at a complete loss

[cornishtaz]

I'm at complete loss as to what the problem could be with my Ecotec Calibra. Its a right bugger to start and runs very rough when it eventually does. The EM light is on and the fault code points to the cranksensor. This has been changed today as has all the loom from the sensor to the ECU, the timing has been checked and is spot on. All elec connections have been checked and no probs that I can see. Is there a possibility that the ECU is at fault or that the toothed crankwheel has lost a tooth.

Can anybody please please help

[Rusty_CallyT]

i hear its possible the cam sensor can give the same fault

[mickeyboy]

hi matey not being funny but have you check this lot?spark plugs.ht leads.vacuum leak at throttle body,inlet manifold or associated hoses.blocked injector.distributor cap cracked or have you checked for leaking or perished crankcase ventilation hoses?all of these will make it misfire and run rough matey

[cornishtaz]

I've disconnected the cranksensor when the car is running with nochange to fault condition. If I disconnect the cam sensor when running the engine stops, this was suggested by a friend, So I think the cam sensor is ok.

[Animal]

Are you checking the fault code when the engine is running?
If you're not, it will throw the cranksensor fault up on its own.

[cornishtaz]

Bit of an update, the cam sensor has now been changed but still got the same problem. Tried to read the fault codes with engine running but the EM light doesn't flash at all, it stays al the time.
When starting the car the angine turns nice and free for a couple of secs, then it goes tight as if it unable to turn and all the elecs go wild you get some slight backfire, this process goes on for about 3-4 mins when the car eventually starts. Once running the idle is smooth and when you rev the engine its a bit lumpy this continues for approx 5 mins when the cars idles and revs freely upto 4500 and the EM light is on. If you disconnect the cranksensor the fault stay the same but if you disconnect the cam sensor the car stalls. This suggests to me that the fault still lies with the crank sensor?

Anyone got anymore ideas before I throw the towle in and either give it to a garage(expensive) or the car gets broken for parts(don't really want to do as is too good to break)

[cornishtaz]

Now that I'm back from sorting out the Taliban, I've got myself back into the garage to sort out my Cally. It's now had a new cambelt kit fitted, Vaux genuine. I've still got the same problem as before. To recap whats been changed Crank sensor, Cam sensor, Crank sensor wiring, ECU, Cambelt and tensioners.
To recap the fault difficult to start once started idle is rough for a short time then smooths out to approx 750-800 rpm, oil pressure reads 4 bar, the engine will rev freely to approx 4000 rpm where it starts to limit, management light is on and re-read fault codes and it comes up as incorrect crank signal(read above reply for more in depth description)
I'm now completely baffled as to what the fault can be, I've never had a fault which has beaten me but this is coming very close.
Anybody got anymore ideas

[M6 AXL]

First off, glad you made it back. (from sorting out Taliban)

Has the car recently had an engine change? If not try refitting crank sensor, sometimes they need a knock for them to sit right.

[cornishtaz]

Thanks for the welcome back.

The guy I bought the car from didn't mention it had had an engine change he was driving the car when the fault occured and the AA suggested it was the crank sensor which he changed and didn't cure the fault so he sold it on cheap (£100). The sensor is seated correctly and has been tightened to correct torque

[nigescalli]

hi mate this may sound daft but just check your cat hasnt collapsed as it will cause back pressure on your engine causeing them symptoms

[cornishtaz]

There's no cat fitted, I need one for the MOT if anyone got one for a 94 M plate

[nigescalli]

<!--QuoteBegin-cornishtaz+--><div class='quotetop'>(cornishtaz)</div><div class='quotemain'><!--QuoteEBegin-->There's no cat fitted, I need one for the MOT if anyone got one for a 94 M plate<!--QuoteEnd--></div><!--QuoteEEnd-->there was one on ebay earlier

[cornishtaz]

I noticed that but it was for the later Calli Ecotec

[markie]

have you checked that the head gasket might have blown and water sitting on top of the pistons.remove the plugs and wind her over and see if it pushes out any water

[cornishtaz]

Will do a compression check tomorrow but don't suspect the head gasket as when I picked the car car up I drove it 160 mile back home and it was fine with no oil or water loss