does it from cold, and gets no better even when warm, really frustrating as it was due for a mudbath on sunday

 

Man, that sucks. It is really depressing when you cannot bathe your truck in the proper solution.
Clogged fuel filter maybe?

 

Got your thoughts on putting in the old MAF. Just did that and it seems to be working better. No hesitation when throttling up. At least in the shop. Will take it out tomorrow for a run. And the MAF I bought was on eBay of a guy called the MAF guy. Claims it was new. But not sure now, maybe just cleaned and painted a used one. The price sold it to me. But bargains sometimes will bite you. Thanks again for your input. Your Rover Heroes.

 

Yeah thats the problem with buying off of e-bay, you dont always know what you are getting.

 

I'm still working on the same issue as well. 98 D1 with 106K. New plugs, magnecor wires, new O2 sensors, seafoamed intake, carb cleaned the throttle, new fuel filter, and have run several cans of seafoam through the tank. Getting the random misfire codes and a general misfire code. If I push the throttle to the floor near the point where it would downshift, it smooths out. Partial throttle it stumbles all over the place... also if I manually shift from a stop I can feel a "kick" around 3250RPM almost as if 2 cyls just turn on. Haven't touched the MAF though, as I have no codes for it. Suppose at this point it wouldn't matter though!

 

I have been racking my little brain on this all day and this last reply really helpsshed some light.
Have you guys looked at the injectors them selves?
jdhuegel1, you say that it feels like two cylinders just "kick in", maybe two injectors are not working until a certain point?
Can you unplug one injector at a time and see if there is a difference or not?
There was a guy who had a post that his truck was only running on 4 cylinders, it ran and went down the road but not very well. Turns out that the controller for the injectors was bad or something like that.

 

Thanks for the reply Spike! I've been thinking injectors also. Maybe sticking or something... or an ignition problem of some sort but that seems somewhat less likely. Is it safe to unplug an injector and drive the vehicle? It idles and revvs in neutral like a new truck, it's just under load it acts up. If safe, I'll do it and see what we can make of the results. As for the kick in thing, it's really strange. It SEEMS to be running decent then it kicks in and feels twice as powerful.

There's another little issue too that I THINK is the VSS. While driving, the truck will suddenly feel like it cuts out the injectors. I pretty much can't accelerate BUT, if I let off the throttle completely and then push again all is well. There is no strange activity on the speedo though, which is confusing.

Justin

 

I forgot about the VSS, I would replace that first and see what happens. It is a simple job and they have detailed instructions on www.discoweb.org under the tech section.
And yes, it is safe to unplug a injector and drive that way.
Cadillacs have a "limp" mode which is when the ECU kills some injectors to reduce power, you can drive all day like that but you cannot go very fast.

 

Ok cool, thanks Spike. Let me get my hands on that sensor and see what happens!

Justin

 

PLEASE keep us posted.