Morat

Sadly the front end was just as bad. The ECU would work/not work if you tapped it with a screwdriver and the old injectors were toast. There were loads of air leaks and it was basically held together by luck. I bit the bullet, and there's a full new LPG system on the front. This means that there's pretty much nothing left of the old system apart from those tubes where the LPG is squirted into the manifold.
Moving the reducer to the left of the photo has shortened the runs for the coolant pipes. Sadly the new ECU is still in the same place so I don't think I'll be able to get rid of the cone filter and replace it with a stock airbox just yet.

Here's the view - just in case you're wondering what the hell I'm talking about! It does seem like a lot of bother, but this sort of investment pays back in about 8000miles with our stupid petrol prices and the fuel "ahem" economy of the 4.0

Morat

What was the damage I hear you ask?
£2100

Say it fast, it doesn't sound too bad!
So, that's the end of my dreams of a Tru-Traks front and rear and an OME lift. I'm going to be working for my Jeep for the next 16 months! Let's see if I can get the credit card paid off in time - and if I do I'll probably be back for more I'll post up a final account when I've done a couple more small jobs.

Morat

Changed the front rollbar bushes today. I sprayed the bolts with WD40 a few times this week and got underneath with a 15mm socket and ratchet. 30s later I was heading into town to buy a breaker bar which did the trick. Ahh well, you can't have too many tools :-)

The good news is that the Kerlonk coming underneath the front left has stopped completely. This jeep is really starting to sound civilised!

Morat

And some vacuum hose finally turned up. For anyone not familiar with the pecking order of courier companies in the UK it goes a bit like this.

1. Courier companies
2. Some bloke with a car
3. Some bloke on foot
4. Some bloke on one foot
5. Earthworms
6. Yodel

Anyway I found a spare vacuum connection and hooked up the line for the heater controls and the cruise control.

Next up, professional re-gas because I want to be sure the new compressor is getting a good diet of nice clean gas and oil.

Then it's going to be time to look at the exhaust system properly. The cat is rattling a bit (much easier to hear now the rest of the jeep is quiet) and there is a pretty good tick from the front which sounds like an exhaust manifold like to me.

Morat

Just when I was getting smug - crank crank sputter crank. With the sound of a dying cow coming from the fuel tank area. Yep, the fuel pump is toast. Brand new, about 500 miles on it. Must have been an airtex after all - well I'll know more when I rip it out. I've ordered a new Denso (pump and fittings only) from the USA for about the same as the full module cost from ebay.co.uk. Hopefully a Denso pump will last longer than whatever was in there before.

I'm now officially glad that there's a hole in the boot floor so I can get onto this job without dropping the tank. At this rate I may as well swap the pop rivets for a hinge and lock :/

Morat

So, Fedex got the new pump all the way from California to Yorkshire before losing it about 20 miles from where I live. Seriously. So that was a wasted week.
Then I bought a Bosch locally and fitted it into the existing module. Then I thought that I'd better change the fuel strainers on before re-fitting. Are there any available in the UK? NO. of course not. FFS.
So RockAuto send me the parts for about 10 quid and Fedex charged me 24 for the shipping. This time the box arrived on time, with the right bits and everything fitted just fine. BTW, if you end up fitting a new pump to an Airtex fuel module, you need FS220 and FS221 to replace the sock and internal strainer.

SWEET! it fired up first touch and ran fine while I tightened up the battery clamps and fiddled with it for a few minutes before I took it for a victory lap. I got 100 yards up the hill running on Petrol and it just cut out like I'd killed the ignition.
I went to restart and MOOOOooooooOOOOO from the back. My perfect, near silent, Bosch fuel pump had failed just like the cheapo Yuzhou, Made in China pump.

Once I'd recovered my heap, I had a chat with Bob the Spanner God. He said it sounds like the pump might be running backwards. HUH? How can that be?
Well, he is 70 years old and has worked on everything made since about 1920 so I grabbed a spare battery, some wire and looked up the diagram on the FSM. If I'm reading it right, it's Green/White for positive and Black for ground.

Here's what happened:

First run is correct polarity, second is reversed. Looks like Bob was right.... and I've no idea what sort of fault could make a pump run backwards but I'm about to find out.

Basslicks

Well THAT sucks! Figure it out yet?

Morat

Turns out there was a kinked fuel line up front and he has re placed the clips which hold the top of the fuel module to the main part with nut/bolts because we couldn't be sure if the module came apart in the tank or when it was pulled out of the (off centre) hatch in the boot floor.

It works. It works!!!!! It's aliiiiiiiiive! 😊

Some people are worth their weight in gold because they just make problems go away. Bob is a legend.

Basslicks

Nice!!!

Morat

Annnnd I had some problems with an intermittent misfire and some difficulty with hot restarts. Also a slight burning smell that I wrote off as "just a burning smell".

