• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • 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.

Engine dies when trying to park uphill?

LockeXJ

NAXJA Forum User
Location
USA
In my attempts to get my 1994 XJ Sport running right, I've run into another isssue. If I'm driving up a hill, it can make it alright. However, if I try to completely halt the car on the hill, the engine will die, and I can't get it to start back up without rolling it to flat ground. It will try to crank but it's almost like it's not getting any fuel because it will not start or will immediately die again. I suspect something is going on in the fuel delivery, but wanted to hear if anyone else has had such an issue.

P.S. Could this be related at all to the TPS issues I've been chasing?
 
In-tank fuel pumps have check-valves to keep the fuel from flowing back into the fuel tank. When the fuel flows back into the tank, the fuel line goes dry. My in-tank fuel check-valve was leaking fuel back to the fuel tank too quickly. This caused my 88XJ to have hard starting issues. The fix is very simple. I bought an inexpensive all aluminium check valve, used for fuel systems, and installed it in the fuel line in front of the fuel filter located in the rear by the fuel tank. Problem solved.

Best regards,

CJR
 
Thanks, I’ll be sure to check that. While thinking about this last night I thought of another time that I was actually on completely flat ground but accidentally slammed the brakes and it killed the engine. The slamming on breaks felt pretty similar to the halt that happens when I stop it on a hill. So could this be some sort of issue with the brake booster vaccuum? Anyone know if that is related to fuel delivery?


Sent from my iPhone using Tapatalk
 
Don't suppose possible causes until you have some data. What if a loose wire only gets pulled the right way to stall the engine when the trans is in reverse ?

Test the fuel pressure and the check valve under similar conditions as the stalling episodes.
 
Right, I’ll try to get some diagnostics done. Also I should mention that it’s a 5 speed so hopefully it’s not any wires by the trans. But I’ll be tearing apart the loom this weekend to fix my TPS connection so I’ll check all the others, too.


Sent from my iPhone using Tapatalk
 
Said this in another thread but my dad drove over a tree with my 99 some years back evading a reckless driver. No damage but it damaged the wiring harness going to the fuel pump. We drove it 3 hours home but only ran if we kept a foot lightly on the gas when decelerating or stopped. May want to check the wiring harness since that's an easy visual thing

Sent from my SM-G950U using Tapatalk
 
Thanks, I’ll be sure to check that. While thinking about this last night I thought of another time that I was actually on completely flat ground but accidentally slammed the brakes and it killed the engine. The slamming on breaks felt pretty similar to the halt that happens when I stop it on a hill. So could this be some sort of issue with the brake booster vaccuum? Anyone know if that is related to fuel delivery?


Sent from my iPhone using Tapatalk


Reminds me of the old "engine dies when turning a corner" problem, which if memory serves ended up being worn mounts allowing engine to shift and put tension on something in the harness. Maybe do a visual on the engine/transmission mounts and under-hood fuse block, look for loose wire loom supports or connections, maybe wiggle some wires while it's sitting idling (if you go underneath to do the fuel pump harness, have someone standing on the brake pedal, of course), see if you can make this stall happen...
 
Thanks for the suggestions guys, I’ll try to replicate the issue and definitely will look through the wiring. I won’t have time until this weekend to do so, but once I do I’ll be sure to update the thread.


Sent from my iPhone using Tapatalk
 
I actually (somewhat) recreated the issues tonight. I would drive the car slowly, then slam on brakes. In the beginning, it didn't stall, but the more I did it the more frequently it would actually kill the engine. I also would let the car roll backwards and then slam the brakes. This killed it pretty consistently, and also brought on the CEL with my usual TPS code flashing. At first it showed no symptoms other than dying, but eventually the car was idling rough and sporradically. Once or twice the car didn't start back up after it stalling and I had to press the gas while cranking it to get it to start, but for the most part I could immediately crank it again-- which makes me think that there is still a problem with fuel delivery. So right now I think this is two seperate issues: one where it stalls after hard break (possibly an electrical issue with wires shorting out, maybe even related to my TPS issue), and one where it can't deliver fuel on an incline. As mentioned earlier I'll start to look into electrical stuff this weekend, and while I'm at it I'll replace the fuel filter and install an external check valve to see if that clears anything up.
 
Once again thanks to everyone for their suggestions. This weekend I managed to tear into my wiring harness at the TPS to look for issues. Where the harness went under the fuel rail cover I noticed a nick on one of the wires coming from the crankshaft position sensor, so I covered it in electrical tape. I'm not sure if that is actually what fixed my issue, but I have taken it for a test drive and no longer have any symptoms from the throttle position sensor (no misfires or sputters when hitting bumps). I also stopped it on a hill and it stayed alive perfectly fine. Just to test I killed the engine, and wouldn't you know it came right back to life. The car even sounded much better and handled well. So as of now all the issues are fixed! I'll update if anything else surfaces but for now I'm very happy with the vehicle.
 
Back
Top