Topic: Need help with my 2.5td XJ (Read 5346 times)

joelypops · « **on:** August 07, 2012, 03:11:01 PM »

Afternoon all... I need some help with my 1997 2.5td cherry, and before you all scream get rid of it the problems not with the heads (for once)

Its got itself stuck in limp home mode ( i think ) - doesnt want to rev past 2000rpm just wondered if there was anything obvious to look at before i start throwing even more money at this thing!

also, the speedo and cruise control havent worked since i got the jeep last year. finally got myself a replacement speed sensor, bolted it in and still not working. Just wondering if anyone knew where the cables go or if there is something else i should be looking at first.

and lastly, i pulled the cover off of what i think is the ecu plug (left hand side of the engine bay) and found this:

[attachment=1]
[attachment=2]

these two cables look like they have been cut but may have been pulled out.. does anyone have any idea what they are meant to be doing???

sorry for the long thread and thanks in advance for any advice!

Cheers,
Joel.

Dave69 · « **Reply #1 on:** August 07, 2012, 05:58:12 PM »

They look lile power supply cables by the size and colours. Have you checked the. vacuum cannister for leaks as this appears to be linked somehow in the cruise control system. Also check the air intake hose as the internal support coil does collapse with age allowing the hose to collapse as the turbo cuts in (@ 2000rpm)

Sent from my LG-P970

Dutch · « **Reply #2 on:** August 07, 2012, 07:02:54 PM »

Dunno if its a comparable system as the WJ but had abs light come on last year and cruise did not work.

Diagnosis ABS Ecu duff. Replacement ECU off the bay, dealer install, and all's good.

The Smiths · « **Reply #3 on:** August 07, 2012, 07:07:11 PM »

for limp mode check resistance of No1 injector sensor - should be around 97 ohms - if 0/infinity it is shot and would cause it...

They are usually killed when someone cleans the engine

scrw · « **Reply #4 on:** August 07, 2012, 07:09:04 PM »

also check your turbo hoese haven't colapsed internally

joelypops · « **Reply #5 on:** August 07, 2012, 09:07:34 PM »

cheers for the replies so far, just checked no.1 injector and i've only got 2ohms resistance, which leads me to my next question; anyone got a good no.1 injector for sale!?

Cheers,
Joel.

Dave69 · « **Reply #6 on:** August 08, 2012, 10:27:31 PM »

they are horredously expensive. search for VM specialist on google as they will be able to help.

another option is to fit a resistor in on of the wires to fool the system while you source a replacement

joelypops · « **Reply #7 on:** August 09, 2012, 09:40:06 AM »

Quote from: Dave69 on August 08, 2012, 10:27:31 PM

they are horredously expensive. search for VM specialist on google as they will be able to help.

another option is to fit a resistor in on of the wires to fool the system while you source a replacement

I used vm specialist earlier this year when the heads cracked. Messed the order up, messed the refund up and sent me a bad head.. trying to avoid them now really.

I like the idea of the resistor, roughly what size resistor should i put in and where should it go? Accross both terminals in the plug or just inline one of the cores?

Cheers,
Joel.

bigjeepzj · « **Reply #8 on:** August 09, 2012, 09:58:35 AM »

90/100 ohm resistor in line with one of the cores could work

maplin do a 100R 10 watt part no. H100R for 79p worth a punt

joelypops · « **Reply #9 on:** August 09, 2012, 12:07:58 PM »

uick update, i tested the injector again this mirnibg and i now have 110.3 ohms resistance

but its still not pulling past 2000rpm.

I pulled the fault codes off the dash but cant fibd anywhere that will tell ne what they mean..

I got

55
27
16
43
36
13
55

Quite a nice list eh!

Cheers,
Joel.

