes off, and I'm ridiculously interested since it's a bit of a weird one!

Anyone help?!

No pictures I'm afraid, would be weird.
@Chip-mk1
@Gray - meant to ask you earlier but forgot!!
 
  PB172,dci100,dci65
Just an idea:
IF there is no compresion, you can push the car really easy even in gear. Was it measured correctly?
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
Just an idea:
IF there is no compresion, you can push the car really easy even in gear. Was it measured correctly?

I did think that, but apparently they compression tested 2 other cars to make sure their gear was fine and they came up as expected. They are a good garage to be fair so I don't think they'd be missing obvious stuff or misusing stuff.

leakdown test

Whats one of those dude?
 
  dan's cast offs.
pressurise each cylinder one at a time, if you've genuinely got no compression you'll hear air escaping when you start.
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
Is that a pretty standard thing to do?
From what they've said theres literally no way of even getting any pressure in to hear it escaping, but I did hear second hand from my boss. But we've both got a good idea of how engines work.

Just seems very strange how it was running perfectly at 8am, and wouldn't start at 4pm. With literally no noises or anything to suggest failure.
 
  dan's cast offs.
you use an air line to pressurise the cylinder with the piston at tdc. it's unusual for an engine to have zero compression on all cylinders though.
 
  182/RS2/ Turbo/Mk1
When you turn it over does it just make a "whiiiiirrrrrrrrrrr" sound without the usual engine turning over noises?

If so then the 0 compression results would make perfect sense.

A leakdown test would tell you which set of valves is bent, as like you said, its going to be that not suddenly all the pistons have big holes in them etc.


I assume you have checked that when you turn it over the alternator etc (ie the Aux belt) is turning, just so you know that its not just the starter failing to engage, but Im sure a garage would have spotted that!
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
I'd like to think they've done that, or something along those lines.
I'm more interested in a possible cause, assuming that they were correct and absolutely no pressure in any cylinder?
 
  182/RS2/ Turbo/Mk1
Can only be that the cam and the crank have got out of sequence, failed tensioner, snapped chain/belt, cam pulley come undone, cam snapped off right at the pulley end (although would be unlikely to do all cylinders if it was the last one)
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
When you turn it over does it just make a "whiiiiirrrrrrrrrrr" sound without the usual engine turning over noises?

If so then the 0 compression results would make perfect sense.

A leakdown test would tell you which set of valves is bent, as like you said, its going to be that not suddenly all the pistons have big holes in them etc.


I assume you have checked that when you turn it over the alternator etc (ie the Aux belt) is turning, just so you know that its not just the starter failing to engage, but Im sure a garage would have spotted that!

Can only be that the cam and the crank have got out of sequence, failed tensioner, snapped chain/belt, cam pulley come undone, cam snapped off right at the pulley end (although would be unlikely to do all cylinders if it was the last one)

Sorry mate, didn't see your first post earlier.
Starter is 100% turning, seen it with my own eyes. Looking back now it was whirring much quicker, i.e no compression. Didn't think that at the time though.

Cam chain is in tact from what we're told.

Would all the valves be bent, hence no compression in any cylinder? Is it possible to bend all of them?
 
  Many.
Oddly, this sounds sort of similar to a Audi A4 Cab (1.8 20V Turbo) my mates garage has in atm. It was happily driving when suddenly cut out with no compression. Stripping it revealed 8 bent exhaust valves, no bent inlets, extreamly odd considering the timing belt is fine, and that runs the exhaust cam, with a chain running the inlet cam off of the exhaust pulley.

I'll keep an eye on this thread.
 
  182/RS2/ Turbo/Mk1
Sorry mate, didn't see your first post earlier.
Starter is 100% turning, seen it with my own eyes. Looking back now it was whirring much quicker, i.e no compression. Didn't think that at the time though.

Cam chain is in tact from what we're told.

