Guy from Sweden with smokey Cherokee XJ VM 1998
 

Fellow Jeepers

New to the forum. Have a problem with my Cherokee (eu model) XJ VM 2.5 1998 (Turbo Sport). Im from Sweden and my "daily driver" needs some expert help. I have been to the forum several times but it is still hard to get answers.

Everything work just fine except emission failure and black smoke when revving up to 3000-4000 rpm. Check engine lamp is not on. Guessing the old Jeep gets too much diesel (?) It passed the emission control 1 year ago but now its like a coal mine ;)

This is what I have done so far:

Oil change. Over a year since last time so I did kind of a oil-flush (oil change x 3 + oil filter in a short period of time) I also used a engine additive before the last oilswap.

Air filter swap done.

For some period now I have used diesel additives that should clean the fuel system and CAT.

Found some oil leak around the intake manifold and ERG valve. Cleaned all the parts up and put it all back together.

Cleaned the MAF. Trying to measure it with a multimeter and is not 100% sure if its ok or if I did it the right way. When I pull the wires off the MAF when the engine is running nothing happens at all. No stalling or change in REVs. Is the engine supposed to stop when doing that? Seems to be the case i some cars.

I tried to do a vacuum/air leak test but did not find anything obvious. Maybe I should buy a special tool for this?

This i what I'm thinking:

Some air/vacuum leak anyway?
MAF sensor failure?
Turbo fail? Sometimes the engine makes a “rattling” sound when idling.
Leakage between the turbo and engine?
Injection pump failure?
or…. is it “the classic” no 1 injector??? Have not checked that yet. Did a engine wash some seeks ago and now I can see some new "black stuff" around the 2 injector closest to the front.

Well Im joining the forum here and hope someone can help me. Ill send a link to some pics next time

Have a great day. Cheers / Thomas

Have you checked the glow plugs are working properly? as you say it's rattling sometimes on idle? Maybe not firing all cylinders? .. what about fuel filter? I change mine every time I do an oil change (every 10000k or at least every 6 months) .. first injector should be fine if you are reving fine .. first injector issue causes limp mode and loss of power at 2000rpm ... if your glow plugs are on the way out this could cause black smoke?? Maybe another jeeper could verify that (@Layback 40??) .. either way great to have you join Ajor! Great community here plenty of knowledge and expertise.. pretty confident you'll find the issue with advice on here

Sent from my SM-G930F using Tapatalk

Welcome.
From your description, you have the early VM with a MAF (near the air cleaner), the later ones have a MAP on the top of the inlet manifold.
A MAF is just a series of wires in a grid in the air flow path. If you remove the pipe off the air box you can inspect it. The wires should be clean. when dirty it should cause lean mix so no smoke.
If your #1 injector sensor fails it will limit you to about 2,000rpm. it wont cause smoke.
You dont state mileage, that makes it hard!
worn out injector tips can cause smoke but normally at idle. A bottle of injector cleaner & an Italian tune (google it)normally fixes it. Make sure you find a good uphill stretch of road for it ~ WOT & let it work ~ 120km/hr for as long as you can.

3 things that will cause smoke

1/failed turbo seal. If you take the outlet hose off the turbo & there is oil every where & you can wobble the turbo fan up & down, then the seal in the turbo body is bad.

2/ Failed EGR. If you remove the AGR & are able to blow air through from the inlet (pipe) side it is failed. Simple fix is to put a blank plate ( piece of tin can) between it & the inlet manifold.

3/ Rings. If when warm & idling, you unscrew the oil filler & it blows off in your hand (high crank case pressure) it has a ring problem. if it just dances for a second & then falls to the side, all good.

Hope that helps

Also, there is a VM Diesel group on facebook & the guys running the group are local to you.

Thanx for replying. Yes. I think this is a great forum. Been here many times before I signed up.

