Exasperated KJ Owner! Requires brain transplant or sledge hammer!

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Corky KJ

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OK what codes are displayed last when you do the key trick?
Give us the last 3 in sequence.
Create a new error....pull out the relay for the viscous heater and turn over the engine and replace the relay.
This new code is a "bookmark" so any new code that comes up should hopefully display after your bookmark.

Ideally you need the Dealers to erase all codes so you start with a clean slate although I have survived for nearly 18 years now without any help from the Dealers.;)

What pin or wire color on the Crank Sensor melted to engine? May have caused damage elsewhere.:confused:

Ok the last 3 are as follows

0340
0579
0836 crank sensor

Looking at the melted wire, looks like the white one.

Thanks again
 

turblediesel

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So if I was to fit an electric pump, would I need to by pass the mechanical? I ask this because of the pressure sensor at the back of the mech pump and also the fact that or question really, is this pump lubricated by the fuel running through? As its driven by the timing belt, you can understand why I ask? Thanks again, all this help is amazing.
The belt driven mechanical fuel pump stays as it is. They're not usually a source of problems. The in-tank electric pump just gets the fuel through the filter and to the mechanical pump pressurising the fuel line connectors and keeping air out. It was left out as a cost cutting measure. The relay and some of the wiring already exist. They figured the draw pressure of the mechanical pump was enough to do the job but didn't consider the design of the connectors.
 

Corky KJ

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The belt driven mechanical fuel pump stays as it is. They're not usually a source of problems. The in-tank electric pump just gets the fuel through the filter and to the mechanical pump pressurising the fuel line connectors and keeping air out. It was left out as a cost cutting measure. The relay and some of the wiring already exist. They figured the draw pressure of the mechanical pump was enough to do the job but didn't consider the design of the connectors.

Ahh ok. I have somewhere, an electric HP pump that I assume, I could put in line as close to the tank as poss? I also have a pipe connecting tool that I could easily place high pressure connectors on the fuel line itself? I would also then, consider replacing all the pipework from front to back. Not sure if I've said, (without trolling through my post again), that I have put two in line none return valves between the mech pump and filter and the 'in hose' of the fuel line before the filter. Would this not stop it? I know it sounds daft after such a brilliant explanation from your goodself. I assume it drags air in 'at source' then? I.E at the tank end itself, therefore rendering the said valves useless.
 

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Ok the last 3 are as follows

0340
0579
0836 crank sensor

Looking at the melted wire, looks like the white one.

Thanks again

Actually:
0340 Crank Sensor/Cam Sensor
0579 Speed control switches
0836 Transfer case.

I presume that 0836 was the last code displayed?

These codes from the file 02kjed.pdf 1,137kb in "2.5_2.8 export diesel" at:

www.colorado4wheel.com/manuals/Jeep/KJ/

The 0340 code was probably caused by the crank sensor melting a wire to the manifold so it may no longer be relevant.

I will look into the wiring diagrams for the melted crank sensor wire, the other codes you can go to the manual as above and go through the check procedures ie. measure voltages and continuity...ignore the reference to the DBIII reader because only the Dealers have such a thing!


OK firstly is your Jeep a manual gearbox or auto box?

Some differences in the wiring diagrams!

Wiring diagrams show wires as:

Sensor pin #1 Grey/ Black stripe
Pin #2 Light Blue/ Black Stripe
Pin #3 Black/ Orange Stripe

Do not see any White wire here!

Where is this "crank sensor" of yours located on the engine?
You sure you are not looking at some other sensor?
 
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Corky KJ

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Actually:
0340 Crank Sensor/Cam Sensor
0579 Speed control switches
0836 Transfer case.

I presume that 0836 was the last code displayed?

These codes from the file 02kjed.pdf 1,137kb in "2.5_2.8 export diesel" at:

www.colorado4wheel.com/manuals/Jeep/KJ/

The 0340 code was probably caused by the crank sensor melting a wire to the manifold so it may no longer be relevant.

