2.5 diesel power loss 1900-2000rpm

[grandpa_spec]

My xj diesel ran out of fuel the other day I got a major service done on it and now it makes no power after 1900-2000rpm

[layback40]

it sounds like the dreaded limp mode !
First off disconnect your battery over night & see if that fixes it.
Next check the resistance of the sensor on #1 injector. will need to disconnect the lead at the plug near the fuel filter. It should be about 100ohms.
If that is good, probably time to get jeep to plug their DRB11 computer onto the OBD2 socket & look for engine faults.

[grandpa_spec]

cheers!! will disconnect

[grandpa_spec]

disconnected, still no luck :(

[grandpa_spec]

Will a.scangauge 2 scanner work on a 98 2.5

[mud_slut]

Will a.scangauge 2 scanner work on a 98 2.5

it should its OBDII compatible

[layback40]

disconnected, still no luck :(

With it disconnected you are supposed to use a multi meter to check the resistance of the sensor.

[layback40]

it should its OBDII compatible

No. to get engine faults on a 2.5 turbo diesel you need the Chrysler computer.
OBDII will not show codes for the Bosch ECM. There are other threads concerning the diesel & codes on this site. It is not the same as the petrol engine.
You may see some codes but not the ones you need.
Once the OP has done the resistance test on his #1 injector, he can proceed. Given the the disconnect didnt make any difference ( it didnt get worse) it is likely its the injector sensor.
How do I know? I had this exact same problem at the start of the year & so have others with diesel XJ's.

[grandpa_spec]

came up fault when it ran out of fuel, cleared computer all good now !

[layback40]

came up fault when it ran out of fuel, cleared computer all good now !

Good to hear ! You got off lightly.
I didnt know they went into limp mode following running out of fuel.

[Balkanac]

i ran out of fuel 4-5 months ago and the only problem i had was to actually start the thing. The RAC ute came, hooked up the jumper cables and a battery pack on top and then it started. But ran fine after that

[Turismo07]

came up fault when it ran out of fuel, cleared computer all good now !

Can't believe it threw a fault after running out of fuel...

How did you clear the computer?

[grandpa_spec]

put it on an odb scanner and cleared it

[Turismo07]

put it on an odb scanner and cleared it

Do you mean a OBD2 scanner? If yes, then I'm amazed as everyone says that the VM diesel can only be read by a 'DRB' scanner and only Jeep dealerships/wealthy mechanics have these...

Thanks

[MidnightMods]

I check/clear and data log via a cheapie bluetooth (8 bucks or so ) obd2 and either my phone or nexus 7 tablet.
2.8lt vm 2010jku

[layback40]

I check/clear and data log via a cheapie bluetooth (8 bucks or so ) obd2 and either my phone or nexus 7 tablet.
2.8lt vm 2010jku
Yours has a different engine management system.
The XJ 2.5 has a Bosch ECU that doesnt talk OBD2.
Its like trying to use windows on an old apple.

[grandpa_spec]

i bought a scan gauge 2 and it reads nearly everything on it

[amlav]

My xj 2.5 vm diesel /year 2000 definetly is not OBD 2 compliant as the only thing I can get from it is the supply voltage.Hooked it up to an ELM bluetooth scanner and tried 3 different software on my laptop and got connection but no other data except voltage reading .
Sent some ATxxxx commands to try and get some hex values back from ECM
but not much luck . Got some eprom hex dump with one of the commands but
dont know the meaning of each hex digit returned but definetly not an OBD2
control module. Even tried different protocols .. .
Sooo... I'm a bit puzeld of how a ScanGauge (that is OBD2 anyway) was able to read the codes and clear them.
Can you give us a bit more details and the model of the ScanGauge reader.
Cheers,
Andrei

[cheezel]

Hi Andrei,
I have a eBay cheapie elm type Bluetooth scan tool. It reads/clears PCM codes and I can get info using software on the laptop or the torque app on android. (eg fuel consumption/rpm etc)

My understanding as others have posted earlier is that you need the DRBIII scan tool to get full diagnostic of the engine. The jeep PCM is made by Motorola (as I understand it) and the ECU/ECM is Bosch. Thus the OBD tools have access to the PCM but not the ECU.

This means that you might have a PCM fault that can be viewed cleared with an OBDII compliant tool, though equally likely is that there are codes that you can't see to read and know their existence without the super expensive DRB tool.

Hope this helps?

Cheers!