After a few days of perfect running I'd get a small misfire. Then a maybe a large misfire. Then a few more days of perfect running.
Two codes, both for transmission.

Meh. I posted, I read the answers, I tried following the replies and found nothing.Everything just looked fine and it's freezing. I gave up and took it to the garage (an hour away but specialise in Jeep) and they found....

CPS wires melted on the exhaust. Maybe that burning smell was something after all :/ Replaced with a new CPS for piece of mind.

New back springs have arrived and should be fitted today or tomorrow. Excited!

One final little tweak, I have a power aerial on my Jeep (it being a LTD). I stupidly cleaned it without re-lubing it. The next time I tried it, the plastic broke inside so it wouldn't work at all. I HATE having the stupid aerial bobbing around in my vision when the radio is off (being RHD, it's just THERE).
I've got a replacement bit from antennax in the USA and I'm hoping that will do the job.

mnewxcv

dude this thing is cool. So you select LPG or PETROL with a switch of some sort and the computer figures it out? Can you switch on the fly while driving or have to restart? I'm fascinated.

edit:

also see you have 2 fog light switches. is one for rear since you UK guys have rear fogs? How often do you use those?

Morat

Glad you like it I'm going to pick her up after work, my wife saw my stupid grin and rolled her eyes. She knew exactly what I was going to say!

There's a switch which is a combined gas gauge and changeover switch. I don't have a photo to hand, but it's just a little switch with 5 LEDS. 4 LEDS give you the amount of LPG on board and the fifth tells you if you're running on petrol or LPG.

You normally leave it alone and the LPG computer switches to LPG when the coolant temp is high enough to keep the reducer (evaporator) from icing up. The reducer is plumbed into the engine cooling lines and heats the LPG so it changes from liquid to gas before injection into the intake manifold just upstream of the intake valves. No need for fancy spray patterns - it's already gas!

If you run out of LPG, the system swaps back to petrol so when it's all working right you've got two fuel systems and you can swap between them just by pressing the button. Modern systems are fully sequential so they actually change over one injector at a time and you can't even feel the changeover.

Of course the CPS is needed for both systems and you do actually need a working PCM because the LPG ECU only applies a delta value to the petrol injector pulses to compensate for the slightly different characteristics of LPG (higher octane, but lower calorific value). It's all worth it though, petrol is at a 5 year low near us at £1.03 a litre and LPG is at 53.9 pence per litre.

The rear foglights are great for tailgaters* And yeah, good in fog too. All vehicles have them by law in the UK and EU. Round here, we do get quite a lot of mist/fog so I use them a lot in the winter, they do give some peace of mind when you're peering out of the front so hard you're not really checking your mirrors very often.

Can't wait to see my jeep sitting up again!

*that's people who drive 3ft behind you.

Morat

New springs! Not exactly a lift but the rear is up rather than down, if you see what I mean. It's not quite as dragster as it looks in that photo but I could probably do with a half inch at the front. Or no. It rides well and it doesn't rub

The Jeep garage had her washed before I picked her up so I couldn't resist a quick photo this morning.

Also, she's running at her best yet - nice and smooth with no restart issues. I guess that CPS is quite important.

Morat

Soon after that photo above, I was stuck again. This time it turned out the be the coolant temp sensor. Before I bought a new one, I poked the old one and just looking at it and cleaning off the plug seems to have fixed it. Smooth running ever since

Actually extra smooth, because Bob the spanner God looked it over while I was scratching my head over the coolant temp sensor and spotted where I'd left the HT lead for the front cylinder rubbing against a pipe. It was shorting and I had a misfire at idle. "Don't they all sound like that?" "only if they're 5 cylinder, and this has 6". OK.. ok...

So, super smooth and I'm loving it.

Loving it so much I took it get the aircon regassed today. It was OK when the new compressor was put on but they warned me at the time that it was low and I should get it done properly with vacuum and new refrigerant. So I did and the aircon is Ice cold. Impressively cold - and no leaks reported!

Then I noticed that the LPG system was off and not just switched off (red light on) but totally dead. Odd. Just as I was wondering if I was going to have to shout at the aircon people, I thought I'd switch the aircon off and see what happened. Yup, the LPG fired up and took over again.

I haven't double checked with a multimeter yet, but it looks like the LPG system power is being taken from the same circuit as the aircon - which wasn't working when the new LPG was installed. So, the aircon kicks in and the LPG computer doesn't have enough power and goes dead. :/ Luckily the Jeep just falls back to normal fuel but it is a pricey way to run aircon.

So, it was already booked in for a scheduled LPG service. I'll be asking them to change to another 12V feed - hopefully the dash gauge isn't lying when it says that we have a good 13V. I'll check the battery voltage with the aircon running tomorrow.

two steps forward....

Morat

Finally took her offroad properly this weekend!


OK, it's a long and boring video - but I was pretty amazed by what a stock XJ can do with just some decent tyres.