Would all the valves be bent, hence no compression in any cylinder? Is it possible to bend all of them?


It will have bent at least 1 valve per cylinder if no cylinder has compression, until you leak down test it or take the head off though you will have no way of knowing if its done all of them or just some of them, normally it will be at least all of the inlet or all of the exhausts, ie its unusual to bend one inlet valve per cylinder as they all open together.

Its going to need the head off to fix, that much is all but certain.
 
  Many.
Being four years old, if its been serviced with accordance with Audi's guidelines, there's a reasonable chance of a goodwill gesture of sorts. Either a full job, or least part payment.
 
  clio 182 cup
i cant see it being that the engine has failed. as she obviously drove it fine to work at 8am! and parked it and then later it wouldnt start. is the car actually cranking over? becaise if the starter is spinning and not cranking it over then the bush in the starter has failed. push start the car pal and if it starts then replace starter motor ... the other thing is when u put the car in ignition is the fuel pump buzzing?if its not buzzing then being a 10 plate car it cant be fuel pump could be alarm causing it or immobiliser. another thing is.. get a plug and put it onto the end of the coil lead ..crankit and see if the plug sparks. and then report back on here. its a 10plate audi i doubt its a engine failure. its someting minor thats in my opinion
 
  Many.
i cant see it being that the engine has failed. as she obviously drove it fine to work at 8am! and parked it and then later it wouldnt start. is the car actually cranking over? becaise if the starter is spinning and not cranking it over then the bush in the starter has failed. push start the car pal and if it starts then replace starter motor ... the other thing is when u put the car in ignition is the fuel pump buzzing?if its not buzzing then being a 10 plate car it cant be fuel pump could be alarm causing it or immobiliser. another thing is.. get a plug and put it onto the end of the coil lead ..crankit and see if the plug sparks. and then report back on here. its a 10plate audi i doubt its a engine failure. its someting minor thats in my opinion

It is odd for it to break in such way, but not unheard of. OP said it cranks.

You'll really struggle to hear a fuel pump on a modern car, Plus, I'd imagine on that, it'll only pump when cranking. Furthermore, the factory alarm and immobiliser won't just stop the fuel pump, it'll do far worse than that, inc stopping it from being cranked. Also, this won't have coil leads.
 
  182/RS2/ Turbo/Mk1
i cant see it being that the engine has failed. as she obviously drove it fine to work at 8am! and parked it and then later it wouldnt start. is the car actually cranking over? becaise if the starter is spinning and not cranking it over then the bush in the starter has failed. push start the car pal and if it starts then replace starter motor ... the other thing is when u put the car in ignition is the fuel pump buzzing?if its not buzzing then being a 10 plate car it cant be fuel pump could be alarm causing it or immobiliser. another thing is.. get a plug and put it onto the end of the coil lead ..crankit and see if the plug sparks. and then report back on here. its a 10plate audi i doubt its a engine failure. its someting minor thats in my opinion

Can you give an example of "something minor" that would result in zero compression on all 4 cylinders then please? Bearing in mind that he has already confirmed the starter is definately turning the aux belt etc so must be engaging?


If its suddenly got literally no compression anywhere after being fine right before, then its bent the valves, there just isnt anything else that does that!

How would a fuel pump or immobiliser or sparking issue result in low compression, Im sorry but you really do sound like you havent the first clue about the mechanical side of things, just cause its an audi and fairly new doesnt mean it hasnt failed dramatically.
 
  2003 Clio 172 Cup
The old 3.2 used to suffer with chain stretch. This could be the problem with the newer engines too. Possibly the tensioner hasn't auto adjusted correctly (become stuck) and the chain has jumped a tooth or two on start up. Continuous attempts to start would damage valves if the crank and cams are out of time. After compression check next step is check correct alignment.
 
  clio 182 cup
Can you give an example of "something minor" that would result in zero compression on all 4 cylinders then please? Bearing in mind that he has already confirmed the starter is definately turning the aux belt etc so must be engaging?


