pi516

hey everyone I have a 93 grand Cherokee with the 5.2 in it, I just got it on the road last fall over the past 5 years I have rebuilt or replaced everything on it other then the motor tranny and transfer case. when I first picked it up it had a lot of problems but making the 4hour drive home my avg mpg was 23mpgs but now I got it back on the road and my avg mpgs have been around 7.5 to 9.5 mpgs. any ideas on what may be causing the bad mpgs?

Bustedback

Is the check engine light on?

SHELBYGT NSM

Is that what your overhead console is saying or is this what you have caculated?

pi516

no check engine light and that is what I calculated after my drive home when I got it and I recalculated it almost everytime I fill it up with gas. it seems to do better the colder it is outside for some reason

zeecherokeeman

Get a free scan at local auto store.

odgreen

.....93..... parts stores can't scan an obd1

Bustedback

Key on, key off, key on, key off, key on and then count the flashes of the check engine light.

odgreen

This^

zeecherokeeman

CLEAN THROTTLE BODY,REPLACE OXYGEN SENSOR, CHECK ALL SENSORS (iat,map,tps)REPLACE FUEL FILTER...Should be plugin on firewall DRIVER SIDE(AT LEAST ON 94 SHADOW)get a smart person OBD1 ....

Bustedback

The data plug is on the passenger side firewall.