Bump...Stop (running that is)

[mrbill3]

I have a good one. (searched but, no matches) Tonight I was pulling into a gas station to donate my paycheck and it has a fairly steep uphill driveway with a bump as you hit the uphill part. When I hit the bump my rig stalled out. It restarted right away and then ran fine. The only other problem it has is that it is hard to start after it has been running for a while and then sits for a few minutes. Like going to Home Depot and making purchase then coming back out to leave. It will crank over like usual but at the point that it would usually start, it sounds like it wants to start, but then goes back to cranking again. It will do this a couple of times and still not start. If I leave it sit for about 10 to 15 seconds it will start and be fine. I don't know if the two problems are related, but......

[Gabewatt]

what year is your jeep? what kinda engine and trany? help us help you

[mrbill3]

Originally Posted by Gabewatt

what year is your jeep? what kinda engine and trany? help us help you

Well I don't know what happend to my Signature, all the info was there. Any way here it is:

89XJ Laredo, 2 door, 4.0L, Automatic. Rusty's 3" Full-Spring Pack Lift, Steering Stabilizer, Bumpstops, and Seering Brace. ProComp 31X10.5X15 AT's on 8" Steelies. Dynomax Super-Turbo Cat Back.

[MagicRat]

My guess is that it may be fuel pressure related.

Maybe the fuel pump's electrical roll-over safety switch got knocked loose going over the bump, allowing only intermittent power to the pump.

Perhaps the fuel pressure regulator has failed, or the pump or the pump's one-way valve is stuck. Either way, the fuel line may be losing pressure when the vehicle is parked, causing hard starting, until the pump pressurises the line,

[jeepgirl82]

My 88 cherokee does that Too. whenever i hit a bump talking a left it stalls. Still no idea what it is, but it always starts right back up.

[Gabewatt]

sounds like a bad relay/conection/ground wire somewhere. start checking them all. at the age of our jeeps things start to all go at once.

[jeepgirl82]

someone suggested the crankshaft position sensor, the shealth on my cable looks frayed<or melted is more like it> and was hitting a piece of metal that was grounding it out. i moved it and my problem was kinda solved to my new more freaky problem that puzzles everyone!

[raeuspius]

Check the ground in the fuel tank where the pump is located. I would bet my paycheck this is your problem. Your fuel pump has to ground to work properly.

Relays typically aren't intermitant. Either they work or they don't work. You can bang on one and get it to contact but it wil not work again.

[mrbill3]

Well I checked all of the relays today and they are fine. I aslo checked the wiring and the bolts on the cps and everything was okay there too. I am going to order a new CPS tomorrow (My brother-in-law works for NAPA and is coming for turkey day. He's also bringing my new rear/front main seals, oil pump, oil pan gasket, valve cover gasket, and serp. and hoses) while I was at it I cleaned the gounds and battery terminals, but.......I still have the problem. I think raeuspias mybe on the right track. I will check the pump ground next.

[refrigerationdude]

Mine does that starting thing too, except I usually don't hold the starter on when its tryin to catch, I usually leave off, and it sounds like its only firing on a few cylinders then it dies. I crank again and it fires up fine and runs fine. I still haven't found the cause yet to my issue. Its a little diffrent int he time too, as mine has to sit between and hour and 3 hrs for it to act up, anything less or longer it dosen't do it. Thats what has me realy baffled the time periods involved.

If you find out what it is let us know.

Thanks.

[baum430]

Originally Posted by mrbill3

Well I checked all of the relays today and they are fine. I aslo checked the wiring and the bolts on the cps and everything was okay there too. I am going to order a new CPS tomorrow (My brother-in-law works for NAPA and is coming for turkey day. He's also bringing my new rear/front main seals, oil pump, oil pan gasket, valve cover gasket, and serp. and hoses) while I was at it I cleaned the gounds and battery terminals, but.......I still have the problem. I think raeuspias mybe on the right track. I will check the pump ground next.

if its not relay it could be at the pump in tank they have a pressure
relief valve sometimes it will stick open . i changed mine when it ran so fast you could here with the engine running. pump is woking all of the
time ,gas deposit buildup and old age a factor.