Engine load?

I have a 98 Chevy Tracker 1.6 auto. My OBD reader shows engine load @ 25% in park at idle. Anyone have an idea what would cause this.

Read and enjoy. http://forums.trailvoy.com/archive/index.php/t-67697.html

The link was OK in regrads to explaining fuel trim and 02 sensor swing but I never made a connection to either your reported 25% load or the other OP’s reported 25% load. For me I would need a definition in “OBDII speak” just what is ment when “engine load” is referenced. It certainly can’t mean a load like what would be put on an engine during a horsepower rating test. I do wonder what context to view the statement “25% engine load”.

Both short term and long term fuel trim figures are neat to look at to gain an understanding on theory of operation of a fuel management system but they really have not been my main diagnostic tool, but then drivability was something I did when other work was not available or I was forced to (as in when a used car I was getting ready for sale would not pass emissions.

Perhaps short term and long term fuel trim codes come become more useful when you are going after a difficult to diagnois drivability problem or perhaps when a customer reports an unexplained mileage drop and really wants to investigate the cause.

The site referenced is one I have seen people turned away from when they post in the format that we get here (uninteligible).

Well let’s see? It’s four cylinder engine. At idle it’s operating the oil pump, the water pump, all the drive belts, and the torque converter. 25% load at idle is about right for that small of an engine. Have you tried reving the engine up to see what the reading is?


I suspect that it means that the air pressure in the intake manifold is 25% of the atmospheric pressure when the engine is idling.

I had this motor in my sidekick…and I agree, it’s normal as it’s a weak motor and doesn’t take much at idle. It needs lots of revs.