So i hydro locked my engine in my 98 4.3 litre blazer. Couldnt get it to turn over must of bent somethng. Picked up another 4.3l out of a 97 jimmy/blazer from a auto wrecker not sure on the engine code. New engine is in and no start. I have 60 psi fuel pressure. I have spark at all 6 cylinders. I have 125/130psi compression in all cylinders. Check engine light is on but my scan tool says no codes present. What else should i check? If i have a x code engine now do i need to reflash ecu?

 

Check and make sure the ignition timing is correct. You have to do a CPS relearn to get the correct information the the PCM. Check for blown fuses in the engine bay. There can be a ton of things that go wrong with engine swaps. Does it fire if you spray ether down the intake tube?

 

I was under the impression the timing is comtrolled by the ecu only, i also pulled the crank sensor from my old engine and put it in the swapped motor. I can get the engine to stumble but not fire with starting fluid. But it does seem to be out of time. Is there a way to manually adjust the timing.

 

As far as I know, anytime the CPS is removed, a re-learn must be done. Timing is controlled by the computer, but the distributor could still be out of time. A scan tool would definitely be required to get running 100% correctly. There are plenty of threads discussing distributor timing and the works. You cannot rotate the distributor, if thats what you are asking. You need to remove the distributor and turn the rotor inside to "manually" time it.

 

Try flipping the cap the only other way it can go (180° around) if you timed it yourself then you have a 50/50 chance of getting it right or 180° off unless you looked at which valve closed before TDC. Just did this to my neighbors 4.3 and it wouldn't start until we figured out the cap, even put in a new CPS and it WILL run fine with a new CPS just get the relearn done soon

 

So i finally got around to finding tdc on cylinder one and check the rotor it was pointing at the #1 position. Still no start. Any other ideas.

 

are all the grounds connected to the block?
when i did my stang engine swap i had a similar problem, finally figured it was the block not being grounded well. i installed a new grounding strap and she fired up.

 

As others have said, it sounds like you're 180 degrees off on your distributor. Remember each piston goes to TDC twice in one rotation of the distributor.

 

Cylinder 1 was on its compression stoke when i checked the rotor was pointing to cylinder 1 if i was to pull distributor and rotate 180 it would be pointed at cylinder 5.

Hooked up grounds one on the back of each head. And the main ground strap also. Pretty sure all grounds and connectors are connected correctly.

Still have a check engine loght on but no codes. Have a 200 dollar scan tool maybe need to trailer it to gm to see what pops up.