1997 Chevy Blazer Acceleration problems

SAQATRECE

MEMBER
1997 CHEVROLET BLAZER

Engine Performance problem
1997 Chevy Blazer 6 cyl Two Wheel Drive Automatic

I recieved a response to my earlier posting of the problem I am having with my 1997 Chevy S-10 Blazer. You asked for the specific trouble codes that came up. After runnig the vehicle for a while some of the codes returned, they are PO108 (MAP sensor high output), PO420 (catalyst system efficiency below threshhold on bank 1) and PO507 (Idle control system, RPM higher than expected). This is the first time that PO108 has come up, this may be due to having run the vehicle without the breather attached for a few minutes. I was having one other code that refered to the Idle air control but I replaced the vacuum hose and that code did not return. Just as a reminder, my problem is the vehicle wiil only accelerate if the pedal is lightly pushed, very much acceleration and the engine just bogs. I checked the gas cap and it seems okay but the problem does get worse with the cap removed. I am going to purchase a fuel pressure tester and check pressure to the rail and am dropping the tank to check ground. Thanks again for your assistance.

2 Replies

KERENSELF

MEMBER
54 POSTS

Just a footnote, lack of power during acceleration, or "bogging down" can definitely be caused by a bad catalytic converter. The most accurate way to have this checked is for a shop with a five-gas analyzer to check the exhaust emissions.
Then there's the shade- tree way :) if you know anyone who has an infrared thermometer (HVAC heating and air technicians usually) checking the exhaust pipe temp going INTO the converter and comparing it to the temp of the pipe coming OUT of the converter can give you a general idea. The temps should be reasonably close. If the output temp is significantly lower than the input, odds are your converter needs to be replaced.(They also sometimes give off a bad smell.)