I have a 94 Wrangler with a 2.5L 4banger. When you take off it boggs down for a bit then will rev up and take off ok. Since this started the fuel mileage has dropped drastically. I put new plugs and a cap and rotor on it and it made no differance at all. I have also ran some injector cleaner thru it. It does not seem to be missing, sounds pretty good actually. The Check Engine light is not on. I know a few people here have jeeps and am hoping somebody else has run into this problem allready.
I am thinking of trying to rig up a fuel pressure guage to screw onto the test fitting on the injector rail and see what the fuel pump is putting out. ( i allready changed the fuel filter). Does anybody know what kind of pressure should be there?? and what the timing should be set at??
btw-it is has a 5 speed manual tranny. Any thoughts would be appreciated.

 

I would suggest checking the pin voltage on the TPS......there could be a dead (flat) spot on it - quite common. This can cause all sorts of drivability problems and will affect mileage. Unfortunately, I can't tell you what the correct pin voltages should be for a 94 YJ but a little bit of searching on the net may help. Also, the mass air sensor is somewhat fragile and can get damaged easily......your best bet might be to get the Jeep hooked up to a scanner.....the scanner will give your TPS pin voltages and tell you if the mass air is in it's proper operating range.

 

ill try to find someone with a scanner. I wonder where that mass air sensor is located tho. I have changed the MAPS sensor and Oxygen sensor allready.

 

cats are common on those.

 

Mass air is located in the intake tube between the air filter box and the throttle body.

IMO, if the Jeep pulls fine up high but has a hiccup down low, it isn't likely to be a plugged cat as the problem.

 

i you already changed the O2 sensor, i (like TUGUM) would check the cat. converter, its probably plugged. check and see if your tailpipe is black.