After 3 miles or so my 3.2 is misfiring badly before cutting out completely. After parking up and cooling down she will start and run again then repeat same. From cold she starts first time everytime and is sweet. Any suggestions? Thank you. J.

 

Is it giving any clues like smoke or sounds? Off the cuff, I think I would check fuel supply first, if the pump is heating up and cutting out consistently it may not give a clue. Also a quick and easy check might be under the distributor cap. I recently had my center button get stuck causing a no start. An aggravatingly simple fix. Good ;uck!

 

You can check fuel pump as stated by jerry, make sure you're correct pressure... 30-35 psi ignition on, 40-45 psi running at idle, etc....


Since you say it cuts out once warm, maybe check the crank sensor as well - common issue with XJ40's and X300's

 

Hi jjd,

The first thing I would suggest is that you check the Vehicle Condition Monitor for any stored Diagnostic Trouble Codes (DTCs). To do so, turn the key to position II (ON) but do not start the engine. Press and release the VCM button on the trip computer alongside the steering wheel. Now watch for a message in the small window below the speedometer where the odometer/mileage display usually appears. DTCs are displayed in the form of "FF" or "Fuel Fault" plus a two-digit number (there are some one-digit codes on the '87-'89 cars). Examples of how codes appear are FF89 or Fuel Fault 22.

Write down any DTC exactly as it appears and post it here and we'll try to help.

Problems like this are often the result of multiple contributing factors, so my first question for you is: how long has it been since the car had a good tuneup? Air filter, fuel filter, sparking plugs and leads, distributor cap and rotor, air intake plumbing and throttle body cleaned, throttle position sensor cleaned, crankshaft position sensor body and electrical connector cleaned, ignition coil and amplifier wiring inspected, fuel injector cleaner in a tank of petrol, drive belts re-tensioned or replaced, battery power and ground connections throughout the car cleaned, etc.?

Some other possible suspects would include a problem with the engine coolant temperature sensor (CTS) that if stuck on a cold setting causes the engine control module (ECM) to continue applying cold-start fuel enrichment even after the engine warms up; a problem with the oxygen sensor, which the ECM ignores for its initial warm-up period before going into closed-loop fueling. Also possible is a failed diaphragm in the fuel pressure regulator allowing unmetered fuel to be inhaled into the intake manifold, causing a rich air-fuel mixture. You can test for this by pulling the vacuum hose off of the regulator, cranking the engine, then checking for wet fuel at the vacuum hose fitting on the regulator which indicates failure of the diaphragm.

Cheers,

Don

 

Great responses as always folks. Thank you so much. I'm off work for a few days this week and I'll go thru these points. Hopefully I can report back good news. Once again thanks for the assistance.

 

VCM displays..pad fail. Do that is another days work plugs leads etc appear to be fine....now this car was laying up for a few years before I rescued her and was let run out of fuel on a number of occasions. I have filled with fuel and a hard driving seems to be lessening the issue. Where is the fuel filter as I feel a new filter could do wonders for her.

 

The fuel filter is located just ahead of the left rear wheel. It's a metal cylinder about 4"-5" long and about an 1-1/2" in diameter.

Larry

 

I had similar problem with my 94 Sovereign 4.0l and I was on the point of organising an exorcism after trying everything. The problem was that even though the Crank sensor was reading the correct resistance when cold it was knackered when hot and once replaced the problem was solved.
Good luck

 

Any update? I too am seeing this on a sporatic timeframe. I was thinking coil but those guys are expensive. My vanden plas has also been sitting for years upon my saving it.

 

. No problems at all since I replaced the sensor, engine runs smooth and has lost it's intermittent misfire. Unfortunately, as I am now retired and don't use her as much as I should plus the fact that my alternator has just seized, it is now time for her to be reborn as a fridge freezer and go to that great scrap yard in the sky. Good luck