I will look into the wiring diagrams for the melted crank sensor wire, the other codes you can go to the manual as above and go through the check procedures ie. measure voltages and continuity...ignore the reference to the DBIII reader because only the Dealers have such a thing!


OK firstly is your Jeep a manual gearbox or auto box?

Some differences in the wiring diagrams!

Wiring diagrams show wires as:

Sensor pin #1 Grey/ Black stripe
Pin #2 Light Blue/ Black Stripe
Pin #3 Black/ Orange Stripe

Do not see any White wire here!

Where is this "crank sensor" of yours located on the engine?
You sure you are not looking at some other sensor?


Its an Auto box and definitely a white wire off the sensor.

A few weeks back, the speed sensor on the back axle went haywire so yes, that 0579 code could be an old fault popping up. All OK on that front now though.

The crank sensor is behind the exhaust manifold connection on the right hand side looking from rear to front. I.E driver side UK.
 

Billwill

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Ok so the 0340 code calls out both the Crank Sensor and the Camshaft sensor...hope the Cam sensor is OK!

You need to look at the "2.5_2.8 export diesel" section from the download at:

www.colorado4wheel.com/manuals/Jeep/KJ/

Find the section that gives all of the codes....go to the advice on what to do as regards the 0340 code.

They will tell you to disconnect wires and measure from certain wires to +12 volts, measure through to ground etc. Do all you can do with a digital multimeter.

Best is to tape small needles or pins to the ends of the meter leads so that you can piece insulation if needed to make measurements....the holes in the insulation can be sealed up later with glue or melted closed. To measure the pins on the C1 connector on the ECM you will need a small needle end as the female contacts are extremely small.

You can remove the ECM C1 connector...top of the ECM..without disconnecting the battery. You are sometimes required to make some measurement on the connector with the connector disconnected and while ignition is ON.

Make sure you do not touch the meter ends with bare hands while measuring as your internal resistance screws up the meter readings.

So you follow the instructions on what to measure. At the same time go to Section 8W of the 2003 Jeep KJ Service Manual for the Wiring Diagram.

The Index Section gives you a Component location menu so you can type in Crank Sensor and it directs you to the relevant Wiring Diagram...make sure you are looking at the diagram for Diesel, Automatic.

At the end of the Menu section is a connector pinout that will for instance show you how to read the pins on the C1 connector on the ECM. On the ECM C1 connector check the wiring colors at the rear of the plug to confirm you are looking at the correct wire.

You remove the C1 connector by pulling up a tab at the top of the connector...the connector then slides outwards.

The instructions for the 0340 code also tells you to check for firm/clean cogs on the crankshaft and the camshaft when the sensors are removed. They also tell you check for a tight Cam Belt:eek:
Not sure how your problem when hot could be related to the timing belt but they are not referring to a fails-when-hot issue.

The fact that the Jeep fails to start when hot generally points to the Cam or Crank sensor...not really wiring!

You may have to take the Wiring Diagrams and the Code descriptions to an Auto Electrician to do the tracing of the wires.:(

So for example print out Page 8W-30-28....Fuel/Ignition System Diesel A/T

Pull off connector C1 on the ECM....leave battery connected.
The wiring diagram has a small error...not unusual!

The Crankshaft Position Sensor Signal 1 is Pin 1, Signal 2 is Pin 2 and Sensor Shield is Pin 3. Physically trace these three wires from the sensor to the C1 plug looking for any scraping of insulation to chassis/engine and measure for continuity from end to end.

Do the same as above for the Camshaft sensor.

There have been some owners who have measured the Cam and Crank sensors when removed. At room temperature you get certain resistance...heat sensor up with a Hair Dryer and a faulty sensor gives you different readings!

