[neilyg]

On Saturday my Forester started and then shut down. On trying to restart it cranked but did not start. The cranking sounded very free as if there was no compression which led to suspecting that the timing belt had broken. The belt was inspected and was intact, timing marks were all aligned.
Bent valve has been suspected, but a bent valve usually occurs when the timing belt breaks and the timing is out.
What could be possible cause for this problem.

 

[2003suby]

On Saturday my Forester started and then shut down. On trying to restart it cranked but did not start. The cranking sounded very free as if there was no compression which led to suspecting that the timing belt had broken. The belt was inspected and was intact, timing marks were all aligned.
Bent valve has been suspected, but a bent valve usually occurs when the timing belt breaks and the timing is out.
What could be possible cause for this problem.

how old is the timing belt ... possible extremely stretched t-belt ... still lined up and intact but so stretched that the timing is out far enough to act as if the timing belt is a tooth or two off ?

what the year and model of your foz ?

 

[neilyg]

Car is a JDM 2006 Cross Sports . Gone 34000 km.

 

[2003suby]

hmmm

I go down the simple list first

got spark at all cyl ? maybe a coil gone off .. blown plug ...

got fuel to cyl

possible clogged fuel filter ... or injector ... was there a recall for the fuel valve on MY06 ?

 

[funkymonkey1002]

Is the engine actually turning over or is the starter just spinning?

 

[2003suby]

Is the engine actually turning over or is the starter just spinning?

you know what I read it as it was trying to turn over .. good question

 

[neilyg]

Is the engine actually turning over or is the starter just spinning?

Engine turns over

 

[neilyg]

hmmm

I go down the simple list first

got spark at all cyl ? maybe a coil gone off .. blown plug ...

got fuel to cyl

possible clogged fuel filter ... or injector ... was there a recall for the fuel valve on MY06 ?

Engine is turning over very freely, no resistance/compression

 

[ferret]

I see you stated the timing marks were all aligned, did you just check the cams? or also the crankshaft? Remember the crankshaft uses the small scribed line on one of the sensor flags.

There have been instances where the timing belt has jumped at the crank sprocket only.

If all are aligned, I would check for spark. If there is none then suspect the cam sensor or crank sensor. When I saw a bad crank sensor, the engine turned as if no compression. After replacement, it started right up.

 

[bonevvladimir]

Confirm the lack of compression through compression test and if there isn't any, check if the timing belt sprockets haven't somehow slipped on the crankshaft, camshafts

 

[neilyg]

I see you stated the timing marks were all aligned, did you just check the cams? or also the crankshaft? Remember the crankshaft uses the small scribed line on one of the sensor flags.

There have been instances where the timing belt has jumped at the crank sprocket only.

If all are aligned, I would check for spark. If there is none then suspect the cam sensor or crank sensor. When I saw a bad crank sensor, the engine turned as if no compression. After replacement, it started right up.

Will try and let you know.