Need help, 260E not running on all cylinders

[heyJ]

I have been mistreating my e class for a few weeks by taking it on very small journeys. Over the past week, it began to chug away when idle, to the point where my head literally bobs up and down when I am sitting in traffic. When the car warms up, it seems to get better, so if I flaw it I get at least above 40mph!

Can anybody help me with this one? It has newish leads, could it be the distributor? It just doesn't seem to be running like the old gal she was. Your help is very much appreciated.

 

[brandwooddixon]

It could be a MAF problem maybe? The test seems to be unplugging it whilst the engine is misbehaving. If matters improve then it's faulty.

Alternatively, have you checked the spark plugs for fouling? If your engine is burning a little oil then running cold a lot will make them prone to coking up.

 

[jibcl500]

If you unplug the MAF with the engine running it should stall the engine if the MAF is faulty.

Get you head gasket checked.

jib

 

[Richard Moakes]

If the car is a 260E, then I suspect it is late eighties or early nineties, no MAF, probably KE Jetronic?

Rotor arm, Distributor cap, spark plugs would be my first port of call, if no joy there then I would want to test the coil and then move onto the fuel systems.

Good Luck.

 

[kth286]

Yes - no maf.

Just take it on a good 30 mile run on uncongested motorway. The plugs are fouled presently.

Then see how it performs.

 

[Ian B Walker]

Check the compression. I bet number 2 cylinder is low. Mine was. It always seems to be that cylinder on 201's and 124's for some reason.

 

[brandwooddixon]

If you unplug the MAF with the engine running it should stall the engine if the MAF is faulty.
jib

That's what I originally thought and yet posts by Black55 and Television state otherwise. As my MAF is working I can't realy test it.

 

[stever]

When this happened on my car it turned out to be a faulty HT lead - it went away when the engine was properly warmed up, as this would drive out moisture from the leads that had been causing a short circuit.

Easiest way to test is to run the engine at night - you'll soon see any stray sparks from the leads, dizzy cap etc.