JamesH · « **Reply #10 on:** August 09, 2012, 04:08:00 PM »

http://www.birtydastards.com/frm/index.php?topic=6278.0

joelypops · « **Reply #11 on:** August 09, 2012, 05:56:35 PM »

brilliant link thank you!!!

so, that means

27 Injector circuit isn't switching when it's told to (TBI)
OR (MPI) injector circuit #1 not switching right
OR (turbo) injector circuit #2 not switching right
OR (all 1990-) injector output driver not responding
- check computer, connections

16 Loss of battery voltage detected with engine running

43 Peak primary coil current not achieved with max dwell time
OR
43 Cylinder misfire
OR
43 Problem in power module to logic module interface

36 (turbo only) Wastegate control circuit open or shorted

13 MAP sensor or vacuum line may not be working

how does the wategate circuit work on these?? i guess it does kinda feel like the turbo comes on for a second then drops off, as if the wastegate was fubard..

Dave69 · « **Reply #12 on:** August 09, 2012, 09:12:37 PM »

the problem with engine code lists is that most of them are a result of one failure.

solve code number 27 as you may have a break in the connecting wire, these wires are typical italian wiring, they go brittle with age.

error 13 is linked with your lack of cruise control

error 36 is more likely a result of the limp home mode or reduced power setting

joelypops · « **Reply #13 on:** August 10, 2012, 07:51:45 PM »

ok, i re-terminated the two broken wires into the big multi plug and i now have a working speedo!

cruise control is also working now!

I still get the same error codes and its still in limp mode though so im not out of the woods yet.. going to have a look tomorrow at the injector wiring. where do they go? straight back to the plug in my first pics??

Cheers,
Joel.

The Smiths · « **Reply #14 on:** August 10, 2012, 08:30:05 PM »

did you clear all the codes??? - if not they will stick there

joelypops · « **Reply #15 on:** August 10, 2012, 09:29:34 PM »

I didnt think they could be cleared without a scanner??

Dave69 · « **Reply #16 on:** August 10, 2012, 10:08:27 PM »

There is a proceedurebut they should clear themselves after a number of key on start and stops.

joelypops · « **Reply #17 on:** August 21, 2012, 08:26:25 PM »

ok, quick update.. thinking now it was just some bad fuel or slightly blocked pickup etc as i put fresh diesel in monday morning and it now runs sweet as a nut!? was running real rough and sluggish friday night then left standing over weekend. who knows, at least its running better!!

Cheers for all your help anyway guys!

Dave69 · « **Reply #18 on:** August 22, 2012, 10:47:02 PM »

have you drained the fuel filter as some of these have a water seperator. unscrew the knurled button on the base to allow the water out until diesel starts to empty then shut.

Tomxjvm · « **Reply #19 on:** February 23, 2019, 09:40:33 AM »

Hi, i also have an xj 2.5 vm diesel. I've searched so many forums regarding cruise control. When it was new the dealer robbed the cruise control off it. I have installed the cruise control clock spring and switches but still cannot get it to work. Does anybody know what else I need?
I know the petrol 4.0 type has a cruise control servo. My XJ has an electronic fuel injection pump. So im not sure if it takes the servo or not.
Any help is appreciated

Cheers

XJ Fan · « **Reply #20 on:** February 23, 2019, 11:52:12 AM »

Quote from: Tomxjvm on February 23, 2019, 09:40:33 AM

Hi, i also have an xj 2.5 vm diesel. I've searched so many forums regarding cruise control. When it was new the dealer robbed the cruise control off it. I have installed the cruise control clock spring and switches but still cannot get it to work. Does anybody know what else I need?
I know the petrol 4.0 type has a cruise control servo. My XJ has an electronic fuel injection pump. So im not sure if it takes the servo or not.
Any help is appreciated

Cheers

If you start your own thread (instead of resurrecting a seven year old one), then I'm sure you will get more attention. Unfortunately, I know nothing of how the cruise control works, so cannot assist.

Author Topic: Need help with my 2.5td XJ (Read 5346 times)

joelypops

scrw

joelypops

joelypops

joelypops

joelypops

joelypops

joelypops

joelypops