OK. I edited this post a little bit. BTW I found a service manual (1700 page one) ;)

OK. Ill continue here then. Added some pictures and YT links…………..
and https://sites.google.com/view/jeepch...m25l/startsida

IT (the JEEP) have been rolling around 260000 km or 161 556.51 miles

Looked at the ERG/turbo once again. Going to unbolt the turbo tomorrow looking for oil leaks and fan wobble.


I have 1 concern tho (pic). Seems to some kind of oil connection on the tubo. Its leaking oil. Any thoughts on that?

[IMG]http://i.imgur.com/QjRaUBB.jpg?1[/IMG]



NO problems taking the oil filler cap off. Nothing happens


As I said before. It starts up and drives normally (IMAO). When the engine is “cold” one can clearly hear some kind of strange engine noise.

https://youtu.be/KsqAvoP_iLE

When IT is warmed up there is no rattling noise. Therefore (IMAO) no problem with the injectors or glowplug (?)
https://youtu.be/yBqp7khCLgc

Look at the black smoke when revving up. Haha, WTF (??). This is the main problem I guess.

https://youtu.be/m8p9HiRbT-U

About the MAF sensor. Can’t find any small wires (pic). Something missing here??

[IMG]https://i.imgur.com/2XE3Bau.jpg?1[/IMG]


and finally….. Found some pictures when I changed the fuel filter. It’s upside down… A classic nOOb mistake. Is that the problem?

AND when i bought IT 2-3 y ago the horn "beeped" everytime I locked the door. The "beep" is now gone. NOT a big issue (the door lock works) but I just thyought I inform u all about that.

[IMG]https://i.imgur.com/pFzgU9U.jpg?2[/IMG]

Damn. Maybe its the diesel filter :oops:

Well. In my opinion there is probably nothing major with the old JEEP. Some kind of ez fix IF I can find it.

/ Thomas

If you want lots of help you need to learn how to post pics on here, not just links to other places. One of the links doesnt work for me. The engine will continue to run (in limp mode) without the MAF connected.
There is an oil supply line to the top of the middle bit of the turbo & a drain line under back to the sump.

NO problems taking the oil filler cap off. Nothing happens ~ please go back & read exactly what I said.

[QUOTE=Irie;1632944]Thanx for replying. Yes. I think this is a great forum. Been here many times before I signed up.

Before I continue. How can I get a hold of a sevice manual for my JEEP? I have searched for many hours. Does anyone here got one for sale or to download.

QUOTE]

try here, I free downloaded MANY Jeep manuals

http://www.greatlakesxj.com/tech.html

also the NAXJA site maybe?

to post pic, try Imgur,,,free & very easy to use

Haha, ok. Ill try greatlakesxj.com and will do better on pics. Sorry about that

I doubt the great lakes site can help as the diesel XJ was never sold in the USA.
You should be able to purchase on ebay a manual on CD that includes the diesel. Thats what I did years ago.

AND when i bought IT 2-3 y ago the horn "beeped" everytime I locked the door. The "beep" is now gone. NOT a big issue (the door lock works) but I just thyought I inform u all about that.

[IMG]https://i.imgur.com/pFzgU9U.jpg?2[/IMG]

Damn. Maybe its the diesel filter :oops:

Ok for the horn beep when unlocking.. read up in the owners manual you can turn the horn beep on or off when using the remote central locking .. from memory think its like holding the lock button down for ten secs to activate or deactivate the twin beep of the horn

The diesel fuel filter has the writing upside down in your pic but you cannot install it upside down the filter screws on only one way and the water catchment bowl with the heating element on the bottom can only attach to one end too .. you should change the filter..you haven't done it in a while or ever before if you think it's upside down haha .. how many ks since last filter change??

Sent from my SM-G930F using Tapatalk

Injectors are cheap to check and rebuild in your side of the world, as they are mostly standard Bosch indirect injection injectors, same construction as the Mercedes versions.

Do you have smoke under load? Do you hear any air rushing from a broken intercooler hose?

