Ever hear of a CPS skipping several teeth?

[GrimJack]

Odd thing happened to me today, I was driving along normally, in traffic in the city, so just cruising, and the engine dies. I try to restart it, and it doesn't want to fire - the engine feels like the timing is way off.

So, I push it across the street and around a corner. Quite the workout, I might add! Pull out the toolkit and start trying to track down what went wrong.

I check the timing belt, and it's still there and in one piece. Then I put a wrench on the main pulley and crank the engine around to TDC, then pull the timing belt cover back enough to verify that the cams are still aligned, on the theory that they might have skipped a tooth or six on the belt. No problems yet.

So I pull the CPS... which I figure should be either aligned, or 180 out... and it's at like 90 out. I re align it, put it back in, and it fires up no problem.

So I'm left thinking... wtf?

 

[johnathan1]

That's really strange...maybe one of the two gears are worn out? Or maybe the CPS mounting bolt lost torque and backed out?

 

[starscream5000]

Did you inspect the CPS when you took it out?

 

[IJ.]

Can't see how it could happen Dave..

Is the pin still in the CPS shaft?

 

[suprahooked]

IJ got it thats exacty what i was thinking, Sounds like the pin sheared in half . But he beat me to it .LOL

 

[Facime]

yes as I was read I thought the same thing. The pin sheared on the drive gear. I suspect your fix wouldnt last very long as it will just rotate again.

 

[GrimJack]

Seemed fine when I took it out. I put it back in and it's driven 75 km since without problems. The gear on the CPS was fine. I didn't check the gear on the cam yet, but I'll be surprised if it's mangled.

I'm going to pull it again and check the pin just because.

 

[suprahooked]

Well how is that pin? Let us know.

 

[Adjuster]

Sheared pin.....

Going once...
Going twice...
Going three times....

Sold!

(I'm not a betting man, but it's about the only option from what you described.)

The gear, shaft and of course, the gears on the cam might be fine. Just need a new pin? (I wonder if tool steel, or the end of a correct diameter drill bit would work, or if it would be too brittle?)

Just thinking out loud in the cheapest way to fix thought pattern...

 

[Jaguar_5]

Have you seen the thread about rebuilding your cps?

 

[3p141592654]

I can't see the pin shearing off unless the bearing seized solid. Its a 4mm steel pin! I would check the press fit of the top reluctor on the slim chance it is loose and rotated. Otherwise, I think the gear itself jumped relative to the cam. Possibly due to a worn bushing on the CPS, which is another thing I would check. The fact that it is still working though is really strange.

 

[GrimJack]

Pulled it out today, half in the rain, half in the sun.

The pin is fine, so is the reluctor fit. Next step is to pull the valve cover and see if the end of the cam is ok, I guess.