Camshaft Position Sensor problem after head reasembly

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solocreation
Posts: 18
Joined: Wed May 09, 2012 7:47 pm
Car: 2002 Nissan Sentra SE-R Spec V
Location: Charlotte, NC

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I had multiple cylinder missfire for a couple months. Started with cyl#3 then multiple. Did a compression test and it was fine at the time but did not do a leak down test. A few weeks ago the engine started shaking and running rough only at idle and sometimes during acceleration you could feel the misfire. Something major was clearly wrong and after diagnosing it I found water in two cylinders. It was clear that the head gasket was kaput. I just got the car back from the shop after the gasket was replaced and head work was done. When I arrived to pick it up it wouldn't fire up. We found out that by moving the camshaft position sensor slightly, it would fire right up and ran pretty smooth, but as soon as the bolt was tightened down on the sensor it wouldn't fire up. I have the OEM sensor which is good and a cheap Autocraft and same results with both. I don't know much about the head but research has lead me to believe there might be an inadequate gap between the sensor and the relluctor since by moving the sensor around and not bolting it completely down, it cranks right up. Also after driving for a few minutes the low oil pressure comes on only at idle. (first time I've ever seen this light come on and I've driven the car 60,000 miles since owning it) When the check engine light comes on with low oil pressure light the engine shuts itself off. Does anyone have any ideas what might be going on? If the head is in question and I take the rocker cover off, is there anything that I can look for that may be causing this problem? Any help would be awesome! Thanks!


User avatar
solocreation
Posts: 18
Joined: Wed May 09, 2012 7:47 pm
Car: 2002 Nissan Sentra SE-R Spec V
Location: Charlotte, NC

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Finally figured out what was wrong. Cheap mechanics didn't time the intake and exhaust cams properly and improperly reinstalled JWT balance shaft removal. The JWT balance shaft removal kit was reinstalled so badly and backwards that the crankshaft scared the baffle plate and the block-off oil feed spacers dowel pin wasn't in the oil feed hole. Also they went ape s*** crazy with RTV sealant on the timing cover and parts that didn't need it and blocked off oil to the VTC components. There was allot of other small things that they made a mess out of. Once I get this bad boy back together I feel confident it will eliminate the P0340 trouble code and the low oil pressure light...This is all new to me, I'm not an expert but have found reliable help from an mechanical/electrical engineer who's helped me along the way. I've been documenting this project every step of the way, once finished I will post for future reference if anyone comes across similar symptoms after a head job.


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