Topic: 1994 2.5L hesitating/cutting out

[jmcgill]

I recently got a 1994 YJ and the motor was neglected in terms of maintenance to say the least. I have been slowly bringing it back but canno seem to get rid of this bad hesitation that I get when accelerating between 2100 and 2600 RPMs. It starts out as a mild hesitation when I really push the throttle past half way. If I keep the pedal down it will get worse and eventually start to cut out like an old carbureted motor would do if it were struggling to get gas or the accelerator pump was bad.

I have put a new oxygen sensor, and throttle position sensor in. I have also cleaned out the throttle body and the idle air control valve.

Any ideas how I can remedy my situation?

Joe.

[sharpxmen]

check the spark plugs, wires, distributor/rotor.
check the fuel pressure.

[jmcgill]

The plugs and wires were recently changed by the last owner.  I'll check them again though.

[Rio_Grande]

I recently was having a similar problem that ended up being a corroded coil terminal and corroded wire connector.  Cleaned it up and all is better.

[dwtaylorpdx]

My 94 did that when the fuel pickup sock got plugged up... I replaced the pump while I was there since it had a90K on it.. :)


Dave

[jmcgill]

I had thought about the problem being in the fuel pump area. 

I think my current line of thinking is that it's in the injectors themselves.  I'm getting a pretty rapid bleed down in fuel pressure soon after shutting down, and my newly changed oil has a definite smell of gasoline.  It appears one or more of my injectors is leaking the pressurized fuel into the cylinder when I shut off. 

I have a set of the ford 19# ones in the mail right now, and hopefully they'll cure the issue.  If not, the tank is the next thing to hit.

[jfrabat]

I have had this happen to me twice; one time it was the fuel pump acting up (it would work fine on idle, but on acceleration, it would act up).  The second time is was a coil acting up.  Start checking the coil.  Sometimes water gets into the plug (the Jeep has the coil down low), and any rust in there will cause the engine to act up.  If I were you, I would replace the coil and wires to rule it out, but that's really up to you.  If it's not that, I would get a new pump.

[jmcgill]

The coil, plugs, and distributor cap/rotor have been replaced, so I will definitely be doing a fuel pressure test this weekend.

[tablesaw]

I have had similar problems and it turned out to be the fuel filter.

[dwtaylorpdx]

The coil, plugs, and distributor cap/rotor have been replaced, so I will definitely be doing a fuel pressure test this weekend.

The pressure test wont tell you the whole story (Been there done that fought it for 3 months...)
It will show the correct pressure, but under load and with some heat it cuts out... The pump gets intermittent
when it starts to wear out..

When I finally dropped the tank I found out the strainer screen was collapsing and
there was some sediment in the tank.

MIne started out being really rough at speed on hot days, and gradually got to where it would not pull.

Dave

[sharpxmen]

you check the pressure under load (driving), if there's no flow the pressure drops.

[Tr00b]

I sixth the fuel tank pickup screen being plugged.

Happened to mine in 2007 and caused similar probs. We tried the TPS, plugs wires cap rotor etc with no avail.