Knocking Sound from Engine after hall sensor replacement

Knocking Sound from Engine after hall sensor replacement - Printable Version

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Knocking Sound from Engine after hall sensor replacement - billyblue360 - 10-04-2012

Ok I think I may have gotten myself into some trouble. Long series of events but here is what happend.

I was replacing my hall sensor because of a broken plug.
Took the old one out. Notice the sensor portion was missing
Replaced it with the new hall sensor
while doing up the valve cover bolts one snapped off (not sure why because I was using torque wrench at 7ft*lbs
I drilled out the bolt put in a helicoil to fix the snapped bolt.
I connected everything up and when I started the engine that was a loud knocking noise. I didn't run the engine long but it sound like it was coming from the distributor area. Not a 100% sure though
I took off the top timing belt cover to see if I could see anything but didn't notice anything unusual.

I think what my have happened when I removed the old hall sensor the sensor part fell off and I didn't notice it in the distributor. Other than replace the hall sensor I didn't touch anything else. Any thoughts on what could be wrong and what steps I should take to diagnose the problem?

Billy

Knocking Sound from Engine after hall sensor replacement - flash - 10-04-2012

well, obviously you need to pull the cover off and look around in there. might not hurt to pull the plugs, disconnect the coil, and rotate the motor to see what might be interfering

Knocking Sound from Engine after hall sensor replacement - MB968 - 10-04-2012

There is a somewhat close fit between the hall sensor and the rotating cup that is connected to the camshaft. The rotating cup shaped part has a section of the OD removed to trigger the sensor. I believe the sensor straddles the OD of the cup. If these two aren't aligned, the cup could be contacting the sensor. I think you have to pull off everything down to the cam to get to the cup which if memory serves lies behind the cam pulley. I don't think there is any way for the cup to be anything but concentric with the camshaft. So, I'd look to see if you can adjust the location of the sensor to make sure it isn't "touching down" on the cup.

Knocking Sound from Engine after hall sensor replacement - billyblue360 - 10-04-2012

Thanks for the help guys. Will pull everything apart tomorrow. Did a blink test and got hall signal code. By pull off everything down to the cam, do you mean take the distributor off and other components off? I don't need to remove the timing belt do I? I can probably adjust the hall sensor with the clearance in the bolt holes as you suggest but how can i check? I can't see with the hall sensor on.

Knocking Sound from Engine after hall sensor replacement - MB968 - 10-05-2012

Hopefully with everything but the timing belt off, you'll be able to see the sensor, and at the window in the cup, be able to see enough to make any adjustment of the sensor to insure proper gap. I've never had the sensor out; is it possible to put it in upside down?

Knocking Sound from Engine after hall sensor replacement - SILVY968 - 10-05-2012

It may be that you have a corroded distributor mounting assembly and that the rotor is now scraping into the distributor cap. I had a similar experience, but it a rhythmic scraping sound, not knocking..

Good luck

Brian

Knocking Sound from Engine after hall sensor replacement - billyblue360 - 10-06-2012

Ok, so I got everything apart and took the hall sensor out. Not surprisingly it was broken exactly the same way as the original. A piece of the sensor had broken and was getting wedged in as the engine was turning. So I'm obviously going to need a new hall sensor again but how can I verify it's installed correctly? Do I have to take the cam sprocket off? If so, I think it would be a good time to replace the cam tensioner pads as I don't know if they have ever been done.

Also, when I turn the engine with the crankshaft, their is a slight resistance, then there is almost no resistance. Is this normal or should it always be the same?

Knocking Sound from Engine after hall sensor replacement - vliegwielolaf1234 - 10-06-2012

You feel more resistance when you turn the crank and the camshaft depreses a valve .

Is Normal .

But it should not take great force , different story with the sparkplugs still in then you build up pressure wich takes a lot more force and wil shoot thru after passing top dead center

Knocking Sound from Engine after hall sensor replacement - banditsc - 10-06-2012

The hall sender gets mounted with a little dowel pin locator, so there is only way it should really be able to mount. You can pull the distributor cover and see the sender thru the cam gear thru the holes as you rotate the crank. Do the two halves of the housing have any corrosion or bubbling?

Knocking Sound from Engine after hall sensor replacement - MB968 - 10-07-2012

Or, to build on banditsc's comment, is it possible that the locating pin is missing.

Knocking Sound from Engine after hall sensor replacement - banditsc - 10-07-2012

Maybe if the housing has started to corrode. That pin is in there pretty tight, had to swap it from my old housing to my new one.

Knocking Sound from Engine after hall sensor replacement - kwikt - 10-07-2012

I hope your cam gear assembly behind the distributor didn't come loose.