flashing CEL after timing belt snap
 

Hey the check engine light on my 2000 hyundai accent started flashing today.

The timing belt snapped at low speed idle in the driveway when I started it, but I replaced the timing belt and set the timing all to TDC and it runs but quite poorly.

The idle is rough, but it starts and goes and has plenty of power. Nothing feels wrong but it runs rough and the check engine light flashes sporadically.
It blinks at a constant rate but then goes off for a few minutes, then comes on again flashing.

There are no accidents, the car has always ran well. No problems, until now with usual maintenance the belt snapped at like 96,000 miles, and I fixed it all properly.

Any idea why my CEL would be flashing after the timing belt being replaced? Thanks so much!

It's an interference engine. When the belt broke you probably bent a few valves.

If you're sure you got the sprocket set correctly when you reattached the belt, then Nova is right, you've got serious engine damage. New motor time. Visit car-part.com for a motor from a junkyard in your area.

thanks for the words..

That sucks, new motor time. I don't doubt it's got bent valves, that would make perfect sense to me. As far as I know it was all set to top dead center and put back together correctly. If the timing was off, it would run poorly but the CEL wouldn't come on.

As an aside, how do you know it's TDC? There were two white marks on the camshaft pulley, I positioned the one straight up and the other straight forward like an L -- and on the crankshaft pulley there was a little notch in the pulley (which I positioned straight up) and the key in the crankshaft I positioned straight forward. (Like an L)

Assuming the timing isn't off and I did bend valves, why would that be new motor time? The belt snapped at low speed and low RPM so I don't think there's any really serious damage to the pistons or cylinders. I know you can buy valvespring compressors and on my honda you can get new valves/springs/retainers and put them in yourself. Does it sound like I'm going to be changing valves? Thanks so much!

Sounds to me like you got the sprockets wrong. If you got the sprockets wrong, it would produce a CEL. It's not something you can just throw in there and expect it to work, you needed a diagram. Since your car was idling at your house when the belt broke, you could expect it to survive.

Excellent, so incorrect timing could make it show the CEL.. I put my code reader on it the other day and it threw 3 codes at me. (Generic general misfire, misfire cylinder 1, misfire cylinder 2) -- I replaced the plugs and wires but it still runs poorly at idle. It seems like it's misfiring at idle only, because when the car is driving there is plenty of power and it doesn't seem to be misfiring.

I considered it being the coils, but cylinder 1 and 2 are operated by different coils, so it would mean that both coils are bad and that's a lot of money.

I will reset the cam timing, and try adjusting valve lash for the valve rocker arms. I'll post again after fixing these 2 things and hopefully my CEL will stop coming on.

Thanks!