crank position sensor keeps going

[ABLACK6]

crank pos sensor keeps going bad in my gn. Any ideas why this keeps happenning? car runs great until it just DIES and will NOT restart. prob has been bad crank sensor 2 times in a row. 1st time it ran great for 1 week before it went again. It was kind of oily, so i'm assumming that might be reason? Something has to be causing it to keep going on me.

 

[pacecarta]

loose balancer or a bad balancer ,
if its wobbling and hitting the sensor it will kill the magnet in the sensor
check the clearance on the sensor then rotate balancer a little and recheck and continue until youve checked the entire reluctor ring clearance , it has to be centered in the slot at all points, if it s the reluctor ring is good but the balancer could still be wobbling at rpm

check the balancer bolt torque , 220lb/ft
remove it and check for cracks on the neck that slides onto the crank

the fix might require a new balancer

btw what method did you use to determine the crank sensor was in fact bad , did you verify the absence of a signal on the output wire

 

[jasjamz]

A bad ignition module will do that too. It happened to me and John@ Caspers helped me out.

 

[ABLACK6]

thanks guys, im about to put it away for winter but doing complete tune up in spring including new coil, since im thinking a COIL is the prob.

 

[tttype]

Cant see sensor going bad without being chewed on be the ring.

Coils wont have anything to do with crank signal, but crank & cam sensor signals have to go through the module.
This keeps module makers in business.

 

[Benched]

What method did you use to set the crank sensor?

 

[87GNSteve]

You should put some machinists bluing on the crank balancer tabs and see if it is making contact while on the road.

 

[Turbo Loyd]

Was putting the final touches in the assembly of a friends engine once and found one of the leading edges of the reluctor was tweaked and would slightly touch the crank sensor while the others were perfectly centered. Could not find a compromise setting.

Had to make a slight adjustment with a small hammer to make the adjustment for all three leading edges to be centered. so as pacecarta indicated above it is important to check the clearance at multiple places. I always used a matchbook cover, but I bet they are harder to find now

 

[chopped39]

Are you around chicago or suburbs? I have the tool to check the ring and sets airgap on sensor.

 

[ABLACK6]

a few hours south of chicago. But i'm just gonna take it in and have it checked before I put it away for the winter. thanks

 

[jasjamz]

Did you see any rubbing marks on the ones that kept failing? Did you replace the ignition module under the coil pack? I would bet it is your problem not the coil.

 

[ABLACK6]

ok thanks i'll have to check that out.