So this morning I started my 2001 Disco 2 SE7, everything is fine and after about two mins of idling in my driveway (waiting for Wait Wait Don't Tell Me to start) I felt a little "blurp" I figured it was just a small hiccup and I am driving down my road to the main rd and as I'm idling at the light, its not necessarily missing, its just dropping a little bit in revs. I figured it just needed a little bit of gas so I drive straight to the gas station and fill it up. I drove it around a little bit, when I'm driving around the truck runs great! But when I'm at a light its sputters a bit and acts like its going to shut off. No check engine light, I recently replaced the plugs and purge valve last week, but I drove about 250 I miles yesterday, not one problem. This morning sputters at idle and when I stop. I drove to my future parents house and parked for a few mins, shut the truck off and when I got back in to leave, I started, it sputtered, and shut off. I tried cranking it back over but no start. it cranks and cranks, sounds like its juuuuuust about to start, but doesn't. I pulled the fuel pump assembly out and I'm trying to figure out which is bad, the CAS or the Fuel pump? When cranking, it sounds like its just about to start.

 

That is your fuel pump. The crank sensor goes out when it gets hot, like when you're on the freeway. If it only sputters at the light, then it is a fuel pump (or possibly the relay). At least that's what it was for me (relay).

 

iwould check the fuel pressure

 

I was stranded at my future inlaws, so I didnt have many tools. I did have my test light thought. When I I tested the plug-in to the fuel pump, no power out of any of the wires except the big white one when I was cranking it. Im thinking if it was the relay, I'd get no power whatsoever right? Or do I have it backwards, since there's no power to the smaller two wires, its the relay.

 

Oh man, I was having this exact same issue two weeks ago - check my previous posts.

In short, I replaced the battery and CPS. It now works fine.

If the CPS is faulty or works "intermittently" then this causes lack of fuel pressure which could be the really rough idling, stuttering and no-starts. (Correct me if I'm wrong however, that's just what I was told.) I got stranded too. The thing wouldn't start up on me.

CPS available at Autozone for $60.

 

My battery is maybe two months old. When you cranked your disco, did it almost start? When I crank it, it sounds just like a bad fuel pump. When I take off, it chuggs like its missing a cylinder until I got past 2k rpm but it drives pretty smooth at higher speeds.. Did your tach move at all? If I can save the unnecessary trip two hours away I will. Theres a Autozone near my house within walking distance.

 

Mine cranked, but wouldn't start. It made a "DUSH-duh-DUSH-duh" kind of noise. Like something was preventing the spark from igniting. I dunno.

I came on here to ask advice, everyone said it's either the CPS or Fuel Pump. I took a chance. I guessed CPS. My guess was right. Problem was solved.

The CPS goes kinda bad after a while any way. So if you replace it, and it turns out not to be a CPS issue, then you have still done a good thing by replacing it, as it's only a matter of time before that part craps out on you anyway. When the CPS goes bad, it'll leave you stranded.

I would try and do that first. If you're still having issues, then you'll know what it must be. Call ahead to Autozone. You are looking for part number: sU5570

See link: Crankshaft Position Sensor at AutoZone.com - Best Crankshaft Position Sensor Products for Cars, Trucks & SUVS

 

I really appreciate it, I'll get both parts today, and sped some time wth the FIL working on it. This whole thing started by going over to his place to look at buying his 42 cj2a. I think Nigel got a little jealous.

 

you can check the ckps with an obdII scanner, check the rpm while cranking if no rpm the ckps is no good

 

No problem, good luck and let us know the outcome.