• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Stalls at 4 Grand

moparmatt

moparmatt

NAXJA Forum User
Location
South Bend, Indiana
A few days ago I was on my way to work. I take the by-pass the speed limit is 65mph.

I was passing a semi and as soon as my motor hit 4,000rpms, it was like the motor or trans gave up.

But the motor does not shut off. I simply take my foot off of the throttle and press it again and it is back to normal. No check eng light or backfire nothing except a huge loss of power.

I cannot figure it out, is it the motor or trans that is doing this?

Now I know the simply solution is not to hit 4K rpms.

4.0L AW4 d35 stock drivetrain only performance mod is a cold air intake.

TIA
 
95 XJ

Like 1/2 to 3/4 full

Fuel filter don't know

Rev Limiter cannot be (don't think it has one, plus the red line is like at 6200 anyway)

It only happens at 4 K rpms and i have done it multi times trying to figure it out

FYI mph does not matter it happens at 35mph and at 60mph
 
Only In A Jeep XJ said:
Rev limiter
Click to expand...
Not at 4 grand though, it should go to a little over 5000rpm, im assuming it downshifting to second if you floored it which would give it a good jump up there. Maybe you had issues with fuel not getting to the engine or something. Do you have a problem during warmup or any other time?
 
Just read your last post, maybe its an early fuel cutoff because you're not gettin enough in there due to a clog or something, try some fuel system cleaner at auto zone. Do you get a check engine light at all? And you gotta take a grand off that redline guestimation, though that would be interesting.
 
6200 rpm is past the point where valves float in a stock 4.0, if you even try to take it that high, i'm sorry for your poor motor.

4800-5000 is about where it should redline, and taking it higher than 4500 on a regular basis isn't great for them.

Clean your fuel system, as BBeach stated, and change your fuel filter.

It's not a Honda, so don't rev it like it is.
 
BBeach said:
Just read your last post, maybe its an early fuel cutoff because you're not gettin enough in there due to a clog or something, try some fuel system cleaner at auto zone. Do you get a check engine light at all? And you gotta take a grand off that redline guestimation, though that would be interesting.
Click to expand...

I am going to change the fuel filter. (I pray it is not the pump) And see if that solves the problem.

But my only worry is that this stalling is consistent at exactally 4000 RPMs.

And when it does stall the motor does NOT shut off.
 
nekocopter said:
6200 rpm is past the point where valves float in a stock 4.0, if you even try to take it that high, i'm sorry for your poor motor.

4800-5000 is about where it should redline, and taking it higher than 4500 on a regular basis isn't great for them.

Clean your fuel system, as BBeach stated, and change your fuel filter.

It's not a Honda, so don't rev it like it is.
Click to expand...

Dude don't cut me down like that.

I was passing a few semis on the bypass and my exit was near. I take real good care of my Jeep and it takes care of me.

I don't mean to start any drama, Thanks for the tips.

So it looks like a trip to NAPA tommorow.

I know around here NAPA is announcing that if you bring in an old hat they will give you a new one.
 
moparmatt said:
I am going to change the fuel filter. (I pray it is not the pump) And see if that solves the problem.

But my only worry is that this stalling is consistent at exactally 4000 RPMs.

And when it does stall the motor does NOT shut off.
Click to expand...
Have you messed around with the ECU at all or have tried out a jet chip or some gimmick ebay chip? Or hypertech tuners can adjust rev limiter? Have you been past 4000rpm before within the past couple days?
 
BBeach said:
Have you messed around with the ECU at all or have tried out a jet chip or some gimmick ebay chip? Or hypertech tuners can adjust rev limiter? Have you been past 4000rpm before within the past couple days?
Click to expand...

Na I do not play with the ECU. No High Performance chips.

I really do not remember the last time I hit 4K before it stalled. I really do not push it. But the stalling just bugs the hell out of me.

Do you think a cold air intake (bad fuel mixture at 4K) could cause this?
 
I would check the fuel pressure. You may be able to fish the hose through the bulkhead connector and watch the fuel pressure while your driving. The second test would be the fuel volume test. Its in the fsm or search. Use caution with fuel tests, you don't want her to catch fire. Well ..................I don't think you want her to catch fire:)
 
It was the fuel filter.

Note: Never trust the previous owners records.:flamemad:

That old fuel filter poured out tons of black $H!7 on the input side.

Took it out of a test run and it runs like a new Jeep. No more stalling. :D

Funny how there was precisely enought $H!7 for it to stall at exactally 4,000 rpms. Well I guess thats what happens at W.O.T.
 
Glad you found the problem. Now make sure to run some Seafoam or Lucas gas treatment every so often to keep everything clean.
 
Just for those that find this in a search. I had the exact same symptoms, and replaced my ff.....all the black gunk came out all nasty and such. Still had the problems, and replaced the pump(not a bad job.....took a noob about three hours to do) and it was fixed.
 
dspilot said:
Just for those that find this in a search. I had the exact same symptoms, and replaced my ff.....all the black gunk came out all nasty and such. Still had the problems, and replaced the pump(not a bad job.....took a noob about three hours to do) and it was fixed.
Click to expand...

As a side note, make sure to replace the big o-ring that seals the pump and the tank when the pump is replaced. It is easy to replace when you are doing the change......not so fun when you find it leaks because you didn't do it!
 
You must log in or register to reply here.

Similar threads

O
2000 XJ Failed Colorado Emissions high CO
2
Replies
27
Views
2K
Ken M
K
M
NP 231 input shaft
Replies
3
Views
2K
RCP Phx
R
A
2000 xj aw4 on 34s 4.88 or 5.13
2 3
Replies
49
Views
5K
Andre2000
A
L
Manual to Auto transmission swap
Replies
9
Views
205
lvcanyoneer1
L
M
2000 cherokee chk eng light
Replies
11
Views
1K
XJI6191
X
Back
Top