Hey guys,

I just recently replaced my fuel pump. It got my rig started again but it didn't solve any of the other issues my XJ has and I figure I might as well figure out what's going on. None of the issues render the car undrivable but they are somewhat pesky and I'm a bit worried they'll manifest themselves in a more severe manner later down the line.

Some of these may be really simple fixes, but I am mechanically stupid. But I'm learning!

#1 - Bucking and lurching
This only seems to happen in second gear. When I'm trying to accelerate the rig bucks and lurches a bit. It feels like I'm tapping on the brakes, but I'm certainly not. It's worse when going uphill, but once it shifts up, there are no problems.

#2 - Dropping out of gear when shifting
Sometimes when shifting from 2nd gear to 3rd gear, instead of switching gears, the rig just seems to drop out of gear, and seemingly into neutral. The only way I've found to get it back into gear is either to stop completely (which isn't always possible in city driving), or to let your foot off the gas entirely, let the RPMs drop to idling, and then mash the gas pedal, which forces it to rev up and "catch" and then it will get in gear.

3# - Stalling when going slow and/or over bumps
This is an issue I had hoped a new fuel pump would solve. It only happens after the car has had time to warm up. If I'm driving the engine on a cold start, it won't happen until 15-20 minutes later. It normally happens any time after I stop or slow down after driving it around a while: parking lots, red lights, back roads, etc. It also sometimes stall out if I hit a speed bump a little too roughly.

Any help or advice you guys have on the issue is greatly appreciated.

 

Click on the link in my signature and do the procedures outlined in posts 1,2, 3, and 5.

 

Thanks, I will. I'll update this thread with any new info.

 

We're counting on ya to do so.

 

Plugs clean and gapped at .035? Distributor cap and rotor are clean?

 

It's super icy outside so I am definitely in 4WD, but I get the same issues in 2WD. The tranny fluid is full and looks good. I haven't had a chance to check the CPS but I will as per cruiser54's post, if his previous suggestions don't make any progress.

I assume that means spark plugs? I wasn't kidding when I said I was mechanically stupid.

Seriously stupid question coming here, but where can I find the distributor cap and rotor?

 

Sounds like Renix vacuum troubles to me. Check all vacuum lines and make sure all are routed correctly. A broken or leaky line can make an 87 run terrible and kill your gas mileage.

 

My gas mileage is pretty damn awful... I will look into this as well. Poor Jeep needs a lot of work.

 

Yes, spark plugs. They are in a row on the right side. (that's the passenger side). Each one has a large wire going to the distributor cap. The cap comes off with two screws and the rotor is below, pulls right off. The spark comes from the coil to the center of the cap where the rotor "distributes" it, to the different plugs.

Basic tune-up is to change all that stuff. You probably want an uncle or a neighbor or someone to show you through the first time, at least.

 

Awesome. I have cleaned and changed spark plugs out before and I have a terminal cleaner somewhere.

 

OK, do check that whatever goes in is gapped to .035. Bucking, lurching and stalling....besides Cruisers list I'd be sure it had a little love there. (cap, plugs and wires)

In 4WD, if it has traction it might "bind", drag...like someone pressed the brake, is why I mentioned that. Maybe not so much going straight with matching tires, but definitely turning it would bind and feel like the brake got pushed.