1995 disco 1 slowly losing power.any ideas?

[motorover]

I have 115k on my disco 1 5 speed new plugs, wires ,cap ,rotor,fuel filter,cats have been removed long time ago but i have noticed that it struggles up the long grades now and i even have to downshift when i didnt before.It also has a very slight miss or hesitation,not really a stumble that also wasnt there before.I found fuel regulator vacuum line rotted and replaced but no change.How much pressure should i see at idle on the rail in psi.I got confused looking in rave at kgf/cm2 readings.Any ideas where to look next.This has been a great truck otherwise.No codes or lights on either.Could the coil be fading?..Thanks.

 

[p m]

35psi is a good number.

 

[motorover]

Checked fuel pressure.Got 35 psi on rail at idle,mabey 5 more when i rev it.removed mass air flow and cleaned.Test drove and no change.Still has mild surge and low power.

 

[RoverbyProxy]

Could have problem with the injectors, quality of fuel, what type of sp plugs? properly gaped? Did problem come up with change in weather temp?

 

[motorover]

Tested injectors for leakage,has new champion plugs,properly gapped and always use premium fuel.Weather change has no afffect on it.This truck maintains a solid temp. and coolant level better than any Rover I have owned. Has anyone used the spark testors with the adjustable gap to check ignition system integrity?

 

[RoverbyProxy]

Throwing some more ideas out there.. How about the throttle plate, clean and clear of carbon? I assume air filter is ok. With the fuel pressure reg not getting vacuum possible that the valves are carboned up. Compression test? Cylinder leak down test? Possible just normal engine wear.

 

[wheelen disco]

The cam and lifters could be very worn. Are there any ticking noises

 

[DarylJ]

The cam and lifters could be very worn.

Going down that line of thought, I'm surprised no one has mentioned the timing chain. 115 doesn't sound like much, but if it hasn't been serviced well (especially oil) the chain could be one disgusting sloppy mess.

 

[motorover]

No ticking noises,cam wear could be a factor but if timing chain was sloppy I would expect the timing check would be moving around and this one is solid when checking timing with the light.Thanks for all your input,still checkin and rechecking.

 

[DarylJ]

if timing chain was sloppy I would expect the timing check would be moving around and this one is solid when checking timing with the light.

It's not fair when you're holding back information.

 

[adumee]

Fuel injector cleaner fixed this for me a long time ago, now with new fuel pump never have the problem

 

[motorover]

I just wanted to respond and let anyone interested know what I found on this surging and losing power issue.I finally pulled out the distributor ,disassembled it and low and behold the top part of the centrifugal advance was frozen to the inner shaft. I never thought it would make that much difference in power and cause the surging. I was able to remove everthing,clean and re-lubricate it all.So if you have a truck with a distributor,make sure you can turn the rotor clockwise just a little and it must spring back on its own.If not,you could be losing some power.This thing flies now.

 

[DiscoSux]

I just wanted to respond and let anyone interested know what I found on this surging and losing power issue.

Thanks for the update. I'm on it with my '95! atriot:

 

[ptschram]

Vac advance can good? If the plate wasn't moving, the diaphragm could well be toasted.

 

[motorover]

It was leaking as well. Already bought one from you and put it on.