My car ran perfectly fine but it was time for it's first timing belt change. After changing the belt and water pump (which took some effort as it was my first time) and adjusting the valve clearances and putting new coolant (Honda blue).

Now the car runs terrible. Car will not accelerate at all, to get to 20 mph might take 20 seconds. There is something wrong.

I attempted to adjust the low idle with the screw on the idle valve but to no avail. I also noticed some water out of the tailpipe, but I would be hard pressed to believe it could be a blown head gasket, this car ran perfectly fine before the timing belt change.

2000 Honda Civic EX - D16Y8 engine - 4speed automatic transmission.

Any ideas?

 

You didn't set timing correctly. Check your mechanical timing.

 

 

Water out the tailpipe is normal as its a byproduct of combustion. Now if it smells sweet like coolant then you have an issue.

But my vote is the same as the prior responses. That should let you know if you installed the belt incorrectly.

 

Is it possible I moved the camshaft or crankshaft while the belt was off? Guess I need to go ahead and tear it town again to check.

Question, do I need to check the valve clearances again if it does turn out that the mechanical timing was off?

 

Your response already indicates you didn't verify mechanical timing at all but yes it's very possible. It's also possible that you didn't tension the belt properly. Can you eleaborate a bit as to how you did everything step by step?

As for valve clearance, it's completely independent of mechanical timing.

 

I will admit I didn't verify mechanical timing as described but I did the whole 'make marks on old timing belt, transfer marks to new timing belt, match marks onto TDC indicators on car.'

I followed the Helms manual for setting belt tension. Belt rotated several times, bring back to TDC. Loosen tension adjusting bolt, rotate crankshaft counter-clockwise so 3 teeth move on camshaft, re-tighten bolt.

 

That's such a stupid way to do it, and I have no idea why people still do that ****. There are clear markers on the cam gear, and clear markers on both the timing gear, as well as the pulley. Pop your valve cover off again, and make sure things are lined up. I promise you they aren't.

 

Shouldn't come to a surprise to anyone but yes the mechanical timing was off. Lesson learned. Valve adjustment had to be redone because they were adjusted when the pistons were not at true TDC.

How critical would it be to acquire a timing light to check the ignition timing at this point?

 

Very

 

Ditto

 

How critical would it be to properly set ignition timing? Come on man, that thought shouldn't even cross your mind. Don't halfass your car. Do it right, or you'll be doing it again soon.

 

Just checking. None of the videos or DIY instructionals mentioned anything about checking ignition timing.