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Simple questions with a long explanation:
Would my 1.8 run smoothly (with a lack of power) if the timing belt alignment was 1 off on the crank by 1 tooth?
Would it run this way if 1 of the electrical connections was dirty/ going bad?


I changed my belt, pulleys, tensioner, crank seal, accessory belts, bearings.. etc. when the belt broke. When aligning the timing, the cams were right on, but the crank would be off 1/2 tooth either way. I set it to what looked closest, and cranked it 4 times over, and it was the same.. The car runs smooth, but feels like I'm pulling a trailor, or have bad gas (which is also possible, even though the gas was not old), so I ran it down to a half of a tank ~from being full~ and added new gas, with no improvement. Also, with it being that close, would the CEL come on? (It hasn't).
Or maybe it's something completely different that I screwed up in the process..
I'll report back when I have a full tank of new gas.

IIRC, if the timing is off by one tooth then it will not run that great at all, I would fix that before something gets messed up.

Yes your engine could still run smoothly even with the timing off. If the intake cam timing is too far advanced over the crank timing.. the valves would close before a full intake stroke was achieved. This would result in less air/fuel mixture in the combustion chamber during the combustion stroke. The engine would also be running a bit rich since the amount of fuel being injected would be greater than the amount of air being drawn into the cylinder and that would be detected by the O2 sensors so then the ECU would advance the timing even further (until the knock sensor detects pinging) which would worsen the condition. Also.. just to complete the picture.. the same can be happening with the exaust valves opening too soon.. though this usually results in popping or backfiring.

This would be fairly easy to check for.. do a compression check on the engine. Stock decent condition K8 engines should be in the 170-180 range. If you find that all 3 cylinders of either bank (or both banks if its the crank timing thats off) are down in the 150-160 ranger or lower, that would be a sure indicator that your valve timing is off by a tooth or more.

Tunes67

fowljesse wrote:Simple questions with a long explanation:
Would my 1.8 run smoothly (with a lack of power) if the timing belt alignment was 1 off on the crank by 1 tooth?

I noticed this when I put my belt back on the klze... it was off by 1/2 a tooth either way... I have actually noticed more power so it makes me wonder if it was off 1/2 a tooth running richer before and by me changing it, it's running leaner...

Thank you very much! I'll do the compression test.
So, it won't show the #4 or #5 code if it's that close?

Nope.. in fact it wont throw any codes that will reveal a timing belt issue. You might get a cam or crank position sensor code at the moment that the belt breaks.. but that would be it. It wouldnt come back after the ECU was reset as long as both the cam and crank are actually spinning.. those sensors are happy.

Tunes67

If it's off by a tooth, it'll tend to be smooth but sluggish.
It an ignition related wire somewhere is wrong or unplugged, it'll studder.

also if timing is off, it will backfire at really high rpms.. well that was my case.