Topic: So my piece has another problem

[95yj4]

So my jeeps actin funny. My thoughts are either torque converter or fuel pump (leanin more towards converter). So what happens is after driving an hour and a half on the freeway to get home everyday, I then drive another 20-30min on reg streets. Well this is the time that it starts gettin screwy, today especially. When I press the pedal softly it starts to accel but then acts like it hits a wall, then jumps again and gives again. Today though, I would hit the gas softly and it would be all over; rev slow, jump, almost die, all of those circumstances for the last 2 miles to get to my house, and pretty rapidly, too. I really dont think its the fuel pump cause I do 80 on the freeway for most of the stretch without a problem. In fact it drives really well on the freeway for what it is. So if anyone has any info it would be very appreciated.

[stan98tj]

could it be ur tranny? mine gets screwy in first gear...no problems on the highway but as soon as i get down to the street and go to a light, as i pull from a stop it revs hard and doesnt exactly shift if im light on the gas. if i press the gas down normaly or hard there is no slip whatsoever..sometimes it gets caught in between it seems if im light on the gas where it revs and revs for a second or two and then shifts....from second gear on its all good.  maybe ur tranny is slipping? thats what i think mine is doin it may be the case with urs as well.

[Mr_Random]

So my jeeps actin funny. My thoughts are either torque converter or fuel pump (leanin more towards converter). So what happens is after driving an hour and a half on the freeway to get home everyday, I then drive another 20-30min on reg streets. Well this is the time that it starts gettin screwy, today especially. When I press the pedal softly it starts to accel but then acts like it hits a wall, then jumps again and gives again. Today though, I would hit the gas softly and it would be all over; rev slow, jump, almost die, all of those circumstances for the last 2 miles to get to my house, and pretty rapidly, too. I really dont think its the fuel pump cause I do 80 on the freeway for most of the stretch without a problem. In fact it drives really well on the freeway for what it is. So if anyone has any info it would be very appreciated.

I would bet fuel pump, did the same thing to me, and mine is stick!

First time I drove probably 180 miles at full speed, then got slowed down for a border patrol stop and it died once I got around 25mph... it's that the pump is getting hot while driving for so long, but the high flow of the fuel keeps it cool enough to function, but when you slow down the flow greatly decreases and the heat catches up with it, causing it to cut out. This problem gets more severe with the less fuel you have in the tank...

Although you could blame the 'converter too... so you can swap in a 5 speed and make it less of a turd...

[jfrabat]

When my fuel pump went, what it felt like was a sputtering, like the engine wanted to die on me when under load.  The effect would start with heavy loads, but then it would start getting worse and worse.  Then the problem would completely go away when I let the Jeep cool off, and re-start after a while again (sometimes not for days, sometimes after 2 minutes).  And the hotter the day, the worse the problem got (dont know why).  I replaced the pump, injectors and fuel rail (injectors and fuel rail were due to the fact that my fuel rail had cracked and I found some gunk in there) and changed the fuel filter (I tried this before changing the fuel pump just to be sure it was not the culprit) and I have not had the problem since.

I guess it could be your fuel pump, but I dont know squat about torque converters, so I dont know if that could be the cause of the problem.

[95yj4]

thanks for the help. I really couldnt see how it would be the fuel pump but now it makes sense. alright well i'll have to do some looking around and testing. Thanks for now though.

[Mr_Random]

When my fuel pump went, what it felt like was a sputtering, like the engine wanted to die on me when under load.  The effect would start with heavy loads, but then it would start getting worse and worse.  Then the problem would completely go away when I let the Jeep cool off, and re-start after a while again (sometimes not for days, sometimes after 2 minutes).  And the hotter the day, the worse the problem got (dont know why).  I replaced the pump, injectors and fuel rail (injectors and fuel rail were due to the fact that my fuel rail had cracked and I found some gunk in there) and changed the fuel filter (I tried this before changing the fuel pump just to be sure it was not the culprit) and I have not had the problem since.

I guess it could be your fuel pump, but I dont know squat about torque converters, so I dont know if that could be the cause of the problem.

Ha, didn't read my post did you?

