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Hi all,

 

Last new thread for me today (promise!). Had a problem with a stuck injector causing a hydrolock in one cylinder, enough to stop the engine from turning. Just wondering if this could have caused the cam belt to slip a tooth? Not even sure if it's possible to slip a tooth!?

 

The timing seems to go 'out' for no apparent reason, I set it correctly (not using the loop on the PTU!), check it again at a later date and find it 10 or more degrees out! Could this be a CAS problem? Any other possible causes? Engine temperature sensor appears to be working correctly. This problem first happened to me quite some time ago when the car was otherwise running well, timing suddenly advanced 10 degrees and caused severe detonation, checked, retarded and it was fine.

 

Thanks in advance for any help.

 

RobH

Featured Replies

  • Author

Pulled coil pack #1, length of HT cable with a plug cap on one end and the other end stuffed into the coil pack, sensor from the timing gun between plug cap and plug. (should be) much more reliable than the loop, which is known to cause problems.

 

Cheers

H

would it be worth doing a cas test you recon topless? his car wont rev past 2500rpm so wouldnt that point to maf?

Haven't seen the 2500rpm, if that is the case then yes, other things to make the timing jump are the tps and neutral switch.

  • Author

Hmm...TPS is relatively new (few years, very few miles on it) and is reading correctly. Neutral switch is a bit of an odd one though...not thought about that really, it was new when I converted to manual about 5 years ago. Doesn't seem to show up in the limited consult test I have.

 

It will rev to 2500+ when in neutral (i.e. no load) quite different to when the MAF is disconnected so I've kind of ruled out the MAF as the problem.

  • Author

Have replaced injectors, replaced ECU ROM, ECU reset, consult fault code dianosed nil defects, disconnected MAF, replaced O2 sensors, checked for injection and spark at all cylinders (present), checked fuel pressure, TPS checked etc etc, the only things I haven't done which seem possible culprits are CAS test, replace PTU (was a new series 2 about 5 years ago) and replace ECU unit as a whole and I guess a compression test wouldn't hurt (or it might)...

 

Haven't checked for electrical continuity to ECU connectors yet, want to narrow the fault down a bit first...as it is I'm grasping at straws..

Man i know the feeling.... im struggling a bit too. although its looking pretty positive at the mo, only getting a bit of hesitation and running rich which is most def the o2 sensors which are reading lazy.

 

You getting any kinda smoke at all? black?

 

anyways cas test next would be a good idea.

But wait to see what mark suggests.

  • Author

yep, plenty of it, deffo running rich. Used £20 of fuel just sat on my drive scratching my head!

yep, plenty of it, deffo running rich. Used £20 of fuel just sat on my drive scratching my head!

 

pmsl hah mine did too...thought my fuel gauge was broken.

 

hopefully your injectors are sealed ok, what if they are leaking like a gooden :(

Im sure you replaced all the bottom seals?

  • Author

yep, all seals replaced, actually got a complete 'known good' fuel rail with original injectors in there at the moment. Connected my 'suspect' fuel rail to the fuel lines whilst out of the engine and switched on, didn't leak a drop under pump pressure, think I can more or less rule out injectors and seals as it's performed equally badly with 2 different sets - both of which are now known not to leak.

I had same prob ,As a last resort used the P.T.U Set 15 deg and has been perfect ever since . Then i go back to try coil 1 and it changes slightley but reads 17-20deg! ptu sits bang on 15 deg and i get no more det.

>> The timing seems to go 'out' for no apparent reason, I set it correctly (not using the loop on the PTU!), check it again at a later date and find it 10 or more degrees out! Could this be a CAS problem?

 

yes, could very well be a faulty CAS or worn out camshaft tab.

Although the fuel-hydrolock can definately have caused the belt to slip one or more teeth

  • Author

Cheers, will have to pull the cover off and have a look I s'pose :-(

  • Author

Yep, it was ;-)

 

TBH I think it's well on the road to recovery, just took it for a spin and apart from dreadful misfiring/backfiring/general roughness and an assortment of extremely embarrassing noises I was reasonably happy. I know I have some dubious injector connectors and my plugs are badly fouled, once I've replaced these I'm expecting an improvement...

 

Cheers

 

H

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