Just looked at the video clip with the smoke . Is not too bad . I would change injectors or try the injector cleaner additive .
In time spray pattern of the injectors can deteriorate due to nozle clogging up or enlargement of the small nozle holes and fuel doesn't burn as good as when injectors are new .
Unburned fuel or over fueling will create the black smoke you are having .
If there is air leak in the turbo/intercooler & hoses area than there will be less power and by pushing the accelerator harder to get more power it creates an over fueling condition and will show as a black smoke .
Carefull with the MAF sensor... it has a ceramic tip in it (you can see it in your picture) and it breaks very eazy .(ask me how I know) and are sooooo....expensive.
Just spray it with a Maf cleaner and should be enough .
The tube that goes in the turbo is the drain oil return in the crankcase .
The beep problem can be fixed as advised by others .
Not to sure about the rattling noise . Don't think would be the crankshaft big end bearings . Could be still injectors related .
Hope this help you a litle bit and welcome to the forum .

Hello there and thanx for the replies.

So, this is what I did ...

1. I checked the turbo. There seems to be no oil leak and the fan does not wobble.

[IMG]http://i.imgur.com/Dm0EOky.jpg?4[/IMG][IMG]http://i.imgur.com/XP9qXXT.jpg?1[/IMG]

2. It seems to be a small leak in the ERG from the inlet pipe side. The little valve seems to be leaking a little. Need a new ERG valve I guess (?) Im blocking it with a blank plate at the moment. I guess I will NOT pass emissions test this way (?)

3. Also found some small leaks from the inletpipe going in to the engine and No 1 glow plug

[IMG]https://i.imgur.com/EKZ6280.jpg?3[/IMG][/IMG][IMG]https://i.imgur.com/EmtgMMY.jpg?2[/IMG]

4. Crank case fail (??) No high pressure from the oil filler cap when the Jeep is warm and idling

@ Jamunji - Fuel filter was changed like 8 month ago. OK, Ill look into the horn thingy when I learn german and read the german instruction manual.... ;)

@ Adrian - NO excessive smoke under load. Just when revving up to 4000. NO obvious air leaks from the intercooler. Just a vague "leak noice" from the left wheel area. I think it is fuelpump working just fine (?)

@ amlav - I have tried injector additive for some time now. Maybe its time to change the injectors. I fixed the "drain oil return" connection. It does not leak anymore. Ill fix the BEEP thingy later ;)

Sorry about the long thread. Im not gonna give up anytime soon.

BTW I found a 1700 page service manual ;)

Was the service manual on CD?

No need to say sorry for long thread, we like long threads with lots of information in them.

For getting it passed the test, if you disconnect #1 injector sensor does the smoke stop? If it does, you could do that & reconnect after the test. If VW got away with it for years, so can you!

Leak on GP will either be the rocker cover gasket or the GP not sealing. Try tightening the front rocker cover hold down bolt & removing, thread cleaning the GP & reinstall with some anti seize paste on the thread.

ERG only impacts NOx, do they test for that? It is only supposed to open when the engine gets hot during high load conditions. I dont think the test would have this happen.

Hello again


Fixed the no 1 glowplug. Cleaned the treads and put it back. It does not leak anymore ;)

Have to get a special tool to remove the no 1 injector...

I found the service manual on another forum. Someone had a PDF file. 1724 pages long

Tried to remove the no 1 injector sensor. I can still see some smoke but the problem is that I can not measure it (the emission).

I also tried a "ERG delete" (a plate over the valve). Same problem. I cant measure the emission.

Im probably going to turn IT in to a Jeep shop so they can measure things up.

Found this page on the the net today. Haha there could be a lot of issues with my Jeep I guess - https://www.pfjones.co.uk/troublesho...el-engine.html

Question. Is it possible to measure air/vacuum leaks with a vacuum gauge AND then, what vacuum hose should I connect the gauge to?

What is the best way to remove the serpentine belt. I believe the berrings in the altenator is failing, therof the strange sound from the engine bay.

Til next time.......

