Possible Turbo Problem, any help?

[DrGloucester]

I have a beautiful S2Avant 93,000 Mreg previous owner (and good friend) looked after the car for 8 yrs.
Last week after a moderate 20km drive it started to judder and now drives very sluggishly. It fees like one of the cylinders is not fireing.

There is also a very odd, dry smell (a bit like burning bakelite) coming out of the exhaust (not eggy nor burning oil).

I've got the car booked in with QS Tuning http://www.qstuning.com/index.jsp next week, but its a 30 minute drive away. Can anyone advise me what the problem might be and if I'm likely to do more damage by driving the car to the garage?

Yours unsure, David

PS PLugs anad leads are fine.

[Jas11n]

Does it tick over very lumpy? Lacks power and vibrates like hell?
Then sounds like it's only running on four or less cylinders.
Have you had the disgnostic codes read? They will tell you if you have an injector that isn't working. Unfortunately they won't tell you if it's a bad coilpack or power output stage.

To check which cylinder is off, starting at the front unclip and remove then replace an injector multiplug one at a time. When you come across one that makes no change, then thats the effected cylinder.
Leads? it doesn't have leads in the normal sense. It has wires leading from each coilpack out the back of the coil cover.

It could be one of many different things, one channel of a power output stage has gone, a duff coilpack, a break in the wiring to a coilpack, a duff injector.

Above is assuming it's running on less than the full 5 cylinders based on your description (dry weird smell, no power and juddering). More info needed.

Jas..

[Acidburn]

Good info there jas forgot to add in the comment I heard about yours when one of your coilpacks went down

sounding like a scooby

The info that jas has given sounds like the best approach and easiest way to check out before spending out on stuff like new turbo's. Btw do you have a boost guage fitted?

[DrGloucester]

Jas

- Spot on with "Does it tick over very lumpy? Lacks power and vibrates like hell". You've clearly given me some good advice, thanks for taking the time to post it up.

In case you had not guessed I’m a complete novice when it comes to understanding high performance engines; previously I've only played around with the engine on a 875 cc on a Hillman Singer Chamois check out this link to see how basic the engine is

http://www.theimpclub.co.uk/forum/album_page.php?pic_id=4395

Acidburn - thanks also for seconding Jas' comments it all helps.

I will post an update on the thread later in the week.

David

PS No boost gauge fitted

[Jas11n]

Hi David, ok sounds like it's running on four.

Not unheard of for an injector to fail, but I'd be surprised if it was. They usually just age and don't supply the "correct" amount of fuel or leak rather than completely cease to provide any fuel.
Coilpacks do fail, especially as the cars are now 10 years old or older. Most of the time it's wiring related as the insulation cracks due to heat and age.
"Usually" a failing coilpack will give a misfire in highload circumstances rather than just completely dying altogether.

Most likely suspect for a complete failure on one cylinder, is a dead channel on a power output stage. These cars use two POS's, each with three channels. Being a five cylinder you have one spare channel on one of the POS's for a "one time" free fix.
It's a little involved swapping pins about inside the multiplug connectors for someone who is a little unsure.
This webpage >>> "LINK" gives good information on doing this free once only fix (this is assuming it hasn't been done already in the past). The webpage is giving info on the POS layout on a URs4, but the only difference is they are mounted slightly different than they are in the ABY engine bay.
I've put some pictures below to show you where the POS's are located in an ABY engine bay, and also what they look like.

To go back to what I suggested in the first post, try removing a multiplug from an injector one at a time. Unhook the first and listen to the engine, it no change then reconnect it and move on to the next. Do that until you hear and feel no difference in the idling of the engine. That has identified which cylinder isn't running. The injector multiplugs are the black plugs that attach to the injectors on the black fuel rail that runs along the engine in the middle of the coilapack cover (20v turbo) and the inlet manifold.

If you do need to drive the car to a garage (or drive it anywhere now for that matter), then in my honest opinion you need to identify this non running cylinder, then remove the multiplug for that cylinders injector before you set off. This will stop fuel being injected into that cylinder and possibly washing the bore with petrol/getting petrol in your oil.


Location of Power Output Stages,


A Power Output Stage

[DrGloucester]

...and finally a thank you.

Jas
thanks again for your first (spot on) post. I did in fact have a dead coil pack.

To leave it there would be very dull of me! I followed your advice in the second post and identified which cylinder was out, but I was still uncomfortable about driving the car as getting petrol into the oil does not strike me as a good way to prolong the life of the engine ;-)

I'm not going to pretend I have the time or know how to have fixed the car myself but it helped a great deal to identify what was happening and what I needed ask for when going to the garage.

That said I want to recommend QS Tuning who the previous owner found and who understood the problem and fixed it in an afternoon (charging just 1 hours labour). The owner (Kim) attends lots of meet and is a pure petrol head. Check out the site for details of tuning upgrade that will take you from 230 to 420bhp :-)

Acidburn - yes you have stumbled across me on facebook :-D

Until next time!

David

[Acidburn]

Acidburn - yes you have stumbled across me on facebook :-D

Until next time!

David

Ah so thats who you are lol, I remember now commenting on this thread glad you got it sorted.