XJ99 Turbo diesel advise please

[amlav]

First question....
On my xj turbo diesel there is a sensor right after the air filter box on the plastic air duct going to the engine. Pulled the wiring harnes plug of it to see
if any fault code pops up with engine running....and there was none and no difference in the idling rpm and no or light puped up either.
What is that sensor and what does it do......turbo booster sensor ???
And where can i buy it in Melbourne beacouse I've droped it and some litle
ceramic resistors broke of it.
Second question...
Where can I get new turbo hoses from the turbo to intercooler and back for this xj.
Cheers,
Andrei

[Deezelweazel]

lol-it is the boost and air intake temperature sensor. NO boost, NO difference during idle.
that tiny item at the top is the temp feeler. If you are lucky you are only missing the tip. Expect around 100€ at the Bosch dealer.
These Intercooler hoses are extreme expensive- expect around 900(!)€ at the stealer.
By the way: how are you gonna read faults in this engine? You need a Chrysler specific OBD II T reader. price around 7000€-if you are lucky to get it.
The old fashioned ignition turn on-off method does not work in this engine.

another good hint in my opinion- don't do that connect-reconnect thing during a running engine again. The electronics (ECU, PCM) are ESD sensitive. you won't get cheap replacement. We talk about high dollars. You can buy a complete used xj for that unit.
Ok, it's your stuff. But you see what happens, if you mess with electronics. There are no adjustable or better parts you can tune by yourself. always turn the engine off and disconnect the battery minus before you work on board.

[amlav]

Thank's Deezelweazel for your replay.
The codes can be read out by the on-off method and even the book mention it at least it showed the battery disconected 12 as i remember and 55 which is the no fault codes.
It seems to be OBD1.
Yep ..only the tip of the sensor is broken. I've reinstalled it and i'll try it out later on today to see if it makes any diference.
Turbo hoses....hmmm...sound verry pricey ..is there any other option ??
Cheers,
Andrei

[Doctor W]

Originally Posted by amlav

Thank's Deezelweazel for your replay.
The codes can be read out by the on-off method and even the book mention it at least it showed the battery disconected 12 as i remember and 55 which is the no fault codes.
It seems to be OBD1.
Yep ..only the tip of the sensor is broken. I've reinstalled it and i'll try it out later on today to see if it makes any diference.
Turbo hoses....hmmm...sound verry pricey ..is there any other option ??
Cheers,
Andrei

Just one point for your information:

If it's a 1999 model it will be OBD2.

[amlav]

Maybe it is 97 XJ but the rego paper shows 99.
It had the engine replaced by previous owner. Would that make
any diference ???
Definetly got 2 digit codes which I assume is OBD1. The OBD2 codes are 4
digit as far I know (could be wrong tough).
Anyway , drove it tooday and there seems to be no diference in power and speed .Pushed it up to 140km/h and all sounds normal. Can hear turbo winding
up ok.
Can anybody explain to how and what that booster/temp sensor suppose to do and what would be the way to check it out if it works or not.
Cheers,
Andrei

[dxj]

Hi,

If yours is 97, 98 or 99 XJ I think it may have a VM "425 CX1" engine with the mass air flow (MAF) sensor in the 'lid' of the air filter box. Post 99 XJ I think have VM "425 CX2" engine with Manifold Absolute Pressure (MAP) sensor in the top of the intake manifold.
Same purpose:- to help the engine computer get the fuel mix and injector pump advance right amongst others. Not sure if it affects EGR operation?

If damaged, it may still be okay, or you may not notice at normal operating temperature and conditions as the engine computer will possibly "estimate" for a non active sensor. Will probably be more noticeable under extreme operating conditions and perhaps fuel economy may be affected.

Good Luck

[murray]

ok i have sat and watche this as above dxj says
2 types of engine
97/98 air sensor in air box type 2 99 on sensor is on top of inlet manifold
different systems
the hoses i repaired mine by cutting the dammaged piece out of it abnd fitting a tube inplace that had rolled ends to stop blowing off