92 cherokee laredo terrible gas mileage

[heuer007]

Hi, first post. Just inhereted a 92 jeep cherokee laredo from my dad who just bought a BMW 530i. Now my dad is not the type of guy that goes for a tune up every 10,000K. Anyways the gas mileage is absolutly absurd. I am trying to sell it but until then im stuck with it. Id say that I put in around 20$CDN every 2 days and I drive about 30 mins a day. My question is what is the best way(s) to improve fuel economy without spending big dollars? My friend told me to get new spark plugs, but I know practically nothing about cars. MUCH APPRECIATED

[JDPascal]

Plugs and Air filter first of all.

Then plug wires, distributer cap and rotor if you need it.

Don't forget tire pressures.... Keep mine even all the way around at 32-36 psi range....

Just the first things that come to mind right now....

any one else think of anything else....?

JD

[heuer007]

when u say plugs u mean spark plugs? and Im assuming plug wires is spark plug wires? and what the hell is a rotor?

[heuer007]

i should also note the jeep does have the common problem of leaking oil which is quite common for that years model.

[JDPascal]

You got it on the plugs and plug wires.

The rotor is the part in the top of the distributor under the distributor cap that distributes the spark to the cylinders in the firing order rotation.

It has a contact in the center where the coil delivers the spark and a contact point at the circumference where the spark jumps to the contact in the distributor cap.

The contacts where the spark jumps build up a deposit and the spark also erodes the edge of the contact and requires more voltage to get through so you replace the cap and rotor.

Sometimes I've been able to clean the deposits away and lightly file the contact edges sharp again to get buy for a while.

JD

[viper1861]

Take a sledge hammer and carefully hammer the cherokee's square box figure until it resembles a wedge shaped design. If it still runs you will probably get better gas mileage.

[IdahoJeeper]

Hi there! Just had a similar problem try this...

http://www.automotiveforums.com/vbul...d.php?t=280093

After all was done, I went from 15mpg to 20mpg... I'm planning on keeping my Jeep, so I have other things planned (exhaust, air intake) which will help also.

[cherokee_guy82]

the oil leak is most likely from the rear main seal... look underneath and see if the covers between the engine and trans are coated with oil, if so, make sure that the valve cover is also not the cause. if it is the rear main, mine has the same problem, and on '92 and newer, the seal is two pieces, whereas the '91 and older is more commonly a single piece which means the transmission and transfer case have to come off the back of the engine to replace. the two piece (which mine is) can be removed by taking the oil pan off

[kmerian]

I was able to improve the gas mileage in my 89 Cherokee with a tune-up and replacing the fuel filter, went from about 11 to 20 mpg.

[Saudade]

If it is the rear main seal, this could be expensive for you. Mine leaked ('88) but I was able to change it myself for only the cost of the seal (mine was 2 piece) and oil pan gasket (under $20 US). However, it was a very dirty job and removing the pan was very difficult.

As far as your mileage, as others have suggested, a good tune up is the place to start.