I've got a '91 YJ Islander, 4-cyl, 5 speed.
Has been running fine, but all of a sudden I go to start it and I can't get over 25km/h.
The only thing I can think of that I did differently is that I put fuel injector cleaner into the fuel in the last fill...but that was 140km ago.
Also there is a hissing/grinding? sound comming from the exaust pipe area. Seems to get louder when reving the engine.
The acceleration problem happens whether moving or in neutral. Last night it took me an hour to drive home about 5 blocks! Had to keep reving then letting out the clutch.
wrong, wrong, wrong. A small cat has climbed into your engine via the exhaust pipe. The engine noise and heat is pissing him off, thus the hissing. I suggest laying a trail of kitty treats from the exhaust straight into your big loving arms, you old bully.
[ " The acceleration problem happens whether moving or in neutral."]
ok,...I see how it can be hard to accelerate in neutral.
but honestly i had a prob like that and it was due to a faulty Ignition Control Module,..but then again that is for a 88 carbed 258,
Definitely a catalytic converter problem. Most likely the inner material has broken up and clogged the pipe.
It's a jeep thing, I do understand!! 89 YJ Laredo,4.2L carburated. Chrome bumpers and grill. 31 AT's on 9x15 chrome modulars. Mustang GT buckets. 3" body lift and 1 1/2" shackle lift. Completely emission & computer free. Runs great!! Took the shackle lift out, they suck!!
Soon to be SOA with 35's
I have the same problem with my 1994 YJ 4cyl. However I don't have the hissing problem, just the acceleration problem. I replaced the Ignition control module, but that didn't solve the problem. The only other option was that the ECU was at fault...it comes in today, so hopefully that will solve my problem...
Based on the fact that yours has the hissing sound, I'd go for the catalytic conv. over the ECU though.
1994 YJ, 2" body lift, 33" BFG's, 4-banger.
I had a similar problem with my 94 yj. Acceleration was bad and the jeep rumbled. I had bad fuel injectors and got a new one and got the other 3 cleaned and a new fuel line. It was all rusted out. If this is the case, fuel injector cleaner wont help until after u get them cleaned or replaced. Runs fine now except for at high speeds I need to look into that problem.
'94 YJ 4cyl. 5-Speed, Stock but not for long.