98 Disco 1 - 146,000 miles
Disco runs great, but about 5 minutes into a drive, she will lose power and won't rev over 1000 RPM and slow to a crawl, as I try to rev it up, it spits and pops. I pull over and wait about 15 minutes and she's ready to go again, normally there is no more issues until the next time I drive it. It idles fine and never dies while it's acting up. I can shut it off and it restarts fine, but won't rev up until its ready.
Initially, there was no check engine light, but a week later it came on. Had codes read and it showed camshaft sensor, I replaced cam sensor and shut off light. Still had same problem. Several days later the light came back on. This time crank sensor and coil pack showed up on scan. I replaced coil packs, still acting up.
Here is a list of things I've replaced trying to fix it:
Fuel filter
Camshaft sensor
Coil packs
Throttle Position Sensor
and unplugged VSS to test

Anybody have ideas of what else I should look for?
Thank you

 

Sounds like a very unique situation. Sometimes the codes don't really lead to the real problem. If the vehicle runs good after each episode it might be a sticky valve in the transmission, which could get worse in time. A good transmission shop could clean it out. But this is just a guess based on the loss of power on cold start. - Good luck

 

Thank you LR
I failed to mention it does this at a stop too. It will idle fine in park and neutral, but won't rev up sitting still or driving.

 

No problem. Have you checked the fuel pressure? It should be just below 40 psi. How old is your fuel pump?

 

The fuel pressure is about 38 psi when its running good. I haven't been able to check it as its acting up though. I don't know how long the fuel pump has been in it. I haven't changed it since I've had the truck.

 

Update: since I've been at such a loss as what to do next, I replaced the crank sensor too.
When I removed the old one, the nipple was bent. I replaced it with a crank sensor from a running donor car, but it wouldn't start at all. I replaced the old sensor and now she will start, but runs erratically and dies periodically. Though, it does restart every time. Does anybody have any suggestions as to what is going on with my junker?

 

well 2 things come to mind....as they have happened to me( and others ) lol
1. un hook the battery an remove the ecu >>>>they sometimes get wet inside and that can cause a lot of bad to happen...you can take the covers off the ecu, clean / dry it and reseal it back up....the rnderwell rusts through and then the rust attacks the unprotected ecu...worth a look and..

2. a few of us with the "advanced evap " system have had the fuel tank pressure sensor fail and cause the tps / iacv/ ecu to go haywire....they all run on the same circuit for power...one way to check....roll up the carpet in back ...remove the pump access plate and un plug the sensor connector at the fuel pump hsg.....when my truck was acting up...it immeadiately ran better upon unplugging the sensor at the tank....