[dgmm]

hi, can anyone confirm or deny that there are more than one type of limp mode? I am having trouble getting power from my 2000 TD, flat out itll just do 100kph! foot to the floor 5th gear and instantaneous fuel consumption sits at 10l/100. While trying every test/fix I could find I disconnected both temp sensors which put it in true limp mod, ie. it basically wouldn't even rev above 2000rpm. so I spose my question would be the lack of power im experiencing, is it likely to be a limp mode or fuel/ air related. muchly appreciated

[Mudmonster]

hi, can anyone confirm or deny that there are more than one type of limp mode? I am having trouble getting power from my 2000 TD, flat out itll just do 100kph! foot to the floor 5th gear and instantaneous fuel consumption sits at 10l/100. While trying every test/fix I could find I disconnected both temp sensors which put it in true limp mod, ie. it basically wouldn't even rev above 2000rpm. so I spose my question would be the lack of power im experiencing, is it likely to be a limp mode or fuel/ air related. muchly appreciated

if your jeep is going over 2000rpm with no dramas its not limp mode.
the lack of power could be a number of things.
a dirty air filter, old/dirty fuel filter, boost leek (intercooler pipe) or a blockage in the exhaust, (muffler or a bent pipe)

mine used to be quite slow and sluggish, until I replaced the exhaust, i think there was a blockage in my muffler.

it you want to eliminate the exhaust, you can unbolt your exhaust at the dump pipe and take it for a run and see how it goes. it will be loud and sound like a tractor. ;)

hope this helps

[grandpa_spec]

Mine was a fault code ,just took it to a place that had an odb scanner and they cleared it, good as new

[The Smiths]

Mine was a fault code ,just took it to a place that had an odb scanner and they cleared it, good as new

Good for you - but this does not help the OP as OBD port will not reset engine management on an XJ diesel....

[dgmm]

hi, thanks for the quick replies,

was just asking about the limp mode/modes because I'd seen a post elsewhere saying they had a number of limp modes depending on the fault.
ill continue down the path of fuel/ exhaust as I've tested number 1 resistance, new air/fuel filter, bled air from fuel, new fuel lines etc. etc.
this is the first jeep I've had and realise they aren't a powerful engine so I don't have anything to compare it to. I bought knowing it was lacking power but with only 100000ks on it figured I cant go too wrong. as a rough guide what would be the top speed, (without being silly) or put your foot down at 100 what L/100 would it show.

I'd send it to a shop to get tested but cant find anyone whose heard of let alone knows anything about these motors. or they are as helpful as tits on a bull and don't want to help!

thanks again.

[Mudmonster]

it should comfortably sit on 110-120k with some more acceleration to go.

mine running 33's sits on about 13L/100k (average consumption)
instant fuel could vary, think mine flat to the floor at 100k it goes up to about 30L/100k maybe more, but I wouldn't take much notice of that gauge

[dgmm]

cheers, gives me an idea at least of what I can expect, I drive everywhere flat foot to get 100 maybe 105 and fuel economy sits at about 10.0 will keep looking.

[mud_slut]

cheers, gives me an idea at least of what I can expect, I drive everywhere flat foot to get 100 maybe 105 and fuel economy sits at about 10.0 will keep looking.

That's not too bad my missus has a brand new bt-50 and that will sit around 9.5 at 100 mine is playing up a bit and will sometimes sit around 9 and sometimes sit around 13 but that's a different story. If you are worried about errors I believe there is a trick with turning the car on and off in a sequence to display and stored error codes.

If this doesn't show anything a look under the hood may help looks for diesel leaks around the injectors and injectors lines. When I first bought my xj one of my return lines was leaking diesel furiously. A quick trip to enzed / autobahn can fix the problem.

[Mudmonster]

That's not too bad my missus has a brand new bt-50 and that will sit around 9.5 at 100 mine is playing up a bit and will sometimes sit around 9 and sometimes sit around 13 but that's a different story. If you are worried about errors I believe there is a trick with turning the car on and off in a sequence to display and stored error codes.

If this doesn't show anything a look under the hood may help looks for diesel leaks around the injectors and injectors lines. When I first bought my xj one of my return lines was leaking diesel furiously. A quick trip to enzed / autobahn can fix the problem.

you turn the key on, off, on, off, on, off, on and numbers will appear where the K's display. 55 will mean no errors.

[mud_slut]

Thanks MM. I knew it was something like that

[dgmm]

Yeah definitely not leaking fuel, but starting to think it's sucking a little air into the fuel.
As for key trick, I was told hold down odo reset while turning key to on, however mine simply runs through a series of gauge checks and odo runs through 1111111 - 2222222 - 3333etc. It doesn't give any codes, not even 55...

[Mudmonster]

Yeah definitely not leaking fuel, but starting to think it's sucking a little air into the fuel.
As for key trick, I was told hold down odo reset while turning key to on, however mine simply runs through a series of gauge checks and odo runs through 1111111 - 2222222 - 3333etc. It doesn't give any codes, not even 55...

that trick is just to check all the gauges are working

the on off one will give the codes

[dgmm]

I just tried on off and got nothing. Is it all the way back to lock or just back one pos from on?

[Mudmonster]

I just tried on off and got nothing. Is it all the way back to lock or just back one pos from on?

back to lock then on position, 3 times

[layback40]

you turn the key on, off, on, off, on, off, on and numbers will appear where the K's display. 55 will mean no errors.

I have never managed to get it to work on mine MM. Makes me think the last of the XJ diesels have a different opperating system.