After changing the timing cover and chain,and gasket my engine now runs rough.We double checked the marks on the timing gears and chain they are where they are supposed to be. we also replaced the crankshaft sensor,plugs and wires.We timed it to tds#4 like the hayes book said. Is this correct? Also do you set the rotor on the dist. to the number on the top of the dist. or to the pin on the inside of the dist. that lines up with that number.

 

Have you tried reading this post?

https://blazerforum.com/forum/tech-a...-timing-24373/

Very helpful for setting your initial timing when you replace or remove the distributor.

 

how do I read the post

 

You will also have to do a crankcase relearn since you replaced the sensor.

 

jim1, what I meant by reading the post was to compare what your repair manual says (which has been known to be wrong) with what the write up says you should do in order to time your engine correctly.

I would start reading the post from the very beginning. It will help you set your initial timing correctly. Then, as 50lb_cat said, you'll need do what the very last statement says to do in the write-up. Most shops should be able to do this very simple procedure for you. And, it shouldn't cost that much either.

 

You read it by clicking on the red link