EEVEE

Dang it hit 233 miles before i chickened out and filled up with gas as my gauge is a troll at times and loves to tell me i have a quarter left then boop goes under the red e line. But yeah next is my exhaust system it needs work and sure my cat is getting close to clogged as when i shut it off i hear like pressure from the upper parts of the exhaust and im guessing thats before the cat its doing that as i restart it again and shut it off it doesnt do it.

'90Cherokee

How many gallons did it take to re-fill?

'90Cherokee

There's no way your cat is clogged enough to hear pressure after you shut it off, the engine wouldn't run with that much of a clog. You're probably hearing the A/C system depressurizing or maybe hearing a vacuum leak refilling the reservoir.

EEVEE

i dont know i just gave enough gas to get me by.... And this is with the ac off. Also i didnt do a vacuum leak test yet maybe since its cooler i can do it now. What hose should i use? I was just gonna use a cigarette and blow smoke through the hoses.

s346k

highly doubt it's a clogged cat. my xj wouldn't rev over 4k and had a noticeable loss of power when the cat was bad. vacuum gauge confirmed.

EEVEE

Ugh wish i can get this issue sorted out lol. May need to get a vacuum gauge and see whats up then.

'90Cherokee

Or maybe just see what MPG you're actually getting from it to see if there's actually a problem or not. 233 miles from 3/4 tank wouldn't indicate a problem.

EEVEE

ok so right when my gas gauge went under the e line it hit 270 miles, i filled it back up to where it was and took 20 gallons so i calculated it and am getting 13 mpg but i also notice my ac uses alot of gas because i only used it for like 2 days and my gauge dipped quickly when i did. But now i hit 60 miles today and the gauge didnt even budge yet so could it be my ac system?

Bugout4x4

AC can greatly reduce your mileage, because not only is the pump adding load, the fans are kicking in more adding load also.

'90Cherokee

"filled it back up to where it was" Does that mean full 'till the pump shut off, or you put 20 gal. in and the needle was about where it was last time you fueled?

Is it stock height and tire size?

Depending on the driving done 13 might be good or a bit low.

Anony

That's approx. what I get on my 98 and my AC was removed. 235 All Terrain tires and ~2 - 2.5" OME lift.

I replaced the exhaust a while back all new exhaust parts including new cat and new OS sensors. Performed tuneup with new plugs, dist cap / rotor and plug wires.

Engine with ~200,000 miles runs just fine, only I need to keep filling it up, sooner than it's epa rating.

Once in a while travel in heavy ocean beach sand, which I had been contributing to the poor gas mileage.

Perhaps I should check the gas mileage more closely with pavement only driving, but currently getting worse mileage than some people I know who drive larger pickups ~150s and ~250s, possibly larger both gas and diesel, supercharged, etc.

EEVEE

Back to the top of the neck almost overflowing and thats how i can really judge because sometimes the pump stops all the time after i usually put 10 gallons of gas in when its empty. And i would of just suspected a little more range 100 miles seems like alot to lose in just ac.

Ralph77

I don't drive much so normally my gas mileage kinda sucks. Thinking I average about 14 MPG around town. You have to realize I live a 1/2 mile from work but go out of my way a bit. I have these routes so that by the time I pull in the parking lot the thremostat has opened. But I did take a trip to Jersey awhile back to pick up some parts. 340 mile round trip. Mostly highway. Heavy rains that day but was able to use the cruise control for most of the trip out there. Way back traffic was heavier and there was a couple minor fender benders causing some traffic snarls. Couldn't really use the cruise control on the return trip. So my overhead console said I was getting just under 21 MPG. That pretty much goes with my calculations. Longest single trip I ever took with the Jeep. By the way. '00 with CA Emissions. Pretty new exhaust. Front cat back. Replaced all 4 O2 sensors. Relatively fresh plugs. Stock height and tires. 4 hole injector upgrade sometime ago. I have added a little weight to the Jeep to in the form of skid plates, running boards, and a driver's side power seat. Thinking the roof rack, running boards, and rear mudflaps are not helping too.

EEVEE

Lucky you have cruise lol that would be a godsend for me, But maybe im overthinking it it just seems like a dramatic loss with ac.

Ralph77

I added the cruise control. The Jeep did not come with it. Probably the easiest upgrade I have done as far as all the factory options I have been installing on the Jeep. Yours is a '99? Get switches from a '99 to '01. Get the clock spring and actuator from a '97 to '01. The little wiring harness for the switches I am not sure if it has to be '99 to '01 or if '97 to '01 will be fine. Steering wheel loaner tool and make sure that the wheels are straight in the Jeep you pull the parts from and when you install it in yours. It is literal plug and play.