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[kluku5]

Just another thought I had.

Does a faulty knock sensor leave a fault code, or can it not leave a fault code?

Thing is, when I got the car back from the garage, it idled PERFECTLY and ran great, just had a big loss of power, and as said before, didn't hit the rev limiter.
No knock sensor fault code however...

[Andy H]

The automatic gearbox has a small diameter plastic breather pipe that should be open to atmosphere.

There have been cases of people connecting this pipe to the vacuum pipes and then drawing automatic transmission fluid into the engine. Smokey...........

The other issues sound like poor electrical connections I would check that all the connectors in the engine bay are securely plugged together. I would start by checking the big round one under the power steering reservoir.

[kluku5]

Gearbox breather pipe is open. I was also thinking I need to check all the plugs and cables too just in case

[des.allen]

As Mark said earlier, re check ht leads at dispack, it is easy to get them wrong if you just presume the order, I once did it the wrong way and had very simular problems.

[kluku5]

Well, I found something else that probably causes bad stuff.

Stripped it down to cambelt. Both cams on bank 1-3-5 are on mark, intake cam on 2-4-6 is off by a tad, and exhaust cam is off by about a centimetre.
Some pics:
Exhaust cam 1


Intake cam 1


Intake cam 2


Exhaust cam 2


Am I correct that the marks are supposed to go 1-2-3-4 and be in place every turn around?
I also found this, I believe it's the knock sensor on bank 1-3-5:

It had made acquaintance with aux belt tensioner. I scraped it a little more, only to find that both wires are ok, so I put some isolation around it and taped together.

[Andy H]

Yes, Cam 4 appears to be 2 teeth out.

Nail varnish is an indication that at least one belt change was carried out without the timing tools.

It is quite common for the knock sensor wire to get trapped by the auxiliary belt idler bracket. If someone has been careless with the cam sensor wiring they could have been equally careless with the knock sensor.

[kluku5]

Thanks for your reply.

Those 2 teeth I think have a big influence on the engine, and are probably the reason why it's running so rough?
I believe I should try to check if valves are healthy too, or does compression test suffice?

Do you think it would also be worth to do head gaskets aswell, or leave them as is, since I haven't seen any symptoms of them being bad?

[Kevin Wood]

V6 head gaskets rarely give any trouble but the timing is well out, as mentioned.

I would time it up using the proper kit and see if that improves things. If not, try a compression check in case there's some valve damage.

[kluku5]

Ok. Will need to wait for the next paycheck as I want to put on a new belt, don't have the courage to test with the same one. That is if I find a locking kit near me.

One question though, does the aux belt and cam covers need to be installed to to a compression test?

[Andy H]

Ok. Will need to wait for the next paycheck as I want to put on a new belt, don't have the courage to test with the same one. That is if I find a locking kit near me.

One question though, does the aux belt and cam covers need to be installed to to a compression test?

Auxiliary belt not required.
Cam covers optional (the cams won't turn fast enough to spray oil everywhere)

I would get the timing right before trying anything else.

Just be careful not to catch any loose wires in the exposed moving parts.

[kluku5]

Will do.
Cheers

[kluku5]

Update.

Cambelt changed. No change in engine running, cams and crank were put in mark. Hopefully tomorrow I can do a compression test.

However, one thing has come to mind. Could it be that I have blocked exhaust? Because if exhaust was clear, I believe exhaust smoke would go out of the exhaust pipes, not from exhaust manifolds (I think) so much, as I have described in another post..? Ofcourse the manifolds probably are leaking too, but I think that most of the gases would still escape out the pipes, rather then press out from the manifolds?

Also, the engine is having difficulties turning over. It does turn over, but it is very clear that engine/starter is pushing hard to do so. Is it possible that if I do have blocked exhaust, those 2 things are connected?

[Webby the Bear]

Kluku, can I just check something.....

those pics of your camshaft during the timing check....

when you shot those the crank was at TDC, right? and that's what where each cam was with the crank at TDC, right?

if so do compression test and then if down do leak down test which will show if inlet or exhaust valves are leaking 

[kluku5]

Yes that's where each cam was with crank at TDC. How can I do a valve leak test with head still on the engine tho?

[Webby the Bear]

Yes that's where each cam was with crank at TDC. How can I do a valve leak test with head still on the engine tho?

Well it was cams 3 and 4 that were out (4 mainly). if you do a leak down test...

http://www.youtube.com/watch?v=WgrfT0LFMhc

and you get noise/air rushing out the tail pipe or the throttle body then youll know which head to pull off and which valves to inspect