Hello jaguar forum members!

I have not been very active on here lately and before I asked for input I wanted to say I hope everyone is doing well. .
My question is my 1994 xj40 4.0 randomly stalls. It has only done it twice but it's pretty scary! I was sitting at a red light for about 2-4 minutes (car is running with AC on low). The turns green, I push the gas pedal and the jag VERY quietly died. Luckily I turn the key an it starts up right away... And takes off like a rocket!! I had my mechanic replace the alternator and put new spark plugs in a couple weeks before, but the first time it died was before I got the new alternator. There's no check engine light and the VCM gives me no codes... Also no strange sounds coming from under the hood. Any ideas guys?

 

Mike,

just a thought and I may be thinking in the wrong direction but when did you last service your transmission? It could be your torque converter causing the stall? or on a different track, a problem with your fuel system. ie a blocked filter?

 

Replace your fuel filter and grab a can of CRC maf cleaner and clean your maf.

 

Thanks for your input!

I should of added the fuel filter was the first thing I replaced after the engine first died back in the spring. So maybe it could be something with the tranny.

 

Hi there!

I have nearly the same problem with the stalling on my 94 Daimler XJ6/XJ40 4.0.
In my case however the stalling happens when I don't push the gas pedal (<- this is a maybe) and drive over a "bumpy" road and also in my case the Check Engine lamp lights up. It's pretty scary because it's kinda unpredictable and really weird sometimes especially in traffic. In some cases it's worse than others. For example the first time it happened I was driving home with it from the dealer on the back route and there was a little bumpy part where the street got replaced (should definitely not be a big deal for a car, right?) but then the cars RPM dropped under 1000 and the motor didn't really accelerate anymore and didn't really take the input from the gas pedal. The back way is downhill so I thought that it wasn't a big deal and I'll let it roll down to my home or very close to home and finally came to a stop at a bus stop. By that time also the Battery lamp was on and the servo was completely off. To my astonishment the car started up fine and i drove home. I thought at first that the battery was having shorts or the cables on the battery were loose but that wouldn't cause the motor to stall, right? I definitely ruled out the battery as a factor since in most other cases the Battery light wasn't on, only check engine. Is it bad that the battery is a little bit over 13V on the gauge? Just as a random question by the way.
Other than that it's an awesome car I just want to be sure so that I don't damage the car so I can drive it for many many more years!

Thank you very much in advance, I hope you can help me in any way

Martin

 

It's old gas! my did the same thing as yours. So try to run or drain all of that fuel out of the tank, and replace the fuel filter, put some Exxon or Texaco gas in her. and that baby should be good!

 

Oh and, i forgot to add this part in. it may be the Throttle Position Sensor going out. they only last 90.000 to 100.000 miles..

 

Hi,

Sounds like your Crankshaft Position Sensor - at the front of the engine picking up the crankshaft position from a cutout on the front pulley

There will be no fault code logged and there is no limp home mode on this item malfunctioning
Mine used to stall when coming up to junctions etc but would soon restart

If this is the problem it will get worse

I now keep a spare in the boot just in case

 

Hi - Thinking my XJ40 1990 model has same problem.....is the Crank position sensor something DIY? Been doing everything else to try and cure problem....when car heats up it will stall, but first start to exhibit a bogging sensation and lack of power. When cold car accelerates awesome ( especially with new plugs and no more oil leaks at spark plugs due to new valve cover gasket ). Usually it takes like 5 minutes to get it to start up and let me get home a few miles away.....not so good in a rush hour traffic situation...

 

Hi mike,

I fixed my stalling problem and what you are describing fits the problem i had. I assume the crank shaft sensor is the throttle body. If so then it is something you can do on your own. What you have to do is to clean the throttle body on the inside. If it has been driving for a long time there can be a gooey buildup and some carbon particles which clog the butterfly valve

Best regards,

Martin

 

Something just sprung to mind reading the last couple of posts of this thread. If the car runs fine when cold, yet stalls when it's warmed up or hot then it's quite possibly a sign of fuel pump failure. Classic symptom on '88's and '89's with the external fitted pump, not certain though with later models with the in tank pumps. Worth checking though.

 

Thanks for the feedback!

I have been driving the car and its been running great! But I did ask around and I am pretty sure its just a failing fuel pump. If it was the Crank Shaft sensor the car would not start up right away. Doesn't the sensor need 30 minutes to cool down?

 

I have a '93 Daimler and the cleaning of the throttle body solved my stalling problem (cold=fine, hot=stalling). What I encountered on mine however is that the Fuel gauge is constantly shifting. Meaning that the gauge shows sometims more fuel and sometimes less regardless of how I drive. At last a random question: The Oil pressure gauge shouldn't be close to zero when the car is standing still in D, right? And when I start to drive again the oil pressure goes up. I'm just thinking now that I wouldn't even have known if it would happen on my other car because my other car doesn't have an oil pressure gauge. Genius people at Jaguar to build this in!

Have a good Sunday, everyone!

 

Thanks to all who responded to my last post regarding my stalling issue.....I still am thinking Crank position sensor....when I am able to restart car; it still runs funny and I can feather the throttle to get a few miles to home with basically no power....maybe I refuse to believe it is the fuel pump....so I will investigate that. I know I had a similar problem on a totally different car ( 2002 VW ) and it turned out to be a dying crank position sensor. As for the other gentleman's post regarding oil pressure...mine hangs very low and sometimes the oil light goes on. As soon as I give it a little throttle it rises. I think the gauge is less than accurate....read somewhere else that might be the case.

 

Something else worth checking for is a leaking inlet manifold gasket. A leaking one will cause the same symptoms, runs well when cold, stalls when warm.

This is due to the ecu providing a richer fuel mix when cold but leans it off as temperatures rise. So leaks in the gasket will cause it to become even leaner leading to a stall.

 

Stalled again today, had to have it towed.

 

rolexmike:
You've already had a lot of ideas thrown at you, and I'm not sure if this has come up because I honestly didn't read all of the prior responses carefully. But... Five days into ownership of my '91, it began intermittently stalling until it finally gave up the ghost. I knew nothing about the car at that time, was not a member of any forum, and was in a state of panic. One tow and diagnostic bill later, the dealership ended up replacing the fuel pump RELAY and the car has never let me down since. It's an $11 part!

Don't know if it will be so easy for you, but it's worth a try. Swap one out from one of the secondary systems. I think it's located in the trunk on your '94 behind the carpet by the right taillight.

Cheers,
Scott

 

Thanks Scott, I will give that a try. The Jaguar is sitting at the repair garage right now.

 

Update?