Chevy Blazer Misfire After Intake Manifold Gaskets Replaced

Question:
I recently replaced intake gaskets and all gaskets with intake (throttle body, distributor, upper and lower intake). When I started the Blazer idle was fine, I revved the engine and still seemed fine. I went for a drive and after reaching operating temperature the engine would not rev up. If you rev slowly you can rev fine, if you rev fast will not take fuel and sounds like popping through air cleaner. The check engine light came on and showed bank 1 and bank 2 O2 sensors low voltage. Got any ideas? 1998 Chevy Blazer. Replaced intake gaskets.

Answer:
You may have gotten some debre on the sensors while doing the work. Plug wires not in the correct firing order. Vacuum leak. May have left something unplugged or blew a fuse. Low fuel pressure would also cause this. Possible timing chain jumped time, or distributor not in exact same location as previous.

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Question:
Truck cranks will not start. Getting fuel and spark. Set the crank to 0 degrees. Pulled distributor cap and button is pointing at #1. When cranking and I step on the gas and it pops through the TBI. Need some help. I'm thinking stretched timing chain? 1991 Chevy Blazer Engine= 350 Repairs= new pick up coil, spark plugs.

Answer:
This could be a stretched timing chain, or it may have jumped a tooth. Usually if it has done that, the distributor rotor would not be pointing quite at number 1 cylinder when it should be. You need to turn the crank using a ratchet and atch the rotor turn. If there is no movement for about 3-4 degrees then the nchain is stretched.

Your Blaer also could have a flat cam, or worn lifters, or both. The older trucks were known for that at times. You say engine is getting fuel, but make sure you have proper fuel pressure. It should be around 10-13psi. A clogged fuel filter can cause low pressure and low volume, so check that too.

Also, if you have a plugged catalytic converter, that can cause popping and backfiring since the exhaust pressure has no where to go. Could be a broken distributor, too. I'd start with the easy stuff to check first like fuel pressure, etc, and go from there.

Question:
Got the Blazer about 2 weeks ago. Was sitting for about 4 months. Anyway at the beginning i had no acceleration if i tried to accelerate it would bog out and make popping sounds out the muffler so first thing i did was change oil. Oil filter. Air filter, plugs, wires ,cap and rotor. It improve about 20 percent meaning it has some acceleration but if i try to force it a little more i still here the popping sound out the tail pipe and still bogs out. It has 188k miles on it dont no much about the truck. 1992 Chevy Silverado Blazer. Complete tune up.

Answer:
You could possibly have a clogged fuel filter that is limiting the amount of gas the engine is getting, and causing it to bog down. Also, if the vehicle has sat for an extended period of time, the gasoline that was in it has probably turned bad and separated.

You might want to run a few tanks of premium through it to see if that helps. Another possibility is a catalytic converter that is coming apart internally, or blocked up with deposits. That would cause a bad hesitation and popping when trying to accelerate. You may want to check timing and make sure it is set correctly. I believe your vehicle should be at 0 degrees at warm idle. Quite a few things to check, I'd start with the easiest like changing the fuel filter, putting good gas in it, etc.


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