PT- Does "Service Engine" light have to be on???

Does it have to be on to leave a code for a possible reason for very
bad mpg? Usually 16 in city, 15 with AC on, now down to 13 with AC on.
New plugs, clean air filter, correct tire pressure, all things done as
suggested in this group. Just about 40K on it.
I'm taking it in for PA state inspections and I asked them to see if
there's a code in the computer for the bad mpg. They said that if the
Check Engine light didn't come on, there will be no code.
True??

 

True. With the a/c running you will not get as good fuel economy as you
would if it were off.

Glenn Beasley
Chrysler Tech

 

<SNIPPED FOR BREVITY>

Usually 16 in city, 15 with AC on, now down to 13 with AC on.

____Reply Separator_____

I know this Glenn, but in my original post I did say that I was getting
15 mpg with the AC on, and now it's down to 13. Plus, I've had some "so
called" engine maintenance done.

 

There really isn't much maintenence on that vehicle that could cause a
problem if it wasn't done right except maybe a plug gap not correct but then
I would think that the OBD2 system would pick it up and set the check engine
lite on. There are monitors on that vehicle that PA's Emission Program will
check when you go thru emissions. If one of those monitors has not passed
they will let you know.

Glenn

 

how is the alignment after 40 k, it might cause some rolling resistance if
it is off
are the brakes dragging?well known wheel bearing issues with the pt,any
growling at highway speeds? does it coast easy?? can you push it easy in
neutral
what about your speed! to truly save gas drive 55 and see how much you save!
the pcm - the cars computer- has a setting called pinion factor and it
relates to tire size .and it can affect fuel management if it does not have
the correct tire size programed into it
if we the people work on ways to cut gas usage,
it will create a gas glut at the refiners and they will have no choice but to
lower prices
so it's moves stored fuel and since there is seasonal blends of fuel now and
it would cost the refiners a arm and leg to reformulate it. they would
rather sell it
and since they can't store it as long and have no place to store it like
they used to since they closed some refineries. prices will go down!


remember beanie babies!you could not find them cheap when the came out and
now you can't give them away. the same supply and demand can apply, cut
demand supply goes up and price will go down