xj vm 2.5ltr diesel Map senor issues

[anths]

Lpg injection is completely independent of the computer , it's mechanical requiring a boost signal ,in built delay timer .
Pressure .and quantity/ flow and time delay is set on the Dyno , product is called Eco shot.
unfortunately I never knew there was a issue until putting it on the road last week, I suspect it was in limp mode when I bought it and lpg masked the power issues by substituting fuel above 2000 rpm

Not sure if this was the correct method ,

I turned the ignition on with engine off, voltage tested at the map sensor :
Pin 1 Ground
Pin 2 3.2 volts
Pin 3 4.7 volts
pin 4 2.9 volts
temp out side was 10.3 deg C

Pin 2 and 4 seem a little high...?

What has been done so far:
New fuel filter
Egr disconnected
Turbo: checked No leaks , oil ect
Pipe work remove inspected clamps checked
New airfilter
fresh full tank of fuel
I can't get any basic fault codes doing the key thing I suspect I am doing it wrong have tried 3 times and 5 with nothing except km displayed..?

[amlav]

Originally Posted by layback40

You have the older update engine.
Does yours have an internal vac pump or does it have one on the alt?
They updated the engine part way through the update model.
You will also have the early Bosch engine management computer.

My vacum pump is a litle electric pump just behind the ECM and controled by the ECM . Hmmmm...seem to be original setup and maybe just another variant

Anths....unfortunately don't know anything about the lpg injection on diesel systems...I heard of it but that's about all .
Definetly sounds like your engine is in limp mode when on diesel .
You mentioned that once fixed the leak in the turbo rubber pipe it went ok for a short time . Did you manage to find out why ?
Just thinking that lpg being a dry sort of fuel could have jammed the no.1 injector sensor needle inside tough mesuring it still shows ok but mechanicaly
maybe jammed . After all the diesel fuel also lubricates in the same time .
Cheers.
Andrei

[layback40]

Originally Posted by anths

Lpg injection is completely independent of the computer , it's mechanical requiring a boost signal ,in built delay timer .
Pressure .and quantity/ flow and time delay is set on the Dyno , product is called Eco shot.
unfortunately I never knew there was a issue until putting it on the road last week, I suspect it was in limp mode when I bought it and lpg masked the power issues by substituting fuel above 2000 rpm

Not sure if this was the correct method ,

I turned the ignition on with engine off, voltage tested at the map sensor :
Pin 1 Ground
Pin 2 3.2 volts
Pin 3 4.7 volts
pin 4 2.9 volts
temp out side was 10.3 deg C

Pin 2 and 4 seem a little high...?

What has been done so far:
New fuel filter
Egr disconnected
Turbo: checked No leaks , oil ect
Pipe work remove inspected clamps checked
New airfilter
fresh full tank of fuel
I can't get any basic fault codes doing the key thing I suspect I am doing it wrong have tried 3 times and 5 with nothing except km displayed..?

Those readings are possible. I would have liked to see 5v on pin 3 as its the 5v supply IIRC. If you got open circuit, I would be concerned.
The key thing doesnt work on updates.
When they installed the LPG, they may have done something to it.

[layback40]

Originally Posted by amlav

My vacum pump is a litle electric pump just behind the ECM and controled by the ECM . Hmmmm...seem to be original setup and maybe just another variant

Anths....unfortunately don't know anything about the lpg injection on diesel systems...I heard of it but that's about all .
Definetly sounds like your engine is in limp mode when on diesel .
You mentioned that once fixed the leak in the turbo rubber pipe it went ok for a short time . Did you manage to find out why ?
Just thinking that lpg being a dry sort of fuel could have jammed the no.1 injector sensor needle inside tough mesuring it still shows ok but mechanicaly
maybe jammed . After all the diesel fuel also lubricates in the same time .
Cheers.
Andrei

That vac pump is for the EGR only. Its not the main vac pump. If you dont have a vac pump on the back of your alt, you have an internal one. You could try following the big vac line from your booster over to the other side of the engine & see where it goes.
The sensor doesnt have its own needle, it senses the pintle needle moving & if it wasnt moving the engine would not be running on all 4.

[anths]

Installed a new map sensor today and "bingo" I have atleast 3 times the power and torque I had before on lpg , boost pressure now snaps around to 16psi and holds on the gate , I was impressed with the performance on lpg before, now diesel is mind blowing and lpg is insane .
How quickly this jeep gets up to speed ,I couldn't wipe the smile from my face It drives not like a 4x4 but a massive car I haven't even switched the lpg back on !

Massive Thankyou to all who helped with suggestion

Best regards Anthony

[amlav]

Originally Posted by layback40

That vac pump is for the EGR only. Its not the main vac pump. If you dont have a vac pump on the back of your alt, you have an internal one. You could try following the big vac line from your booster over to the other side of the engine & see where it goes.

Yep , you right the main vacum line seems to start just under the alternator as far I can see . Now that I had a look for the vacum line I've also discovered that the intercooler hose is rubing against the power steering pipe's.

anths
Hope you'll enjoy you diesel for a long time .
But might as well just a piece of advice . Diesel engines vibration is much more pronounced than on a petrol one and worth from time to time to check hoses and electrical wiring for possible damage due to rubing against chasie or engine .
Cheers,
Andrei

[anths]

I will do that for sure ,
Im taking the jeep for a shake down trip later in the week when I get back I will install the water / methanol injection I had installed on my last diesel .
Since I'm happy with the power levels I will be running a higher water ratio than methanol to drop exhaust temps down

Just a side note: I noticed my Vm diesel engine has a ball bearing turbo fitted , I must admit I'm happy not having to worry about the bearings wearing out !

Cheers Anthony