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[jonny2112]

Cheers guys 
Another positive step, though will obviously depend on the results 

[Webby the Bear]

also to work out roughly what psi youre looking for on each pot....

atmospheric pressure (14.7) X compression ratio (which i believe is 10.8:1) = 173psi

someone may need to double check that though as i have been drinking 

[05omegav6]

Iirc the official 3.2 figure is 9.5 bar, presumably in a new engine, so just over 9 would be perfectly acceptable if its done a few miles

[hotrod222278]

Sorry for barging in on the party but could you have maybe pinched a cam sensor wire while working in that general area, I just seems a bit off to be having compression problems when it was working perfectly well before you had the plenium, cam covers and timing covers off.

Shot in the dark I know but I agree with the guys about the misfire and the evidence from the codes certainly suggests electrical over mechanical, just a thought as knackered cam sensors can still run an engine, just really poorly! we are rooting for you fella.

If im wrong please feel free to tell me to wind my neck in and ill go back to just keeping up with the posts

[albitz]

I completely agree tbh,but it wont do any harm to check compression before a member has to suffer sleazyjet to go and have a look at it.
Nipped wire would be worth having a look for,although Im not sure it could cause it to run that rough.

[jonny2112]

Cam sensor cable runs from the cable tray, but to where? It's the knock sensor that runs around the front of the cam cover, isn't it?

[JamesV6CDX]

Cam sensor cable runs from the cable tray, but to where? It's the knock sensor that runs around the front of the cam cover, isn't it?

If the cam sensor wiring was damaged I'd expect a code :/

[jonny2112]

Thought that myself. Just checking.

[jonny2112]

Cleared all the fault codes today with one of those diagnostic things, but there are no codes now after startup. I think I'll have to drive it to get any codes back.
Also thought that I would try disconnecting the MAF, only because it was handy, and oft mentioned. No change though to running 
Anything else worth unplugging to test with engine running?
Or is that a stupid idea 

Oh, and haven't got round to compression test yet. 

[05omegav6]

Does it run any better with the codes cleared

[jonny2112]

No mate, still noisy 

Just a thought too ....... if I unplug something and there is NO change, that could mean that either the part unplugged has no bearing on the issue, or it is already defective ...... 

[05omegav6]

Hmmm bit of both, but as a basic rule of thumb, if unplugging something improves the symptoms then that part is probably dead, if it worsens then the part is probably ok. No change would also suggest that that part has no bearing on the issue.

If one part makes no change, and unplugging everything else makes it worse, then that 'no change' part could well be faulty

Hth, Al

[jonny2112]

Would unplugging cam or knock sensors, for example, with engine running have any ( further ) adverse effect?

[jonny2112]

Well, just collected the car from the garage with no real change. Only fault code was the MAF which was probably as a result of me unplugging it. No other codes or anything showed up. Weird!
Still as noisy, like bad tappets, but not lumpy or anything.
So, driving home the engine electronics symbol starts to flash, and stays on permanently for about the last mile ish of my journey. Now it feels a bit lumpy. Got home, switched her off and back on again, and the light goes out as normal. Checked fault codes (pedal) and got three -
0300 random misfire
0304 no 4 misfire
0325 knock sensor bank 1.

So no further on really. Next step - replace plugs and carry out compression test. Might throw a can of Wynns treatment into it, and maybe have another look at the timing too.
Feel like I'm flogging a dead horse now, but if anyone has any other thoughts please just let me know.
I think I'll be looking for a mobile mechanic soon .......

[albitz]

I still think it will be something simple and probably igntion related.Im no expert though,far from it.