Oh, and another thing; I think all TJ's have a fourth wire to the 'pump to measure heat; If it overheats the ASD will activate and NOTHING will work. It's meant to prolong the life of the fuel pump, but I'm sure it can be annoying unless you know the codes or have a reader.

[95yj4]

Alright, so I gave in and took the jeep into a local repair shop. Didn't have the time to work on it and they're actually a really good shop. 3 days of messin with it and they cant find anything wrong except they said the fuel pressure was low, 30 instead of 38-42psi. But I just looked in my manual and its saying 31psi. Which one is it? Another question I have is that I was told by a few people that I have to replace the whole assembly, but then I hear from a few more people that say that I should only need the pump and strainer. What would you recommend? So now I HAVE to try and fix this thing over the weekend.
Oh one more question, I noticed on my voltage gauge that its been very, very slowly been going up over time. I think its up to 15volts maybe a little more. Could the pump be causing that, too?

[oldjeep]

1) Can't trust the voltage gauge in a YJ.  Hook up a multimeter when the jeep is running and see what it says.
2) In a 95YJ, you should be able to just replace the pump
3) Have you replaced the fuel filter?  IF not, start with that - they are cheaper than a new pump

[oldjeep]

And as for the fuel pressure, this is from the 94 FSM.

FUEL SYSTEM PRESSURE TEST
The fuel system is equipped with a vacuum assisted
fuel pressure regulator (Fig. . With engine at
idle speed, system fuel pressure should be approximately
214 kPa (31 psi) with the vacuum line connected
to the regulator. With the vacuum line
disconnected from the regulator, fuel pressure should
be approximately 269 kPa (39 psi). This is 55-69 kPa
(8-10 psi) higher.
(1) Remove the protective cap at the fuel rail (Fig.
7). Connect the 0-414 kPa (0-60 psi) fuel pressure
gauge (from Gauge Set 5069) to test port pressure fitting
on fuel rail (Fig. 9).
(2) Note pressure gauge reading. Fuel pressure
should be approximately 214 kPa (31 psi) at idle.
(3) Disconnect vacuum line (hose) at fuel pressure
regulator (Fig. . Note gauge reading. With vacuum
line disconnected, fuel pressure should rise to approximately
269 kPa (39 psi).
Fuel pressure should be approximately 55-69 kPa
(8-10 psi) higher with vacuum line removed from
regulator. If not, inspect pressure regulator vacuum
line for leaks, kinks or blockage. If vacuum line
checks OK and fuel pressure does not rise approximately
8-10 psi after disconnecting vacuum line, replace
fuel pressure regulator.
The fuel pressure regulator is not adjustable.
(4) If fuel pressure exceeds 45 psi, check fuel return
line/tube for kinks or obstructions.
If the previous tests checked good, fuel pump pressure
is correct. If pump pressure was low, proceed as
follows:
(5) Release fuel system pressure. Refer to the previous
Fuel Pressure Release Procedure in this group.
(6) Disconnect the 5/16 inch fuel return line quickconnect
fitting at fuel rail. For procedures, refer to
Fuel Tubes/Lines/Hoses and Clamps. Also refer to
Quick-Connect Fittings. These can be found in the
Fuel Delivery System section of this group.
Connect Fuel Line Pressure Test Adapter Tool
number 6539 (5/16 in.) between the disconnected fuel
return line and fuel rail (Fig. 10).

[95yj4]

Alright so its been a while since i was on here. Had the fuel filter replaced a couple months ago so thats not the problem. I went and bought a new pump and strainer. I attempted to drop the tankbut no go, too much rust and undercoat. Took it into the shop and had them do it. The problem actually became worse. So I said screw it and gave it to my brother and bought a new car. Since then the jeep wouldnt start and come to find out the battery had a dead cell. Supposedly a battery with a dead cell can mess with the MAP sensor so that could have been the problem. I really dont know if it was cause my brother never drives freeway. So now I no longer have the jeep but maybe I can get it back one day, or just get another one, who knows.

[Mr_Random]

That's a shame... sorry you had to get rid of it!

[95yjman]

That sucks bud