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Q: Car wont start after replacing timing belt but I know timing is spot on. What could it be?

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After replacing the timing belt, water pump, cam and crank seals, valve cover gaskets the car wont start. It cranks and tries to sputter and start but just wont do it. I have checked the timing over and over and find all the marks lining up every time. I have checked for spark from all plugs, wires and coil packs but they are ok. I have also tried taking the throttle bottle and intake tube off to see if I have missed and wire connectors and I cant seem to find any anywhere that I missed. Is it possible something else went bad just out of nowhere? It drove into the shop just fine right before I started the job. PCV valve is broken off and not connected, would that cause it to not start, because I dont think that would affect it that way. Any and all advice is greatly accepted and appreciated.

My car has 150000 miles.
My car has an automatic transmission.

Hi there, thanks for writing in.

Well if the car ran before you did the timing belt, but now doesn’t run after, I am or course going to say that the likely scenario is that the timing is off. Make double and triple sure that you’re using the correct marks on the camshafts and crankshaft, and make sure that the belt is properly tensioned. If all this is correct, it’s not impossible that something else failed, just highly unlikely. The next step after verifying the timing is correct would be to check fuel pressure and run a compression check. You would normally want to check for spark, but you have already done that. If the timing belt was off before and you turned it over at all, it could have damaged valves and that would cause the motor to have no compression. If these checks don’t yield any results, then you should consider contacting a professional technician, such as one available from YourMechanic, to diagnose the no start condition.

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