93 RRC stalling issue

[CajunRover]

I have a 1993 Range Rover County LWB with an odd issue. When I reach 1600 RPMs the engine stalls out and drops 250 RPMs before it kicks back on. If I stay under 1600 it starts and runs fine. Also this issue doesn't start for about a minute after ignition. Any ideas???

 

[RoverGuy7]

That could be a lot of different things, from a failed sensor, ignition module, your timing advance inside the distributor, clogged catalytic converters, and the list goes on...

Does this only happen while driving, or in neutral as well?
If only in gear, same thing for each gear, and same if power-braking?

 

[CajunRover]

It doesn't happen in neutral, but it happens in every gear and always at the exact same RPMs. I've never tried it power braking. She's on her last leg as it is hahah.

 

[RoverGuy7]

Then yeah, maybe hold off of turning your trans into a big box of neutrals...

With it able to rev fine in neutral, you're looking at something load dependent, not just speed dependent, which unfortunately doesn't help as much as the other way around would.
I would start with the basics, fuel pressure, and checking out the ignition system, both internal to the distributor, and the coil and condenser circuitry.

Did this happen all of a sudden, over time and get worse, or come into play when something else was fixed?

 

[CajunRover]

It pretty much just happened all of a sudden. At first it was just an intermittent issue and it would happen randomly for 5 minutes or so. Then one day I filled the tank and it started doing it all the time.

It's also dependent and proportional to the last time I drove it. I went on vacation and when I came back it ran fine for about 2 days then started again. If I wait a week it will run fine for a day or if I'm lucky a little more. This makes me think maybe there's debris in the tank that get's kicked up and clogs the fuel pump. But at the same time, it always being at the same exact RPMs makes me think a sensor issue.