1999 Chevy Blazer

[quote:b7ae468bf9="reggide"]Engine Performance problem
1999 Chevy Blazer 6 cyl Two Wheel Drive Automatic 172,00 miles
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My 99 blazer was running fine one day and then the next it started missing when I would give it gas to accelerate. If you take it easy on the accelerator it will run 90 mph. but if you give it gas a little hard it bogs out and back fires, missess, and jerks. When you let off of it then you can get back in it easy and it will run. We have replaced the Distributor cap, rotar button, spark plugs, Air intake sensor, fuel filter, and battery. We bought a fuel pressure gauge and it showed it was okay but it was just checked at an idle and in park giving it gas. We have ordered a computer but it says on the receipt "must be flashed"-do you know what this means? Any other ideas on what could be wrong?
Thank you[/quote:b7ae468bf9]

Check the Timing. Back firing usually indicate timing problem.

Post responses here in forum....

we have done that too. the timing is great! we also hooked up a scanner to the computer but its not throwing any codes. The max air flow sensor is the other thing we repaced.

OK, Lets go back to the fuel pressure.....
You said you tested it and it was fine, Ok, Define Fine? Was the pressure 60 to 66 PSI ?

Check out this Video......

Testing Fuel Injection and Pressure Regulator System Video

https://www.2carpros.com/car_repair_video/test_fuel_injection_pressure.htm