No start issue 1993 xj sport

New to forums, I've been searching and can't find anything definitive,
First off it's a 93 sport 4.0 5 speed. It has new crank sensor, new coil, new fuel pump, new cap rotor plugs and wires, ecm has been swapped with a known working unit. New o2 sensor , also upgraded the injectors. It cranks but won't start, it tries but won't catch. 3 times it has fired runs great for 1 minute then sputters out and dies. Tonight i decided to pour some fuel down the tb and it just cranked. It finally fired I revved it to try to clear the cylinders. It started missing and dropped down to 500 rpm and died.
Any one please help. Thank you

I don't know if the 93 has this, on the drivers side fender there might be a ceramic thing with two wires going to it. Those control the power going to the fuel pump. If you have this you can test it by connecting the two wires by a fuse.

When the XJ starts it bypasses this soon after its running it goes back to this meter and can cause stalling.
Also maybe swap the relays around to test.

Other causes to double check are cam sensor in distributor and make sure the battery is at full strength. Anything less than 12 Volts can cause issues.

But since you can get it to run on its own it sounds like fuel supply IMO.

The ballast is also new, relays have been switch around and fuel pump relay has been bypassed

Did it start this with new injectors?
How is the fuel pressure regulator?

If you can crank it and it runs for a min it seems like something is killing power to the pump, but if you bypassed it nothing should cut it.

You might test you are getting a spark when it fails like this. I may be concentrating on fuel when its something else.

It has great spark but ill check it again, I just bought it from a friend it ran great then quit and sat for 4 months, I'm determined to get it going. I just did the injectors but it didn't change a thing

Fuel filter? Anf put a mech fuel pressure gauge on it, compare your numbers to factory spec.

It stopped running before the injectors were changed?

Since you pour gas to the intake and it ran it seems like fuel. You've got a new pump and injector assuming those are good, then the next step would be to check the pressure at the rail as go1lum said. You might even work backwards from if the pressure at the rail is not to spec.

I have a old XJ with the 2.8 v6 that broke a drive shaft in the middle of nowhere, later had power trouble with it getting enough fuel because the drive shaft bent in fuel lines as it decided to part ways with the rest of the vehicle.

If the pressure is off then Id work from the tank forward. See if the pump is actually working right from close to the tank, it could be as simple as fuel filter. If the tank had crud or rust it'd be enough to clog it. Then I'd look for damaged lines. But I'd think the simple steps like pressure test and fuel filter would serve you better.
Also Check the grounds. Our disintegrated after all these years, never gave us a starting problem.

I can't remember what the fuel pressure regulator does if the vacuum line is disconnected or if it fails.

A search brought up bad gas cap causing no start issues. He thought he had a return line or venting issues. Ended up being the gas cap

I got the jeep not running

Mdewees93sport said:

I got the jeep not running

Click to expand...

Oy, that's always a slightly bigger headache than having it die in your hands.

That's my dilemma lol, I'll figure it eventually but would prefer sooner rather than later

the good news is you know it can run. I'd love to get my hands a 5 speed 4.0 jeep so I'd jump at the risk too.

of your things to check there is a sensor in the distributor, called pick up sender or Cam position, one of the two things people call CPS. Honestly I don't know what it does when it starts failing.

Since you poured gas in and it ran I'm thinking fuel supply. I'd check this before hunting down odd senders. Down side is if all else fails you might have to go to back basics with compression test and timing checks

Got it running it was out of time on he dist

Nice! Now you got yourself an XJ!

Guess it ran rough the last time because the timing was off.

It was weird when it would fire it ran great but it would die shortly and act like it ran out of fuel, I overlooked timing just for the fact it didn't back fire, pop through the intake or struggle cranking, finally got flustered enough with sensors and wiring, after testing the tps I check the timing and I was retarded a tooth, but ya I'm stoked, thanks for the help man

Drove it to work today w/ no issues $500 xj lives