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Okay heres the story... (Na6 with B6 engine turbo conversion)

Drove to my mates place, no problem and i turn into the driveway it starts sounded like a vw boxxer engine! then the engine died. tried starting it again and it was the same. and the headlights wouldnt go retract back down.

Got out and left it for abit. then got back in the boot to make sure the negative and positive terminals wasnt loose. then it started and ran fine.

Few minutes down the road i open it up, it started hesitating 4-5000rpm?
Then it dies again. Pull over and the car cranks but no starting. Left it for bit again and tried again, engine on start up hesitating 3-4cyl? And now loud noise of metal problem inside? But coming from the top end of the motor. Battery has 12vdc. Couldnt check if it was charging the battery though cause it woulndt run long enough keept wanting to stall.

I think the posibilitys are:
1) altinator died
2) Battery Died
3) Coil pack (do have spare but havnt tried yet)
4) Leads (only replaced them 1month ago
5) Fouled spark plugs?
6) engine wise: hydralic lifter/s failed? causing loud noises intop end.
7) valve burnt?

yet to do a compression check. has good oil pressure on cranking.

Any thoughts or simlar experiances? espically the Hydro Lifters failing!?

Thanks

start with the easiest thing to check.. plugs..

not sure about the rest.. im sure someone will know what it is

Yes, try plugs and leads.

You won't believe how horrible they run and sound when the the leads/plugs quit. When my NA did it, my first thought was a mechanical failure.

Thought about fuel supply?

The fuel pump takes a while to build up pressure, you use the pressure up when you start to drive, engine fails, pump starts to make pressure again, after a while it's drivable again, you use the pressure up, engine fails, pumps starts ..... get the picture?

Fuel filter blocked? Fuel pump dying? Crushed fuel line? etc

I went through this on friday. Try plugs and leads first. When I pulled out the leads, white powder went everywhere.

I bronze brushed the spark plugs, swapped out the leads with some old ones I had. Runs like new now.

Symptoms were same as yours. Rough as guts idling, almost stalling. No power with lots of hesitation. Got worse as the revs slowly climbed.

1 second it was running fine, took off from the next set of lights and it was aweful.

it starts sounded like a vw boxxer engine! ... have you checked the exhaust manifold and intercooler plumbing for a leak/loose pipe?

hmm i pulled the spark plugs out. 1,2 okay, 3+4 electrode sqashed against the plug. Looks like either something has got in the bore and it sqashed it. Or the rods have streatched and traveld up to far? Bent valves? also maybe?

Looks like im going to have to pull the head of at least see what the dammage its.

Replace the plugs with some old but intact ones...

Pull the leads off to prevent it firing (or the CAS)

Turn the engine over - that will possibly let you know if something is banging around in there, particularly if you pull the plugs back out and they are damaged.....

I suppose you could also turn the engine by hand - looking down the plug shafts and see what you can see.....

rjr666 wrote:Or the rods have streatched and traveld up to far?

...or disconnected at the crank......or broken..........or the piston tops have come off.

well i turned the motor over with no plugs in by hand and no noises. and then also without coils connected. no noises... strange.

Might messure the height of each piston at the top of each stroke and see if there even.

If something had broken like piston ect, i would have thought the noise to be louder while it was cranking over.
hmmmM

Compression test could reveal an imbalance indicitive of a piston/rod failure.

Doesn't sound too good though

How much boost have you been running?

That's VERY strange. Our engines are non-interference so even if the timing belt went, they still wouldn't touch the valves.

Well ive been running 1bar with spikes to prob 1.2bar. even had a 1.3spike once (greddy memory boost gauge)

The engine was rebuilt with wiseco 8.5-6comp ratio pistions, gtx conrods shotpeened. new bearings, arp bolts, metal headgasket, Standard head. (done about 5000kms on the engine now) Been some fairly hard ones high revs. Running it was fine.

Could geta borascope and have a lookinside. but i think the best solution is to pull it out. strip it down.

Why would you strip it down without even doing a 5 minute compression test?