Possible cam sensor issue......nb8a?

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maxgus
Fast Driver
Posts: 364
Joined: Tue May 29, 2012 10:35 pm
Vehicle: NB8A - Supercharged
Location: Brisbane North

Possible cam sensor issue......nb8a?

Postby maxgus » Sat May 04, 2013 9:09 pm

Hey guys I have been painting a valve cover over the last two weeks and decided to change it over today along with new gasket. I believe I have done everything correctly. The car will start and idle but as soon as you accelerate it hits 2000rpm and drops to 1500rpm then bounces back to 2000 and repeats this for a few minutes eventually coming good. I have noticed that it sometimes idles a little higher than usual and has a little bit of idle dip that it didnt have before. I have checked everything 2-3 times over and the only thing i can think of is that the cam sensor was on its way out and the move was too much for it. The car is a 1999 nb8a with 195,000ks.

Any help would be appreciated.

I have read some earlier threads that make believe this is the problem but would love a second opinion.

Thanks
Angus
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93_Clubman
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Re: Possible cam sensor issue......nb8a?

Postby 93_Clubman » Sun May 05, 2013 11:02 am

Given this issue has developed after changing over the cam cover, it would also be worth checking the wiring to the coilpack as it deteriorates where it deflects just prior to plugging into the coilpack. Apparently the combination of deflecting & not being well supported in this particular spot, probably compounded by alternating high & low temperatures, weakens the wires. It's not immediately apparent to the eye, but if you move this part of the wiring loom around while the motor is running you'll get a response in terms of idle if there's a problem.

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MrRevhead
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Vehicle: NA6
Location: NW Sydney

Re: Possible cam sensor issue......nb8a?

Postby MrRevhead » Sun May 05, 2013 11:41 am

It might also be worth checking/cleaning or replacing the PCV Valve as that can also affect idle.
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maxgus
Fast Driver
Posts: 364
Joined: Tue May 29, 2012 10:35 pm
Vehicle: NB8A - Supercharged
Location: Brisbane North

Re: Possible cam sensor issue......nb8a?

Postby maxgus » Sun May 05, 2013 12:21 pm

I have cleaned the valve and will check wiring later.

Thanks
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maxgus
Fast Driver
Posts: 364
Joined: Tue May 29, 2012 10:35 pm
Vehicle: NB8A - Supercharged
Location: Brisbane North

Re: Possible cam sensor issue......nb8a?

Postby maxgus » Sun May 05, 2013 7:47 pm

I checked wiring and seems to be fine. Unplugged everything and gave it clean. Pulled spark plugs and cleaned as well. Checked for oil leaks and found none. Cleaned points in coil pack as they were a little crusty. Happy to say that car is running fine now. Hopefully will stay that way. Cant be sure what was at fault.

Thanks for the suggestions. I find this forum very helpful.

Thanks
Angus
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