Have fun!;)
 
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Corky KJ

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Wow, is this homework to bring me up to dateo_O Mind has gone wonky already ha ha. Will do, suffice to say I change cam sensor at the same time as crank as I got a good discount for the two (both original parts) so I would assume the cam sensor to be ok. To say also, the bloody thing wont start at all now even from cold as before. It will with the easy start but alas no longer on it's own back as before. So that's both hot and cold non starting now. I actually take this as a good thing as it may give some proper indications now. I just find it so strange that taking the fuel pump regulator off and putting it back on after a we spray with brake cleaner, she starts straight away after two cranks. Stop and start a couple of times leave it and ......you've guessed it.....non start again.
I will do the deed on the electrickery stuff on the morrow, as you can tell by the time, have been on lates...hate them...I will keep you posted. Give me a day or two as it looks like I'm gonna have to get my old grey matters cobwebs off
 

Corky KJ

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Ok chaps, at last I have had chance to have a good poke around and get the tests you have suggested sorted. Every sensor I could find was removed, wires traced etc etc. took forever!

Thankfully my dad is an electrician come electronics wizard of some years now and knew the craic straight away from reading your thread. Top and bottom is, is that all readings were fine! We warmed up the crank sensor with a hair dryer and it stayed put.

So, in his humble opinion and after completely baffling me with science UTTERLY! He thinks it may be the simple fact of drawing air in somewhere. I, for some reason, cannot see it being the injectors, so would fitting the 'in tank' pump be worth the while? I can get a decent second hand one for peanuts off a right off I know about. Its quite a young car with low miles.

I also believe the seals are not perfect at the tank end, could that also be an issue?

Im picking at straws now completely.
 

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Seeing as your Jeep is now not starting even when cold and no codes are present could point to a fuel supply problem....most fuel problems such as a clogged fuel filter do not post CEL codes!

Our early Export CRDs have always seemed to not have the problem of drawing in air to the fuel lines at the tank fittings compared to the 2005/6 USA CRDs. There used to be a member here and on LOST called TonyCRD who really was an expert on his 2002 Export 2.5 CRD. He initially thought that our Export models had a built in fuel pump in the tank which prevented air being drawn into the fuel lines at the tank.
Further examination by Tony found that our Jeeps did not have an internal fuel pump....just seemed we had better fuel connectors at the tank on our Export models but maybe they are getting too old now.

A lot of CRD owners have fitted in-tank pumps or external pumps and have replaced the tank fittings to prevent air in fuel problems.

If you trace where the fuel line from the tank to the filter and the return line you will see they come to a crosspiece near the fuel filter. I found a fuel leak at that connector by feeling around there so made those connections nice and tight and also checked for leaks around the fuel filter. I definitely was getting air into the system as I had to repeatedly pump the plunger on the top of the Raycor fuel head until it got firm. The maintenance manual tell you to unscrew the nylon plunger, lift it up and pump it several times until the plunger gets firm. I found that it helped to pump like crazy and as it got hard I would crack open the Brass nut next to the plunger to let fuel and air out. I have not had fuel problems for along time now!

So I would advise you to make sure you have a clean fuel filter.
Check for leaks around the filter head and the supply pipes.
Check for leaks at the fuel tank fittings.
Pump out air at the fuel filter head.
Look into fitting an in-tank or external pump.....most of the wiring is already in place!

Our early KJs are neat in that we do not have to drop the fuel tank to work on it....remove the pop-rivets holding the carpet in place in the rear load area and get access to the cover on the top of the fuel tank!;)
 

Corky KJ

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Thank Billwill,

Yes, I have an in line high pressure FP in my garage ……. somewhere....which is brand new bought about a year ago for another, dare I say it, 'project'. Its all I can think of now. I have a tool that I can make up fuel pipes with pressure fittings rather than screw clips and have a few meters of high pressure plastic fuel pipe. I may just change the lot while Im at it.

I have had a look in the boot area under the carpet, and although there isn't a removable 'hatch' as such, you can see where it should be. I may just cut it out and make the cover myself, it looks simple enough.

That said, to remove the tank doesn't look that hard either so weather depending I think will decide the route I take. (Its been bloody freezing over here, even though the thermos state 8deg centigrade it feel more like minus 8 in the howling wind!).

