Camshaft Position Sensor, anyone with any experience?

[Trainman]

So my motor has developed a tick that has been getting worse, the dealer suggested running that valve lifter cleaner stuff for a couple of oil changes but it is still getting worse. Then on the weekend, it threw 2 codes, one an O2 sensor and the other a cam positioning sensor.

 

Dealer is suggesting the following: Check both the sensors to make sure they are working, replace if required (they are some sort of solenoid that activates the cam adjusters). About 1 hour labour plus parts.

 

If they are OK, then it is a big front end job to inspect, clean and replace if required (at $400 each) the actual cam adjusters. They estimate almost 16 hours to do this as it is essentially the same as replacing the timing chain. So worse case it will be pushing $3,000 with taxes and parts.

 

Has anybody had any kind of experience themselves with this? They mention that as these parts are all hydraulically activated, that they can get "gunky" but I have been using full syn oil for the last 40,000 km and since I bought the beast, with 60,000 km (it now has 143,000 km) the oil has been changed every 5,000 km, dino or syn.

Edited March 19, 2008 by Trainman

[91path]

So my motor has developed a tick that has been getting worse, the dealer suggested running that valve lifter cleaner stuff for a couple of oil changes but it is still getting worse. Then on the weekend, it threw 2 codes, one an O2 sensor and the other a cam positioning sensor.

 

Dealer is suggesting the following: Check both the sensors to make sure they are working, replace if required (they are some sort of solenoid that activates the cam adjusters). About 1 hour labour plus parts.

 

If they are OK, then it is a big front end job to inspect, clean and replace if required (at $400 each) the actual cam adjusters. They estimate almost 16 hours to do this as it is essentially the same as replacing the timing chain. So worse case it will be pushing $3,000 with taxes and parts.

 

Has anybody had any kind of experience themselves with this? They mention that as these parts are all hydraulically activated, that they can get "gunky" but I have been using full syn oil for the last 40,000 km and since I bought the beast, with 60,000 km (it now has 143,000 km) the oil has been changed every 5,000 km, dino or syn.

 

1)try reseting computer-pull fuse for computer-wait 5 min-

replace fuse. go for a variable ride-to set up pewter. check codes

 

2)use heavier oil-10w30 or 10w40 to stop tick.

 

3)dont leave engine cleaner in--drain it out with oil change

Edited March 15, 2008 by 91path

[5523Pathfinder]

Oh fun! First, good thing you are changing the oil on a regular interval. 5000k is about perfect. Do you know how much oil you are putting in? IIRC, it should be around 5 1/4 quarts. I would double check the oil level first. Second, I would try an listen to where the noise is coming from. I have replaced both the cam sensors before as well as the timing solenoids, so a part not working is not out of the question. There is a TSB about double checking the oil level, and verifiying proper oil pressure. A engine flush might help loosen up things if there is something sticking or gummed up. What I have found more than anything, is people taking thier vehicle to quick lube places and having the wrong amount of oil put in the vehicle. Do some poking around and let us know what you find.

 

Oh, and if the solenoids need replacing, its actually pretty easy. 3 bolts and 1 connector and they are right on top of the engine.

Edited March 15, 2008 by 5523Pathfinder

[Trainman]

Oh fun! First, good thing you are changing the oil on a regular interval. 5000k is about perfect. Do you know how much oil you are putting in? IIRC, it should be around 5 1/4 quarts. I would double check the oil level first. Second, I would try an listen to where the noise is coming from. I have replaced both the cam sensors before as well as the timing solenoids, so a part not working is not out of the question. There is a TSB about double checking the oil level, and verifiying proper oil pressure. A engine flush might help loosen up things if there is something sticking or gummed up. What I have found more than anything, is people taking thier vehicle to quick lube places and having the wrong amount of oil put in the vehicle. Do some poking around and let us know what you find.

 

Oh, and if the solenoids need replacing, its actually pretty easy. 3 bolts and 1 connector and they are right on top of the engine.

 

The servicing is done at a local shop, no quick lubes in my small town Oil level and pressure where the first things looked at, all is OK. It has never burnt a drop. And just to clarify, the oil and filter are replaced every 5,000 kilometers or about every 3,100 miles.

 

Sound is coming from the right side of the motor, more noticeable towards the rear.

 

There has been a history of the valve timing sensors doing weird things in this truck and the dealer did a flush a couple of years ago (long before the ticking noise started).

 

As for replacing the solenoids, the dealer said it would take about 1 hr to remove and bench test both and re-install/replace, so not too bad. I sure hope that is all it is. And I will get an oil flush done at the same time I think.

 

Interesting thought about heavier weight oil, will talk to the dealer about that. This may be an unexpected side effect of going to full syn?

 

Thanks for the input, I will update on Tuesday after the dealer looks at it.

[02silverpathy]

ugh, I can only hope that it is not a manifold issue. I thought that I read here that there was a manifold issue even with the 3.5's. Maybe it was in the power valve thread?

 

Flushing: this needs to be done gradually, reason being if there is ANY build up in your motor (doubtful), you want to remove small bits at a time otherwise you can clog small oil valleys and cause new problems. I would put 5 qts of the 5-40 synth in with that 1/4 quart being ATF to help cleanse....did you get your PCV changed? This thing cuases lage amounts of build-up during acceleration.

 

I know that chain tensioners on the 98-01 Altima go bad and cause a clicking (I have an alty), which is the tensioner feathering into the timing cover...and yes it is hydraulic also...try making a stethescope with a long screwdriver (or buy a steth) and klistening to the chain cover!

 

Hope this helps,

Keep us updated!

[Trainman]

ugh, I can only hope that it is not a manifold issue. I thought that I read here that there was a manifold issue even with the 3.5's. ....

 

Keep us updated!

 

Ha, it wish was the manifold, way easier to fix than trying to get at the cam shaft sprockets. We have already ruled that out, so its down to the cam timing or valve adjustment.

 

And for sure I will keep you up-to-date.

[Trainman]

She was at the dealer today, this is what they found:

 

The cam actuators are working fine and they were able to isolate the noise to the rear of the right head. They now believe that the a lifter has collapsed. So it needs to go back as they need more time plus some parts. That will be next week sometime. I will provide another update then.