QuestionJohn, your advise on previous questions has been great. I hope you can help me out.
I have a 1997 Disco II. The engine has been running a little sporadically, but seems to be getting worse. The engine would surge from time to time and lose power. Today, it kept doing it. We stopped the vehicle for 20 minutes, then it seemed fine for about the next 10 miles. Then it started again. The check engine light came on.
For the record, we just had it looked at because of this problem and the computer diagnosis showed nothing wrong.
Any thoughts?
AnswerHi Eddie,
glad I can help you out. This problem is a bit more complicated...it could be (worse case) the dreaded sticking exhaust valve problem that is common to series II Disco's.
It could also be just the TPS (throttle position sensor) or coilpack. Check the spark plugs and wires, replace if they are worn or old. Last summer, I replaced my wires with new ones from the dealers. Cost me $120. Only 4 months later I had the same problems you have described and after careful testing found that 2 of wires had shorted out. Rare but possible.
From now on, I buy only the best wires I can find. I'm testing out some new ones this week!
If you had your Disco on a testbook and nothing was found wrong, it could very well be a sensor problem. Intermittent sensor failures could sneak by the testbook diagnostics.
Just make sure all the 'usual suspects' are in top shape: wires, plugs, filters, serpentine belt, battery and alternator.
You may have to have your engine further diagnosed for the sticking exhaust valve problem. Fix: $2500 valve job. OUCH!
Best of luck,
JohnMc
