I have a '99 disco II with a major problem
Start up is fine, but engine wants to die right away. It will barely keep running and then after a few minutes rpm's steady out at around 800.
When trying to drive I can barely get it up over 15 or 20 mph and it hesitates badly, sputtering.
On Saturday - Have checked spark plugs - great condition, gap set correctly. Battery/alternator both good. Spark plug wires good. Plenum gasket replaced about 6 months ago. Tested vaccuum - about 11 @ startup, then immediately drops to 6, slowly working itself up to about 14 after a 5-minute period @ idle. At approx. 3,000 RPM (Holding throttle steady) it reads 16 & then drops to 9 - 10 about every 10 seconds. Has about 120,000 miles on engine. The problem of not going over 15 mph happened as of last night, after these tests. But, it was hesitating badly the last few days prior to testing, and have had an ongoing worsening problem at startup.
fuel pressure is ok
no problem with cat conv's

Previously read codes before full failure were
p0133 sensor circuit slow response bank 1 sensor 1
p0134 sens circ no activity detected bank 1 sensor 1
p0171 system too lean bank 1
p0174 system too lean bank 2
p0300 random multi cylinder misfire detected
p0301 cyl 1 misfire
p0303 cyl 3 misfire
p0305 cyl 5 misfire
p0306 cyl 6 misfire
p0307 cyl 7 misfire
p0308 cyl 8 misfire

I hope that this helps with diagnosis
Thank you

 

Sounds like you have a whole bag full of problems.
First , have you cleaned out your idle control, few good shots of carb spary may help regain a proper start up and idle.
How old ar your plug wires and what make?
I realize you don't have codes for O2's but your's are warn out at your mileage.
Get back to me.
Mike

 

It sounds like one thing is effecting the rest. I doubt its from multiple problems. DiscoMikes on the right track. I would also check your fuel pressure - replaced the fuel filter at all?

 

Thanks for the tips. I'll give it a shot
My father-in-law thought maybe an intake manifold gasket for the compression loss so it's torn apart now. Waiting for gasket to get here. Will let you know when it's back together and I've tried your suggestion.
Thanks
Pat

 

Pat, while you have the intake of why not change your plug wires, if they are still the originails, it will sure run better. Go to Rover Connection and read up on the Magnacor plug wires.
Mike

 

all back together now. With similar hesitation problem still. Had codes read
p1300 manufacurer contrl. Ignition system or misfire
p0305 cylinder 5 misfire detected
p0307 cylinder 7 misfire detected
p0733 gear 3 ratio incorrect
p0734 gear 4 ratio incorrect
p0300 random/multiple cylinder misfire detected
p0308 misfire detected

Any thoughts?

 

Pat, get the Magnacor plug wires like I suggested. The intake manifold will not cause misfires across nearly all your pistons, plug wires will.
Mike

 

Thanks Mike
That was going to be my next step.
I wanted to get it back together. I'll let you know what happens.
What do you think are the best spark plugs to use?
Are there any to avoid?
Thanks
Pat

 

This is not a wire/plug issue.

 

98roverguy
What would be your next step to try?
Any help would be greatly appreciated
Thank you
Pat