Hi Guys,

So as you might have seen from a couple of other threads, I recently bought a 2004 SE7 Disco. I am in love with it, however like all Disco's it comes with a package of issues. So I brought it to the mechanic for some code reading and diagnosis (which turned out to be the same diagnosis as this forum). I need to install a new Coil and new wires and a new XYZ switch. The mechanic talked some rubbish about my Bosch +4 platinum plugs but if Disco Mike is using them I am going to stick with them as I am not too sure this mechanic isn't trying to rinse me. I know the wires are doable and have read the sticky on it, but how possible and how much would you recommend a rookie mechanic trying to fix a coil and install a new XYZ switch myself? He is trying to charge me $1300 for the parts and labour for those jobs and I think he might be a padding the bill quite considerably.

Also the truck is stick when you try and go into reverse and the brake lights are not coming on sometimes when you put it in reverse. From what I can tell on forums and from what the mechanic says this is probably the XYZ switch going, most likely from the AC dripping on it. Is this you thoughts as well?

Thanks again.

 

Truck is stick - you don't mean stick shift?

If you have an automatic tranny, XYZ is a pack on the driver's side, they are like $600. There have been posts about removing them, drilling out rivits, clean out mud, re-install. The install / remove process is well covered in the RAVE, hope you have download it, has all the factory shop manuals.

Coil and plug wires will require you remove the top of the intake.

All this is quite DIY, if you are prepared by reading about it first.

While you have intake top off, borrow a pressure test gauge and check fuel pressure on schrader valve - you can't get to it other wise. Should be 50 PSI.

 

Sorry, I meant sticking, not stick, and yes I have read up on the repairs and also have the RAVE manual saved on the desktop and have flicked through the relevant parts. I just didn't want to get into something that is way over my head.

Also could it be the brake switch instead of the XYZ which is causing it to stick before going into reverse? Essentially it is taking a couple of tries each time to get it to go into reverse from drive. Brake switch would be so much easier and cheaper.

 

Go get your codes read at a local parts store then get back to us with the 3 or 4 digit fault code numbers.
What are the main issues you are dealing with?

 

If the shifter is "sticking" going from Park into Reverse I agree that it does not sound like an XYZ problem. More likely the brake light switch, which is a $20 part vs. $600+ for a new XYZ (or $100 for a used one).

When you shift through the gears do P,R,N,D,3,2,1 appear in the LCD display on the dash to the left of the odometer? And do the the proper red lights illuminate on the shifter as you run through the gears? If so it's likely not the XYZ. My XYZ problem years ago never caused the shifter to be sticky coming out of Park; it caused me to be unable to remove the key from the ignition because the computer didn't recognize the tranny was in Park.

Have someone check your brake lights when you step on the brake pedal. If the lights don't come on, or come on irregularly you need a new brake light switch. That would also make your shifter sticky coming out of Park because the transmission shifter solenoid needs a signal from the brake light switch to release the shifter. Really, really easy to install.

Separately, Mike is right that you should let us know what codes you are getting so we (he?) can help with diagnosis. That said, the coil packs fail only rarely on DIIs so if it were me I'd start with new plugs and wires first (depending on the codes), and then see if that solves the problem. You should also test the coil packs with an ohm meter before replacing. I got mine out and back in without removing the intake but it's not easy. BE VERY CAREFUL WHEN LYING FACE DOWN ON THE TOP OF THE ENGINE NOT TO PUT WEIGHT ON THE VACUUM LINES COMING OUT THE RHS OF THE PLENUM. THE FITTINGS WILL BREAK. Trust me on this. I learned the hard way.

 

actually if you pull off the tubes to the heater core you can snake out the secondary air pipe and get the plugs out that way. not fun but it works.

and if you are really lucky you can use a seven mm socket and get out the offending coil.