I am thinking also of completely bypassing the filter set up as is to eradicate any issues there whilst testing. I think I said, someone put in a retrofit replacement in as in standard 'Ford' type in and out with long filter and plunger. To be fair, this has been fine, no leaks, seals spot on so although not sure if it would make a difference, I am going to try the pump first. Thankfully I can get a full Jeep filter housing etc from a friend who has a right off with only 65000 miles on the clock, unfortunately the bugger has taken the tank and in tank pump off and sold it! Swine he is lol.

Thanks again, and I will keep you updated. I have learned so much on here for hich I thank you. Its saved me a fortune.

All the best
Chris
 

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I am a bit confused as to what mechanical "fuel pump" you are using.

The CRD comes out with a CP3 pump driven by the belt and is a very high pressure unit. It has a regulator mounted on it.
This is a very reliable component...I have never heard of anybody replacing it and it is responsible for supplying diesel to the fuel rail and hence to the Injectors. The fuel rail has a pressure sensor on it and a solenoid to control the fuel flow. It basically has three separate chambers in it hence the CP3 name. You must be very careful when working with the output from this pump...the high pressure can cut a finger off! When checking for fuel leaks from this pump follow the details in the Service manual...you have to use sections of cardboard to trace any leaks as the spray is invisible to the naked eye. Any problem with the pressure at the fuel rail will post a CEL!

Do you still have this unit installed in its original form?
There is no way you could replace this with any other pump.

The supply of diesel to this pump is basically supplied to it via the fuel filter head, Raycor, under suction normally. Some owners have added another electric pump to pump fuel from the fuel tank to the CP3 pump...this can be in-tank or external....I hope this is the pump that you intend fitting.

I am surprised that your Export 2003 CRD does not have a removable cover on top of the fuel tank....I wonder if someone replaced the fuel tank but maybe yours is a late 2003 model hence the one-bolt MAP sensor and maybe at that stage the closed fuel tank came into use also.

You ideally need to have all your CEL codes erased so that you know what error you are chasing now....fuel errors....other than Fuel Rail errors may not cause codes but any new error logged should be chased up!
 
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Corky KJ

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Yes It's an electrical in line hi pressure pump not mechanical. The mechanical one has had the pressure sensor replaced when I did the cam belt ( took it all off at once) again genuine part.

The filter head is a bit strange as it looks like it has been taken straight of a Ford. I.e its deffinately not a jeep part. I will get the one off my mates though whilst doing the rest of it.

The fuel rail pressure switch has also been replaced, genuine part, that said, it is interesting to note you say there is a solenoid on the fuel rail. Is this electrical too? I say this as the only electrical connection on my rail is the pressure switch. At the far end near the bulk head is what looks like a blinking plug. Is this what you mean? There is nowhere for a connection though, just a large but like plug. I haven't had this off yet mind as I thought it was just a blank in bolt.

As you say, once running and I nip off the supply line to the rail, the spray is phenomenal so I know there is some hell of a pressure there. Just seem weird that as soon as I stop the engine no matter if I count to one or a hundred, it wont start for no one.

Unfortunately the Jeep dealer near me went bankrupt last year and the nearest is 80 miles away. So a bit of a long way to go to clear codes. No one around here wants to touch it! Ha ha ha

I have done as you said though and created a bookmark on the list and so far except for the Map sensor, it's not posted any since. I replaced this th other day and cleared the managememt light with my coder.

Hope all this makes sense to you.
Thanks again
Chris
 

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Ok there is no solenoid on the fuel rail for the diesel....the pressure sensor switch is at right angle to the rail facing the left side of the engine bay...this is the sensor I presume you have replaced.

The fuel pressure regulation is done at the rear of the CP3 pump.

Have a look at the manuals for the 2.5 L CRD in the section "2.5_2.8 export crd" in the link to the manuals I gave you.... Section 14 gives a good description of how the fuel system works and how to check for leaks. This description is pretty valid for the 2003 2.8 Export CRD that you have. Whenever they refer to the "in tank fuel pump" they are talking rubbish. Most of the cabling for this pump is in place and Jeep obviously were planning to fit one but decided to save money and left it out!

Once you have re-fitted the Raycor fuel filter head, primed it and checked for fuel leaks, fitted electrical low pressure fuel supply pump, things may work nicely with a bit of luck.
 

