Mechanics

CHEVY REBUILT ENGINE MULTIPLE OR RANDOM MISF

1998 Chevrolet Silverado

Engine Mechanical problem
1998 Chevy Silverado V8 Four Wheel Drive Automatic 130000 miles

1998 Chevy k1500 350 129000 miles

I recently rebuilt this engine and did all the mechanical work myself. I had a very experienced guy do the block work, and he put a new crank in it. I kept the same cam and heads. The mechanic that did the block said the cam was alright, and the heads/valves appeared alright to myself and several others. After several hassles and tinkering I am to the point where the engine will run but brings up the po300 trouble code, twice. I have been through the ignition system several times, and everything appears fine. I have no compression tester, and did the valves according to a haynes manual. What next? I am getting limited on what I can do myself and dont wanna go broke at the shop. Any suggestions?
Avatar
Evan Tyrrell
March 5, 2010.




Other than the misfire codes I have been getting o2 sensor codes since before the rebuild. After the rebuild I got an additional code for the o2 heater sensor, I believe on bank one. Today I tried unhooking the map and maf sensor, It didnt seem to have any effect on the motor.

Tiny
Evantyrrell
Mar 5, 2010.
Parameter Description Value
DTC for which Freeze Frame was Stored P0300
Fuel System 1 Status Open Loop
Fuel System 2 Status Open Loop
Calculated LOAD Value 26.67 %
Engine Coolant Temp 80.60 °F
Short Term Fuel Trim - Bank 1 0.00 %
Long Term Fuel Trim - Bank 1 0.00 %
Short Term Fuel Trim - Bank 2 0.00 %
Long Term Fuel Trim - Bank 2 0.00 %
Intake Manifold Absolute Pressure 20.73 inHg
Engine RPM 2,544.50 rpm
Vehicle Speed Sensor 0.00 mph
Air Flow Rate Mass Air Flow Sensor 7.78 lb/min
Absolute Throttle Position 29.02 %

idk if this helps

Tiny
Evan Tyrrell
Mar 5, 2010.
Hi, Thanks for using 2CarPros. Com. I wanted to see where your at with your problem and see if was any additional information we could help you with. I f so please let us know, Thanks again.
AD

Tiny
2CarPros Linsey
Mar 12, 2010.

AD