XJ 1998 VM 2.5 turbo diesel - limp mode?
 

Hi
I've recently acquired an XJ 1998 VM for my son (he's on learner's, and I have a ZJ 98 4l petrol)
Car was reasonably priced (2k unregistered at 137000km)
However, got some weird problem, and I'd appreciate some advice (I've been lurking here for a while and can't figure it out)
Car runs nice, no smoke beyond first second when starting.
Revs to redzone and has a lot of pull in 1st and 2nd gear (AX-15 I believe).
If I go uphill in 3rd or 4th, would barely make it to 2100 rpm max
Checked #1, it's around 100ohms.
Dropped 100ml acetone in the tank, did some 100km ( short 4-20 km trips) seems marginally better.
Ran some liquimolly diesel cleaner through the throttle body...
Little improvement (maybe placebo)
When I accelerate in first, second, and even third (if not uphil), throttle pedal is very sensitive (sometimes jerks if I'm not operating the pedal very finely).
In 3rd or 4th, seems to loose any effect after depressing the first 1 cm or so... that's when it won't rev past 2100...
I also found ax gearbox had but a shade of fluid and was driven about 100km at least in that condition (effectively only with a coat if fluid in the gearbox)
If anyone has any suggestions, I'd really appreciate it.
As I've said, did a lot if research, read a lot of threads, none seem to fit exactly what I'm experiencing...
What would be your suggestion in progressively and methodically eliminating potential causes?
MAF?Pedal sensor? Fuel starvation? blocked cat?
thanks.
R

wrong section try posting over in the xj forums I am sure someone will try to help
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it has no cat
You have posted in the correct place. Ignore people who dont have a XJ diesel.
I take it you have replenished the gearbox oil. Probably will be ok as long as it is not making lots of noises.
Sounds like it needs a good service. Change all fluids ~ oils- engine, gearbox t/f case, diffs, brake fluid, coolant, & all filters- engine & fuel.
then see how it goes.
it may have a blocked fuel filter.
What is the throttle body you speak of? You could try blanking off the EGR.
What is with the acetone? as it is a strong solvent it could damage the electronics inside the IP. Dont use snake oils.
What is your location? Some times members can suggest people near to you who can help.

I've heard about the acetone being pored in diesel ...Myself never tried it .
But I do pour 200ml of 2 stroke oil in the fuel tank at every fill up.
It could be many things with your car but sounds like fuel related .
As Layback sugested check or change fuel filter (start with the easy ones),
Make sure there is no air /air leak or water in the fuel system.
Next would be to check the crank shaft sensor on the bell housing above the flywheel if not loose or faulty (unlikely but never know) .
Have a look at wirring if not rubbing against each other or chasie .
Check and clean the MAF sensor .
Pull the tank fuel supply hose of the fuel filter and blow in it to see if not blocked , should hear the air bubles in the tank .
It sounds like engine is starving for fuel . In the same time have a look at the sensor on the accelerator pedal and check for damage or wirring fault .
Worst ...it would be the IP but unlikely (quite robust).
A bit hard to pin point your problem . Hope you'll manage to find the problem and let us know .

Hi
Thank you fimor helping me
- I'm in Brissie area, Strathpine
- I think it does have a cat, unless it's a small primary noise dampener - it's just before the central locker
- you're right - not throttle body - I've sprayed into the intake manifold after disconnecting the hose coming from the air filter, layback40
- I do think might be a fuel delivery problem as you say, amlav
- I will try everything you gents posted as a logical step by step, engineering type troubleshooting

However gentlemen... Might have a bigger problem I need to kindly ask fir guidance with...
Last week I had a horrid and unexpected situation.
I have an AX-15, as I said before.
After replenishing fluid and changing after a week with 10w-40, took it for a spin to Bribie (Whorim) , about 100k round, both town and highway conditions.
Stopped there had brekkie and a leg stroll on the beach.
Drove back, about 3 k from home would not shift in 3rd or 4th, would grind and seriously kick the stick to the extent my hand3 would hurt.
Drove home in second. 1,2, easy as - 3 or 4 (tried double clutch and skip a gear) would grind and kick back big time.
Left it a couple of hours then went to the BWS to get some pack to drawn my sorrow, and shifted fine in 3rd . On the way back (it's 1km either way) stopped getting into third again.


Today (after a week) I went on the same round 2km trip to BWS, shifted like butter into 1,2,3,4,3,2,1 multiple times, zero issues, zero grind.

I'm puzzled... should I change the gearbox fluid again? I'm seriously at a loss. Both my son and I love the damn thing to pieces, but I don't know where to start with either power loss or this weird gearbox prob...

Could they be related?
Could it be fluid, syncros, clutch, clutch hydraulics?
Sorry to add to the list...

R

And yes, no noises on the tranny...

:o:rolleyes: It does not have a cat !!!!!!!!!!! If you looked at it properly you would see the thing you are looking at is a flexible joint. Probably you lack the knowledge to understand these things. The VM425 is not set up to take a cat. They didnt put cats on diesels back when it was built.

You need to have it properly serviced by someone who actually knows something about diesels. Best stop driving it until this is done. You run the risk of doing some serious damage.

Have you checked your clutch fluid level? This should have been done before you drove it.

You cant fix your jeep by posting on the internet. it needs to be looked at by someone with experience working on them. The diesel is completely different to the petrol ones. Like most XJ diesels that have been not looked after mechanically, yours needs a bit of trouble shooting & fixing.