If its suddenly got literally no compression anywhere after being fine right before, then its bent the valves, there just isnt anything else that does that!

How would a fuel pump or immobiliser or sparking issue result in low compression, Im sorry but you really do sound like you havent the first clue about the mechanical side of things, just cause its an audi and fairly new doesnt mean it hasnt failed dramatically.

lol sorry matey i aint no mechanic was just putting another idea on the table. im used to rs turbos lol. to op.. can the coil on plugs not have gone down? i have 4 brand new ones here for sale thats why im wondering lol i cant get my head round one thing though.. it was fine when she parked it.. and then later wouldnt start so how could the engine have just lost comnpression etc. maybe the engine didnt sound right on her way to work and she didnt notice? and then it messed up but still surely she would have realised something aint right.. still cant se how it drove ok to work. and then after work woudnt start. and that being a 10 plate car too ..i aint no mechanice though dont know much as you can see lol
 
  182/RS2/ Turbo/Mk1
Shut up about sparks and coils.
The engine has lost compression. You can unplug the coils, throw them in the bin, watch the bin men take them away and STILL it won't change the compression test figures, what you are saying is exactly as unhelpful as if you were blabbering on about the rear wiper motor or the radio.
The OP specifically asked for responses from people who know what they are on about, that isn't you so don't reply.
The timing probably moved on cranking at which point it bent the valves.
 
  clio 182 cup
how do you know the garage aint having him on about it losing compression though . unless he has done it himself or seen the results..theres loads of garages out there to rip u off for things you dont need.
 
  182/RS2/ Turbo/Mk1
how do you know the garage aint having him on about it losing compression though . unless he has done it himself or seen the results..theres loads of garages out there to rip u off for things you dont need.
Because he said he could hear himself that it has no compression from how it turns over.
 

Daniel

ClioSport Moderator
  Whichever has fuel
lol sorry matey i aint no mechanic was just putting another idea on the table. im used to rs turbos lol. to op.. can the coil on plugs not have gone down? i have 4 brand new ones here for sale thats why im wondering lol i cant get my head round one thing though.. it was fine when she parked it.. and then later wouldnt start so how could the engine have just lost comnpression etc. maybe the engine didnt sound right on her way to work and she didnt notice? and then it messed up but still surely she would have realised something aint right.. still cant se how it drove ok to work. and then after work woudnt start. and that being a 10 plate car too ..i aint no mechanice though dont know much as you can see lol

Shut up about sparks and coils.

The OP specifically asked for responses from people who know what they are on about, that isn't you so don't reply.

images?q=tbn:ANd9GcTU4EsrkSzd8dWBEbsNc6cBXmR6JbF8EzixDzaPE_CN080H0UuD.jpg
 

Carbonraider

ClioSport Club Member
  Raider, 172, the van
Can you give an example of "something minor" that would result in zero compression on all 4 cylinders then please? Bearing in mind that he has already confirmed the starter is definately turning the aux belt etc so must be engaging?


If its suddenly got literally no compression anywhere after being fine right before, then its bent the valves, there just isnt anything else that does that!

How would a fuel pump or immobiliser or sparking issue result in low compression, Im sorry but you really do sound like you havent the first clue about the mechanical side of things, just cause its an audi and fairly new doesnt mean it hasnt failed dramatically.

Spark plug failure :p
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
this got heated…!

I know the garage that looked at it, and I know they are competent enough to not mess up compression test, but they aren't specialists in Audi's so weren't too confident.
Heard from my boss today it's gone to another garage who are rally specialists (don't know why) but they are very keen to find the problem so will be looking at valves first.

Also, I have a bet with my boss as he has a new theory. Apparently 2 weeks ago the oil light came on so her fella topped it up but with the wrong grade of oil, 0.5L. He thinks this has had an effect on the engine and due to being a thicker grade has meant the engine is hydraulically locked and the valves are jammed open because of this. I can't see it happening but could there be some truth to this?
 
