98 Disco- Very Rough Running - A tale of misery

[Pedro_malo]

Well folks, about ready to call the "click and Clack" guys on this one.


Have a 98 Disco 1 with 75k miles. Normally runs great. A few months back after sitting for a week in an airport garage, it started sputtering, chugging and running like the Catalytic Convertor was completely jacked or the timing was way off.

Had it towed to a shop ( a seasoned rover mechanic) found to have codes for a bad camshaft and crankshaft sensors - both were replaced.

Problem disappeared, for a while.....

Back in shop again. No code errors, the poor running problem doesn't always happen - only sometimes (usually when my need for the truck is pressing)

My mechanic replaced the timing chain, and tested known good ECM, Air Flow Meter and Catalytic Convertor. Yet the problem remains, it seems to get worse (poor running, chugging, missing, it sounds and feels exhaust related) when placing load on engine or fast starts. Some days it runs just fine, on other days it is undriveable and can not accelerate over 25mph and sounds bloody aweful.

Any ideas? We've tested or replaced the following items:

ECM, Convertor, Air Flow Meter, Timing Chain, Crank Shaft Sensor, Camshaft Sensor.

Some of the earlier posts are close to my problem.
Thanks - Peter

[Adam in NYC USA]

A few points to ponder:

The car was sitting in a lot for a period of time. In many parking lots and garages, there are plenty of opportunities for small animals to climb up into the engine compartment. they like to chew on wiring and leave interesting things behind.

Grab a trouble light and do a inspection of the electrical systems and seat and reseat any and all electrical connectors. check the wiring for the oxygen sensors, the MAF, and look for anything chewed on.

Hard starting on a hot engine? Check the fuel line temp sensor. ( I forget the actual name) . Swap it out and see if that improves the situation.

Was the tank full at the time? is there water or sludge in the fuel line?

[Pedro_malo]

Thanks for the response. So yesterday the bloody Disco ran wonderfully, with the new timing chain it seems like a new truck. It rained a little last night. Trying to start this AM, car was pretty wet (don't know if this matters) and it started horribly. Lots of chugging, and what sounds like missing it just about cut off and stalled out while I was applying gas in park.


I checked most of the electrical components connections and just cleaned the MAF. Any ideas? Starting to think that perhaps water is getting into the fuel system somehow.

Thanks.

Peter

[Phototone]

Spark Plug wires can cause the symptoms you describe, and it would be worse in damp weather.

[Rovin4life]

did the idiot actually test the fuel pressure and due a fuel pressure leakdown test.

see quite a few 98s have fuel problems.

[lowwill]

New mechanic maybe?

[Pedro_malo]

Thanks guys- found to have a spotty Fuel Reg line..replaced ..but problem still occurs.... Ordering new PCV kit from British Atlantic and looking to replace fuel regulator relay - if I can find it on a 1998 Disco 1. LOL instructions on RAVE don't match. Nothing blue under kick plate.


Ideas?- This is bigger than me and my mechanic. Still spotty running, then sometimes .....awesome. Installed brand new plugs and wires, re-did several grounds throughout. Need to replace fuel filter - need instructions to de-pressurize fuel system. RAVE is appears to be wrong for the 98 on de-pressure.


Might SEAFoam - but frightened - given other problems.


Any help appreciated. Thanks. Peter