• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

VW TDI into a 99 XJ

That's only 10 degrees more canted than normal. Evidentally it's a "1g motor" as the van guys mount them directly on their side for use in the old busses and such.

If you look at the drain plug, it's roughly right where it's supposed to be. And what would normally be the leading edge has a pretty significant ramp on it to funnel the oil back.
 
Thats a frickin' TRIP to see that much room in the engine bay... Cool project for sure... I'll be keeping tabs on this one!
 
What I meant to post earlier.


belowfromrear-1.jpg

-
motorbelowfront.jpg
 
I actually might hate you.

How easy is a 2000 TDI to cover to biodiesel or vegi oil?

It's a common theme. Generally has more to do with my personality than my toys.

The ALH motor (1998 - 2005) is one of the easier to convert. In this case the only conversion to Bio is 2 short fuel lines and a couple o-rings.

For veggie, you need only to plumb in the hardware to pump fuel from a separate source.
 
I borrowed some heavy weight scales this afternoon.

Corner weights are: 897 790
737 696
Totaling: 3120 lbs.

Pretty not bad!!

The motor/trans have been moved forward about 4 inches and the front prop shaft isn't currently installed. But otherwise the thing is roughly stock ('99, 5 speed, "Classic"), factory spare tire and I suspect it had VERY little fuel in it. I am confident that when I am done and the motor is in the other body it will gain a fair bit of weight. At least a couple hundred lbs (plus my fat ass). But damn if this thing isn't respectably light!
 
Have fun getting the XJ gauge cluster working with the VW stuff. IIRC the XJ cluster in the 97+ are almost completely controlled by the CCD bus. and requires the XJ ECM to drive it. You will probably be better off by just building your own gauge cluster with aftermarket gauges.
 
Last edited:
Have fun getting the XJ gauge cluster working with the VW stuff. IIRC the XJ cluster in the 97+ are almost completely controlled by the CCD bus. and requires the XJ ECM to drive it. You will probably be better off by just building your own gauge cluster with aftermarket gauges.

100% correct here.

It is possible but it will not be easy.
 
Have fun getting the XJ gauge cluster working with the VW stuff. IIRC the XJ cluster in the 97+ are almost completely controlled by the CCD bus. and requires the XJ ECM to drive it. You will probably be better off by just building your own gauge cluster with aftermarket gauges.

I'd like to avoid building a new cluster, but I am not opposed to it. My plan is to leave the Jeep ECM in tact and double up on as many of the existing senders as I can. For example there will be 2 oil pressure senders, 2 temp senders etc. One set for the VW and one set for the Jeep. In theory this should control everything as even if you motor is keyed on and not running the sensors respond. Which is basically what the truck will see. The speedo SHOULD work on it's own. It's really just the tach that will likely prove to be an issue.

If I go straight aftermarket it's dramatically less an issue.
 
That's a stock AX15 bellhousing you said, right? And a stock XJ flywheel?

You should be able to bolt the Jeep CPS right into the usual location and connect it to the XJ ECM.

The only issue I can see is that the Jeep is going to be setting a CEL no matter what you do. So what I would do is open the Jeep cluster up, disconnect the bulb for the CEL from the wiring built into the cluster, then feed it with a wire from the VW ECM or VW cluster module (gutted down to the bare minimum, since you won't be using any of its other functionality) CEL driver.
 
Just in the event that anyone is wondering..

The Cherokee (with the TDI) weighs in at 3127 lbs. My 99 Cherokee with the 4.0 and a 5 speed - 3317lbs. Both trucks were very low on fuel.

And the 10,000 question to make this comparison worth anything. My 02 Jetta with a 5 speed and pretty much every option I know of and exactly 3/4 tank of fuel. 3015 lbs.

So to those wondering about weight.. There is roughly a 100 lb difference between the 2. I am more than a little surprised!
 
That's a stock AX15 bellhousing you said, right? And a stock XJ flywheel?

You should be able to bolt the Jeep CPS right into the usual location and connect it to the XJ ECM.

The only issue I can see is that the Jeep is going to be setting a CEL no matter what you do. So what I would do is open the Jeep cluster up, disconnect the bulb for the CEL from the wiring built into the cluster, then feed it with a wire from the VW ECM or VW cluster module (gutted down to the bare minimum, since you won't be using any of its other functionality) CEL driver.

I am pretty certain it's a stock AX15 bell, yes. I am moderately confident it's out of a 97.

The flywheel however is from a Volkswagen. Though I may look a little closer as to how the CPS actually works, perhaps I can use the Jeep sensor and modify the flywheel..

I had thought about that for the cluster too. I may go that route. Though I may use a couple idiot lights also. There are lights for the Cruise (if/when), glow plugs, possibly some other stuff. At least the glow plugs..
 
This is cool!

And you're right about the weight...VW TDI's weigh a lot more than most people would think they do.
 
I am pretty certain it's a stock AX15 bell, yes. I am moderately confident it's out of a 97.

The flywheel however is from a Volkswagen. Though I may look a little closer as to how the CPS actually works, perhaps I can use the Jeep sensor and modify the flywheel..

I had thought about that for the cluster too. I may go that route. Though I may use a couple idiot lights also. There are lights for the Cruise (if/when), glow plugs, possibly some other stuff. At least the glow plugs..
Interesting.

If you want to make the Jeep CPS work on the VW flywheel, what you really need to do is duplicate the flywheel edge to CPS nose air gap (mostly to make sure you even get a signal, and also don't shred the end of the sensor the first time you turn it over...) and the notch pattern on the edge of the flywheel. If you need something to measure the flywheel notch pattern off of, I have a few old flexplates out of XJs, you can have one free if you pick it up or are within reasonable distance. Obviously you only need to duplicate the pattern, no need to keep it timed right with regard to cyl #1 or anything since the ECU won't be firing any spark plugs or injectors anyways.
 
The Heeps flywheel has three groups of four notches spaced 120 degrees that the CPS reads for position and to generate the rpm signal to the PCM.

You would need to measure the gaps to get it right.

All things considered, it would IMO be much easier to just build a new cluster. Why fight it?
 
Interesting.

If you want to make the Jeep CPS work on the VW flywheel, what you really need to do is duplicate the flywheel edge to CPS nose air gap (mostly to make sure you even get a signal, and also don't shred the end of the sensor the first time you turn it over...) and the notch pattern on the edge of the flywheel. If you need something to measure the flywheel notch pattern off of, I have a few old flexplates out of XJs, you can have one free if you pick it up or are within reasonable distance. Obviously you only need to duplicate the pattern, no need to keep it timed right with regard to cyl #1 or anything since the ECU won't be firing any spark plugs or injectors anyways.


I just realized where you are. I'm in Templeton. Maybe an hour and a half from you. I may make the pilgrimage down and snag one of those from you. There is a chance I can simply adapt the Jeep flywheel to work too.

Definitely appreciate the offer!
 
Goddamn, that's not far at all! I almost bought a house up there actually, on School House Rd.
 
Back
Top