I currently have some ACE problems with a project truck I bought a few months ago.

1999 Discovery II - 108,000 miles

Took it in to a shop that advertises they work on Land Rover - the said the ACE ECU was faulty and quoted me about $1,400 to fix. Right. I replaced the ACE ECU with a used unit - no joy.

Pump is working - Fluid is circulating to valve block and back - the two pipes to the pump and reservoir get warm and the fluid spins in the reservoir tank.

I figured that it would cost me about the same to replace the Filter and Transducer as it would to take it into another shop for a diagnosis.

The old filter had a little light brown rubbery substance in places - reminded me of dried rubbery silicone caulk. I cleaned out the filter area - installed new filter. Replaced the Transducer.

I just checked the valve solenoids - the two on top of the valve block click and seem to open and shut freely. The valve on the side does not click or seem to open and shut.

My thought is that this rubbery substance is probably gumming up the valve.

Has anyone had any success in rebuilding the unit? I'd like to open it up and clean it out - flush out the lines and such while the valve block is out. I understand I'll have to have the system bled and calibrated afterward.

The only other thing I haven't tried is replacing the Accelerometers.

The relay is pulled to kill the chime and lock down the system.

Any advise would be greatly appreciated.

_____________________________

replaced MAF
replaced all oxygen sensors
replaced power steering pump
replaced tensioner pulley - both idle pulleys

Need to fix front sun roof

 

That material is most likely decomposed seals.
Do you have a service engine light or ACE light on when running?
You might want to do a full 4 quart flush and see if it helps. If you want some help with this, send me your number and I'll try and help.

 

Thanks Mike.

When I bought the truck no warning lights at all - just a bad water pump.

A few months into it I had check engine codes for MAF & Oxygen sensors. Replaced. Lights out.

ACE system is not leaking anywhere.

After driving for a extended time on rough dirt road - Rampart Range Road - I'm sure you know the place - I got a yellow warning light. Parked it, next day it was fine. Three weeks it was fine. Then one day first turn I take I get the red flashing with a chime for two minutes.

Took it to the first shop for help.

I have the relay pulled anytime I have to drive it - put the relay back in and guaranteed red flashing ACE light.


Love the truck - just not familiar with the mechanics of it yet.

 

So, lets talk tomorrow.

 

Was there a solution to this problem T-rex? I get an amber ACE light after driving for awhile at highway speeds. Did the 4 quart flush and it still happened. Today I'm going to look at my filter. What did you clean it with?

 

Clean it with brake or carb cleaner. Do not let too much fluid drain from the filter hole or you will have bleeding issues.
Do you have any service engine light on, if so what are the fault code numbers?

 

Thanks Mike. I don't have any lights on or fault codes. The amber ace light only randomly comes on when driving more than 30 min or so at highway speeds it seems. I don't believe I've ever seen it when driving around town. When I turn the rover off and then start it again, the light doesn't come back on again at all or sometimes it does again after driving for awhile.

 

I've got to make an appointment to have the codes read.

Thanks to Mike I have a direction to my efforts

I'll keep the thread posted with what I eventually find.

 

It took a while but I've got it going.

Took the truck to MIT in Evergreen Colorado for diagnosis - great guys to work with! They couldn't tell me what was wrong with the truck - spent a good half hour with me and gave it their best shot. When I left there we kind of decided the next step would be to swap out the valve block.

I got a used valve block and then got busy with other things and let it sit on my work bench for a while. Over time I decided to plug the relay back in and see if anything had changed.

It still gave me the red light and chime. Let it go that way for a few days and noticed a change in when the error would happen. Some times I could drive blocks and it would be fine before going off. Then I noticed it would trip without even moving.

This made me suspect the accelerometer sensors. I tried to find a source to get a new one and struck out.

The other day I was at the junk yard to hunt down a part for my SAAB when I ran across a Disco II - No ACE installed. Drat! After finding a few more I found a truck that had the ACE installed - no pump - but it did have both accelerometers. SNAG! Cost me next to nothing too!

Got home swapped out the sensor on the underside of the truck and BINGO! Back to normal!!!!!!! Happy dance!!!!

 

The previous owner of my truck burned out the ACE pump. I finally got around to replacing it this morning with a refurbished pump. The fluid doesn't appear to be circulating. The previous pump would circulate but was definitely burned up as small little bubbles would appear in the fluid. Any suggestions as to why the pump wouldn't be circulating. I also replaced the filter when I was diagnosing the original pump. Also, does anyone have any experience rebuilding these pumps? Thanks a lot, guys.

Best