  Renault Clio182 bean
this got heated…!

I know the garage that looked at it, and I know they are competent enough to not mess up compression test, but they aren't specialists in Audi's so weren't too confident.
Heard from my boss today it's gone to another garage who are rally specialists (don't know why) but they are very keen to find the problem so will be looking at valves first.

Also, I have a bet with my boss as he has a new theory. Apparently 2 weeks ago the oil light came on so her fella topped it up but with the wrong grade of oil, 0.5L. He thinks this has had an effect on the engine and due to being a thicker grade has meant the engine is hydraulically locked and the valves are jammed open because of this. I can't see it happening but could there be some truth to this?

Red or yellow oil light? (yellow being level and red being pressure). If it was just oil level then even in he put 10w50 in it wouldn't kill the engine, especially if it was just 0.5l of oil, compared to the 4/5L it takes to fill it. 1st Theory :Sounds like a simple failed belt/chain tensioner if its gone that quick, as soon as she tried to start the engine it would have jumped causing instant damage with it being and interference engine, and with repeated cranking of the engine (as most people do when the car fails to start) wold just result in even more damage/valve to piston contact.

2nd Theory: Oil was topped up 2 weeks ago yes? maybe she has a bad oil leak and the oil level has become very low again and the oil pressure has dropped too low(maybe not noticed or ignored the light), which would cause the chain to slacken as the tensioner relies on oil pressure, and upon restarting the car its got to the point where its slack enough to jump the teeth on the sprockets.
 
  dan's cast offs.
just remembered hearing about a few killing the woodruf key on the crank pulley. logically it's got to be either that or the chain breaking?
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
Red or yellow oil light? (yellow being level and red being pressure). If it was just oil level then even in he put 10w50 in it wouldn't kill the engine, especially if it was just 0.5l of oil, compared to the 4/5L it takes to fill it. 1st Theory :Sounds like a simple failed belt/chain tensioner if its gone that quick, as soon as she tried to start the engine it would have jumped causing instant damage with it being and interference engine, and with repeated cranking of the engine (as most people do when the car fails to start) wold just result in even more damage/valve to piston contact.

2nd Theory: Oil was topped up 2 weeks ago yes? maybe she has a bad oil leak and the oil level has become very low again and the oil pressure has dropped too low(maybe not noticed or ignored the light), which would cause the chain to slacken as the tensioner relies on oil pressure, and upon restarting the car its got to the point where its slack enough to jump the teeth on the sprockets.

Interesting, and it is the theory I've got my fiver on to be honest.
It was yellow light for low, not pressure apparently, first thing I asked her when she mentioned it! She was cranking it a lot so if this is the issue looks like it could be quite a bit of damage. Salvagable do we think, or new engine?


Very interesting, so may be something Audi end up fixing.

It is full service history to the proper schedule according to her, but is due an oil change at about 48k.
 

Jaff.

ClioSport Club Member
I'd take it to Audi and make a bit of fuss. Fsh and a fault recognised by a manufacturer could mean a hefty good will gesture.
 

Pep

ClioSport Club Member
  M2,XJS,S1000RR
Diagnosis complete, engine is fooked.
Not much info but they've boroscoped it and the cylinders are a right mess, cam chain issue as linked above.

Audi have offered 50% but will still be cheaper for a second hand engine so think they're going that way.

The good news is I won the bet with my boss, every cloud and all that...!
 
  182/RS2/ Turbo/Mk1
Diagnosis complete, engine is fooked.
Not much info but they've boroscoped it and the cylinders are a right mess, cam chain issue as linked above.

Audi have offered 50% but will still be cheaper for a second hand engine so think they're going that way.

The good news is I won the bet with my boss, every cloud and all that...!

Are you SURE its not the spark plug leads instead though?

LOL
 


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