• 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.

Stalling 4.0

OverlandZJ

OverlandZJ

NAXJA Member # 101
Location
Bristol,PA
My son's 94 YJ has a stalling issue. Picked it up in SC, ran it home and it ran fine. It sat for about 7-8 weeks while i swapped axles,susp,SYE etc.

Now it stalls when coming to a stop, if you tap the throttle it doesnt. I cant seem to find a vacuum leak.

TPS? Is 94 a non adjustable TPS?
 
GermanXJ said:
Could be because the gas has sat for to long, after the next fill up it should go away use 87 Octain.
Click to expand...


Should have mentioned it's had a few tanks run through it.

I did install a cable actuator (posi-lok)on the front axle, but plugged the switch on transfer. Now that i think about it...it's probably drawing vacuum elsewhere in the vac harness? I'm unfamiliar with the CAD axles..never owned one.
 
Are you sure the t/c is unlocking? you never said if it was manual or auto?
 
Also does it idle fine in nuatral/park?
 
can't help ya, bro, I am an auto guy, maybe tps just a guess
 
OK, i think i just figured this out. Keep in mind i'm unfamiliar with a disconnect axle.

With a disco axle it's drawing vacuum through the vacuum harness (in 2WD) to keep the fork/front axle disengaged?

Just called my son and asked if it was stalling when he was driving around town in 4WD the other night in the storm. It did not stall..

So, the front axle harness unplugged is my vacuum leak in 2WD allowing it to stall?

I'll remove the harness entirely tomorrow and plug anything i have to.
 
That is exactly what my daughter's 4.0 XJ did when the CPS was going out. Intermittent stalls at idle, sometimes she could catch it and keep it going by gassing it. It usually quit while waiting in traffic at a light or turn- not a good thing. Try a search for CPS and crankshaft position sensor - lots of information available. Incidentally, a vacuum leak usually results in high dle (more air getting to the engine), and not stalling.
 
It's fixed..

When we were building this i took the NP231 from his 87 YJ, swapped in a 23 spline input gear and converted to electrical speedo. We were waiting for a new speedo gear for the gearing/tire combo, just swapped it in. Problem fixed.

Computer was not getting a signal from the speedo and was allowing it to stall.
 
You must log in or register to reply here.

Similar threads

F
Stumped on this one!
2
Replies
29
Views
4K
Bent
Bent
G
Low vacuum
Replies
6
Views
2K
GravyDavey
G
A
Intermittent stalling
Replies
4
Views
943
Tim_MN
Tim_MN
cherokeefan_1
2000 4.0 build questions
Replies
5
Views
2K
75SV1
7
T
Backfiring issue
Replies
3
Views
717
8Mud
8Mud
Back
Top