You cannot remove the sensor! You just unplug the wire at the connection to the loom.
A long reach 12 point socket can be used to remove it. You feed the wire down a point that is in the middle of the flat on the injector.
The EGR blank off plate goes between the EGR & the manifold extension.

How about placing the link to the manual file on here so others can access it easily.

Belt removal requires loosening the tensioner. If you have the spring tensioner on the RHS of the engine, you can place a 1/2" socket handle in it & rotate it to take the tension off. Then just take the belt off the alternator pulley. Make sure you inspect the belt looking for cracks.
You probably have the vac pump on the back of the alt. Unless you are having problems with the brake peddle requiring a lot of pressure to stop the car it should be ok. A conventional automotive vac gauge should work. I have never used one though. With a vac line off, putting ones finger over & feeling the vac is all I have used.

Haha. Well I did NOT remove the sensor. I unpluged of course ;) Lost some power tho.

OK. Ill try to get that specific socket for the injector. Hard to find I guess.

OK. The plate between the ERG and the "elbow/knee" extension that connects to the inlet manifold (Ive read about that online). LOL I did it all wrong ;)

Thanx for the instruction about the belt!!

The vacuum lilne you are talking about is giving a constant vacuum. I have already tried that.

/ Irie

Did the sensor unplug reduce the smoke?

YES. I Think the excessive smoke is "gone" and no more soot around the exhaust. The engine runs pretty good but I lost some Power. Tried to lissen to the injectors with a stethoscope. Heard the same sound from all injectors with the sensor cable connected and disconnected.

Need a new No 1 injector ??

Just get the test done with it disconnected & after reconnect it. It is clear that your jeep wont pass in standard conditions. You are just doing a VW type thing. There is nothing wrong with it. Some one may have adjusted the injection pump to get a bit more out of it. Unplugging the sensor just restricts the amount of fuel when you put your foot down.

Yes. I gonna try that.

Sometimes I wonder if they measured it the wrong way (?)

Damn. Found some soot around the exhaust when I drove back from work yesterady ;(

BTW. 2/ Failed EGR. If you remove the AGR & are able to blow air through from the inlet (pipe) side it is failed. Simple fix is to put a blank plate ( piece of tin can) between it & the inlet manifold. The valve is NOT 100% air tight

Thanx anyway. Ill get back to you all later

Another thought...I bought one of these ODB readers that works pretty OK. I noticed that it (ODB reader and APP) does not read the coolant temperature accurate. It seems to be stuck at - 20 deg C. The gauge in the car seems to working fine tho. In the Haynes manual (petrol) there is, of course, a relationship between that sensor and the cars computer.

What if the computer thinks its still -20 deg when its like +20 as it is today. Well in cold weather the Jeep need more diesel.

I also noticed that the ODB kit gets information from the MAF sensor (It varies with RPM). We discussed the MAF earlier...

I founs this in the manual i just got - The actual time that the fuel is delivered is veryimportant to the diesel combustion process. The MSAmonitors outputs from the engine speed sensor (flywheelposition in degrees), and the fuel injector sensor (mechanical movement within the #1 cylinder fuel injector). Outputs from the Accelerator Pedal Position sensor, engine speed sensor (engine rpm) and engine coolant temperature sensor are also used. The MSA will then compare its set values to these outputs to electrically adjust the amount of fuel timing(amount of advance) within the injection pump.

Any thoughts on that my friends

OBD is useless, the system needs DBR 11 or 111, too expensive to buy. As its a old diesel you will see soot on the inside of exhaust. I think you are over ding your interpretation of everything.

Haha ok sir. Im overdoing almost everything in real life also. Well thats how you learn stuff.

OBD reader on my diesel doesn't do anything . I could still get some basic info from the ECU by sending string commands trough the laptop to the reader and got back as far as I remeber voltage only .

Ok. Found some new issues with my JEEP

1. Looked into some more about the coolant sensor. It is actually pretty important. So I took it off and found that it is a aftermarket one, with 3-pins instead of 2 (eeeh). I did some test on it and it seems to be broken. The cables seems to be ok (continuoty test).