Corky KJ

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OK it looks like a hallelujah moment here...

I replaced the wee pressure solenoid at the end of the rail near the firewall cylinder 4. No more pressured leak off from the tell tail drain. So that was that out the way. Although she still wouldnt start, once fired up, seemed to run much quieter than ever.

Emptied the fuel filter re did all the joints replacing seals as required. (Second time have done this but thought sod it, start again, cant do any harm).

Took off the fuel pump solenoid at the back of the pump, cleaned put new seals on. And bugger me, it fired up after litteraly a second of cranking. So turned off after leaving ticking for 15 mins, tried again and bugger all. This lead me to then suspect the solenoid was up the creak, despite being brand new Bosch as original.

Farted about a bit, swore a lot because now, even with easy start, she wouldnt go. Bled it like a mad man from every conceivable bleedable bit.

I then, by accident, dropped a spanner down the back of the pump, when retrieving I caught the wire on the pump solenoid. Again F'd and Jeff'd a lot, scrapped knuckles...you know the score. Well after checking the connection, I tried again...brooom away she went. Took for a 29 mile run, came back left for 5 came out ...brooom, away she went and has been fine the rest of the day. Just been to recheck the connection and have noticed a wire hanging on by a thread at the plug end where it joins the spade end for want of a better description. So scrappers tomorrow, snip a plug off with plenty of wire and solder together.

Alm I can say is you have been a star and I have learned so much from your advice and through that advice got there in the end without emptying my wallet too much.

Thank you for you kind help.

Very best
Chris
 

Corky KJ

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PS, the pressure relief valve looks like a blanking plug. Does not have any electrical connections at all.

Swine to get off as tight as hell. Had to remove the rail to get at it and remove. This is in a wee chamber of it's own so to speak. Previously the wee tell tale was blasting out diesel almost at full pressure. In turn this kept blowing the return pipe off. God knows why I hadn't noticed it before. So on changing the part, this has had some effect. It has stopped the sudden pressure drop from the rail. I think the connection as mentioned has just been maybe a fluke find as once running it was fine. If you unplug this thing, engine stops altogether and wont go. So looks like a good combo of things....

Good thing is, I know for sure all the sensors are A1 and brand new. So shouldn't have any further issues on that front.
Cheers
Theres a pint in the post lol
Chris
 

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Great hope it works well forever!:)

The sensor on the fuel rail can be replaced as you have just done but cannot be removed and re-fitted!

There are no gaskets used...the new sensor is designed to cut into the aluminum fuel rail when tightened. So it can only be fitted once...remove it and you need to buy a new one!:(
 

Corky KJ

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O bugger!! Lol. I'll leave alone then.....

Sorted the plug. All done and so far so good. Started like a dream this AM despite a howling wind chill of minus 5 rattling through the grill. Once new plug fitted, again, starts every time after a couple of cranks.

For 300 pounds I got a dog that had been butchered, but its unusually solid underneath and around the normal corrosion spots. I've spent about the same on it in bits and Bob's, time is free and do it as a hobby (ish) any way.

Just Selena similar with 12 months test o it same age and miles going for 1400 pounds, so even if I got a grand for it I would be smiling.

You've been a massive help and very patient for which I thank you.

All lmao the very best from SUNNY and HOT...NOT...Scotland...
 

Corky KJ

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Ach well, back to square 1! Fired up fine this AM and back to its usual self when hot....I GIVE UP :confused::confused::mad::mad:

I cannot for the life of me think of anything else to check. All I can now think of is around the throttle area. Each time I switch off, there is a loud click from over the turbo side. Yet to find what it is.

O the Joy's........what amazes me more is this morning it was colder than it has been for a long time, deep frost etc. Started after two clicks of the glow plugs on first turn of the key, it's never started that quick!...

There is deffinately no air in the system that's a certain! Pressure on the rail is right up there. So just wondering now if the pump itself is goosed but cant really see how as it is a new one and fitting it made no odds to the issue anyway.

Any more ideas? I:confused:
 

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