Originally Posted by suprPHREAK

Hey all, thought I would share my predicament for you (been a bad car year for me...sigh).

Anyway, this passed May long weekend, I was driving along and then got the dreaded "service required" screen:

There are only 3 times this will show up: doing donuts in the winter without first turning off the ASC (reboot the car, goes away), when you put a donut spare tire (wheel rotation out of spec, just put a proper diameter tire on), and when your ACD/AYC pump fails.

Of course, mine is the last one. But it wasn't as direct as you might think to sort this out, and so I share my experience now, so that other Toronto enthusiasts may be spared the mild aggravation.

First and foremost: this pump is covered under the 60,000km warranty. Mine failed at 102,000km. FML. Second, Dealer retail price for this is $1600.

So after getting the message, and doing what the owner's manual said to do (stop, restart motor, see if it goes away), it did go away, and for a few days. Then it came back, and would not go away. So I went to the dealer to check it out. As it turns out, mechanics don't actually do mechanical stuff anymore, they are IT guys in coveralls. He plugged in the MUTIII, and ran diagnostics, but got stuck at the Actuator Test, so he could not confirm that the pump was running. He did notice that the ECU version was out of date, so he reflashed, and the error disappeared! WAHOO! There is monies in my pocket!

But I noticed a new symptom: whenever I drove, the ACD mode would blink (the little Tarmac/Gravel/Snow display). It did this in any mode, any conditions, even stationary. The mechanic said this isn't a problem, its all fine. Problems are yellow. OK, so I drove home. Well, the owner's manual says that this indicates that the ACD has gone into self-protection mode, caused by extreme circumstance, usually under extreme driving. Apparently I have mastered the art of being stationary...to the EXTREME! So I decided to do a little research, thinking the technician must have been just a little bit lazy on this day. Here is what I found out:

The new flash changes the screen for the initial error (C161E, pump failure). Since the screen above indicates "STOP NOW", I guess they realized that there is no safety or mechanical reason to stop, so lets make it a minor error and people will drive to the dealer eventually. Another error now also shows up, C161F (ACD fault, protection mode). I think that is what blinks the ACD mode.

So what is wrong? I don't have a MUTIII in my garage, and didn't want to pay for more diagnostics that the mechanic should have already done. So I searched online for ways to test. First: test if the pump is building pressure:

1) pull of the rear bumper
2) back right, you will see the pump. Disconnect the biggest connector (power) While there, also make sure the connections are not corroded, and clean.
3) using a batter, apply 12V to the pump (black is - ).
4) listen: if the pump is building pressure, the pitch should drop as more resistance is encountered on the impeller. After 30-40 sec (maximum), if pressure has been built, the pitch should suddenly go high again as the pressure reaches max and flips the relief valve.
5) as well, if pressure is building, then the fluid level in the reservoir (in the trunk, right side), should drop as it fills the accumulator.

Mine never did this. The pressure is not building. Clearly, things are not fine. But maybe the computer controls a valve to tell pressure to go up? I need a better test, I need the car on. But how do I do this? Like so:

1) jack the car up, and put it on 4 stands so the wheels are off the ground (maybe just tell your mechanic to lift it, please don't hurt yourself)
2) start the car. Do not put it in drive, but the e-brake should be released.
3) Go to the back right (so you can hear stuff)
4) With your hand, spin the wheel (wont need to go far).

Provided the ECU is working, the pump should start, as it assumes the traction condition has changed, and tries to adjust the ACD. It will run for about 20-30 sec, then quit. At the end of this, your ACD mode will be blinking again. YAHOO! Situation replicated, and proved the computer isn't faulty.

See, it turns out the computer does not regulate pressure, at least not at the pump. So, it just tells the pump to build it, and makes sure it reaches a threshold. It is either there, or it is not. The pump builds it, and should do so within X time. If this isn't detected by the computer, it gives the blinky error.

So now you are saying "But supr! Couldn't this be a sensor?" Sure could! The sensor is located at the pump. And Mitsu sells the pump as a single unit. Therefore, the pump is still the problem. However, since the pitch wasn't changing, and the fluid in the reservoir wasn't moving, it isn't a sensor.

So back the dealer I do, armed with my new info. My plan was this: Get them to test the pressure, either through the MUTIII, or through a good old fashioned bleed test (if it is pumping, the bleed nozzle will **** out fluid like a drunk after a new years party, if not it will be more like a 70 year old with a prostate problem). If the pressure built, then swap the ACD ECU with a known good car to verify it isn't the computer (just to test, I'm an IT guy and this just seems right).

So they discovered since the last time, that there is a new TSB for this condition, with 15 page diagnostic instructions, and went through that instead. And then called Mitsu phone support for more answers. And then compared with a working unit. Turns out I'm only making 1psi in the pump. It should be 192psi. A little bit different. So after all that, they proved what I thought. The damn pump is broken.

So what now? New pump. I'm going to eBay one, and hope it is good (save me some $). But this is a heads up for all you AWD lancer drivers (Evo X and Ralliart), that if you see that screen, or see that blink, get it checked ASAP!

And why is this important to Toronto? I have read repeatedly, from Evo 7+, that this issue may be caused by corrosion on and in the pump. We salt our roads, and that isn't friendly to the aluminum pump, so you will more than likely encounter this issue eventually

I'll post again when the new part arrives, and let the internets know how it goes.

*************
I'd like to take this chance to thank Mitsubishi Newmarket for generally being awesome. I think their technician has some things to learn (like not all problems are solve on a computer alone), but they have been really good throughout the life of my car. In fact, for today's diagnostics, which took almost 2 hours with the learning and the phone call, I was not charged at all. Pretty good, considering the car is well passed warranty. Many thanks, its been good.

cross posted to my BLOG

Originally Posted by TrailBrake

I have nothing written, but I can confirm being told by a dealer that the ACD pump is not covered by the powertrain warranty.

Originally Posted by GTE28

suprPHREAK, how long did it take for Newmarket to confirm the ACD pump was toast?

Originally Posted by suprPHREAK

.....I got it from eBay, I searched by part number.....

Originally Posted by EVLEVOX

What's the part number? My pump appears to be dead as well, and I'm looking into alternative sources for a new pump.....

Originally Posted by Ruff-Shaw

I am selling rebuild kits for the Ralliart and EVO X pumps. The kits are running $200. We can also rebuild pumps for guys in Canada. We’re in the GTA, so you can even pick up your kit or drop off your pump for service, if you’re close enough. If anyone is interested, you can PM for details. Here is a link for the Evo kit, but as I mentioned, we have Ralliart kits too. Cheers!

http://www.ebay.ca/itm/Mitsubishi-EV...77804b&vxp=mtr

Originally Posted by Ruff-Shaw

We test the pump before it’s disassembled and then we test each part on its own after. All pump parts are carefully inspected, plate upgraded to stainless, internal o-rings discarded and replaced with brand name ones, bolts are discarded and replaced with new ones, solenoids are tested and solenoid o-rings are replaced.

We also test motor winding coils, brushes, bearings, shaft tolerance, bearing housing, couplers and inserts between the motor and the pump. Motor rewinds are also available, so if something can’t be fixed it can be sent it over to us so for inspection.

The pump body gets cleaned, sand-blasted and then painted with clear epoxy coating. Finally, the assembled pump is bench tested for pressure, running OEM fluid and using OEM reservoir and hoses.

All parts and materials are brand name and all service is done in house.