[IMG]http://i.imgur.com/wQAo16m.jpg[/IMG]

2. Good or bad injectors ?? They all sound alike.... Maybe they still are gunked up (??) I have to check them all I guess when I get the tools BUT when I was looking at the No 4 injector I found this... But, but... the fuel drain tube is not here. Someone put a plug in it. Why do you want to do that?? Is this some kind of "MacGyver" fix when the injector or the pump is bad??

How do I fix AND where is the "tee banjo fitting" - This fuel
drains into the fuel drain tubes (Fig. 7) and back to
the tee banjo fitting, which is connected to the same
line as the overflow valve, which allows a variable
quantity to return to the fuel tank.

[IMG]http://i.imgur.com/9zKpTMV.jpg?1[/IMG]

The saga continues...

The temp sensor is a simple thermistor type. The later ones have 2. One in each of head 2 &3. Both of mine have failed & I have replaced the thermistors ~ had to open up the sensor to get at it, replaced the thermistor, a couple of $ at an electronic parts shop, & glued them back together with epoxy resin. If the 3 pronged one has 2 of the prongs showing the right resistance you can use it. If the temp gauge was working, the sensor was fine. Stop trying to fix what isnt broken.

That plug on the #4 injector return line is standard Bosch equipment. The return is via #1 where there is a hose back to the return valve on the back of the IP. This is the same on most Bosch systems including Mercedes Benz diesels of that type.

If you pull the injectors out, how will you tell if they are faulty? You cant by looking at them. Do not try & dismantle them once you have them out or they will become faulty.
You can get them tested by a diesel injector specialist.
Just remember the engine is not euro 5 or 6 when it comes to emissions. One expects some smoke.
Best you stop playing around with things you dont understand. Just get it tested without #1 injector sensor connected & then start your playing if you must. If you keep going down your current path you will end up with a shed full of bits & a jeep that wont go. Your approach sounds like a teenager with a toy that he is trying to work out how it works.

Take it easy Layback . People ask questions and try to learn . We where probably the same . If people don't tinker with cars they never learn the inside out of it and finish up paying mega dollars to garages for minor thinks .
There is no "T" banjo fitting . It is just an "end of line cap" . Mine is exactly the same as yours .
The temperature sender on mine has the 3 pin plug and socket .It is a diferential sensor with 2 (resistors+thermistor) in series . It has +5v,Signal,Ground connection .
Not sure about the 2 pin setup .It could be just a thermistor . If you measure it with multimeter on Ohms range should get a reading. If you do get a reading
than it could be ok but the dashboard connector could be playing up .
Try to find out what sort of reading a new sensor should have and that would tell you if sensor ok. If temp. gauge needle jumps up/down than more likely is dashboard connection issue .
Injectors....you can pull them out but i don't think you will see anything interesting . Has to be done by injector specialist people .There is no way that you can see the spray pattern or injector wear .Definetly leave it to the right people .

oooh sry. Just trying to learn some stuff here. How can I learn if I dont ask questions (??)

Go ahead & ask questions, I dont mind. My aim at the moment is to get your jeep on the road. Once you have it all approved, you can play with it all you like. There is a bit of information about the thermo sensor in the XJ parts Sticky.

OK it actually passed emissions test with the #1 injector cable disconnected ;) Now I have 14 month to fix the problem, step by step. NOx was 1.1. Upper limit is 3. Thanx for all your help so far.

Good to hear that you manage to pass it . By removing the number 1 injector sensor the engine drops in to limp mode and ECU will reduce the fuel amount to protect the engine . Less fuel = less power = less Nox . It is limited to arround 2000 rpm as far as I know .

The limp mode cuts in at about 2100 RPM. Up to that RPM you can get full fuel & boost. It cuts the max fuel back. You can still rev over 2100 rpm, it is just slower to build revs.


If the OP makes contact with the FB group for VM 425 engines, they can probably help him a lot as they are local to him.