Rotator

Currently I have a nagging DTC that gets thrown. Not a problem with "M" flash, now with "N" flash results in engine not going past 3000rpm - LIMP mode.
Now the DTC's thrown are all P1686, P1687, or P1688. No drive by wire sensor codes.

DTC's are:
P1686 Metering oil pump control circuit low flow side problem
P1687 Metering oil pump control circuit high flow side problem
P1688 Metering oil pump control circuit initial check problem

From what I can determine, there really aren't that many things that can go wrong.

Description of the Metering Oil Pump:

• An electric metering oil pump has been adopted to reduce oil consumption by controlling the amount of oil discharged.
• The electric metering oil pump is controlled by the PCM.
• The PCM sends a pulse signal controlling the amount of oil discharged to the metering oil pump according to the engine rotation, engine coolant temperature, and the amount of intake air

Basically a simple stepper motor with drivers in the PCM and a switch that turns on at a specific point of the motor (52 steps).
What can go wrong?

Potential Blockage of oil nozzles in rotor housing?
Drive by Wire not working? Why no DTC's?
Pump Switch not functioning.
Vacuum hose leak?

What has been tried - Replaced MOP 2X, Replaced PCM 1X. Checked wiring.
Why is the car in LIMP mode.

Information on LIMP mode, or the Fail-safe function :
• Fail-safe function operates when the engine senses a failure in the stepping motor and the positioning switch.

• When the fail-safe function operates, the PCM keeps the control pin at the minimum stroke position and the oil supply is only in proportion to the engine rotation rate. Thus, the minimum amount of oil at each engine rotation rate is supplied.

• Normal driving is possible when the amount of the oil required by the engine is within the minimum oil discharge.

• When the amount of the oil required by the engine is more than the minimum oil discharge, fuel injection is restricted, increased engine rotation is suppressed, and seizure of each seal inside the engine is prevented.

How long can you drive in Fail-safe mode before something bad happens?

Ideas? Anyone?

Gomez

Lets see. Have you modded the car at all, disturbed any wiring, installed an alarm etc? Have you pressure washed the engine? How old is the car...who's worked on it?

With the PCM having already been replaced, I suspect a faulty connection somewhere. Has the wiring to the MOP been checked for condition and security?

Gomez.

Rotator

No Mods, No PCM change or modding. No intake, no exhaust, no FI.
I have an amplifier and a sub - but can't see that doing anything as it has been installed for many months without problem.
Right now I am suspecting the wiring harness between the MOP and the PCM is at fault and should be replaced. Talked with a tech that is currently working on my car at another dealer, and he said he has had an electrical gremlin that was solved by replacing the harness.

From what I can tell, there is no pressure transducer between the MOP and the oil injectors - so the PCM would have no way of knowing whether or not the volume of oil to the nozzles is sufficient.

The air hose to the oil nozzle may be pinched, or blocked.

All I can say is fail-safe operation is a bummer. Engine will no go past 3300 rpm, and takes forever to get there.
Shifting at 2000 rpm results in acceleration slower than a bicycle, but allows 4rth to reach 50 kph or so.
No flashing MIL to indicate fail-safe mode.

Gomez

You said in your first post that the PCM had been swapped out. So was it, or not?

It's either the PCM or the wiring between the PCM and the MOP, IMO. You didn't answer whether the engine had been pressure washed or not. Occasionally water can get into connectors and cause problems.

Gomez.

Rotator

Gomez,

I only know as much as the dealer told me.
So far MOP replaced 2x, PCM 1x. So the likelyhood that 3 MOPs and 2 PCMS are faulty is slim to none.
All three times the car entered fail-safe mode was from a stop.
This indicates tha the MOP control circuit was in regular drive function and the PCM didn't detect the MOP position switch going from on/off when the stepper passed through position 52.

As for pressure wash? Nope. First time DTC came up was on a -23C day - even says it in the freeze frame data from the PCM.

I would have thought their people (MAZDA) could figure out the operation of a stepper motor - there are only 8 friggin wires to figure out.

Replace the harness and give me my car back! 3 Weeks and counting.

I appreciate the ideas though!

Mr M

Sounds like a tricky problem, I admire your patience.
It sounds like the failure is occurring when the MOP self test takes place at engine start up, like you say.
I have produced these same three DTCs by shorting two of the stepper motor coil wires (I did it for training). The problem will be hard to reproduce because it only happens when starting the engine, and theoretically the self check only happens every 12th start (although it occurs every consecutive start sometimes, don't know why), which gives you even less chance of reproducing it.

Seeing your car is probably still under warranty, I think that the dealer might have grounds to replace the harness. For the time it would take to inspect the harness it would cost Mazda less to replace it. All the background information is there (previous, unsuccessful repairs) so they have a good chance of the claim being approved. If not, their only choice is to get their ohm meter out and start wiggling wires!

Cheers

Rotator

Mr. M,

Yes the car is under warranty - and supposedly they checked the harness.
My idea? Use the KOER tests, or any other tests available for the MOP with the WDS and while the stepper is cycling from 0-60 steps wiggle the harness.
It may be difficult to get at when the battery is in place though.
But 3 weeks for this problem? Come on.
The MOP has 3 modes of operation - I don't know why they didn't include a simple potentiometer position feedback, or a couple hall sensors at the each end of stroke for the motor to verify position is beyond me. Having a simple switch at position 52 just isn't enough. I really don't understand Fail-Safe mode and how the stepper motor can be placed at position 7 if the stepper is thought to be siezed, or not functioning as verified by the switch.
Initial set - every start
Monitor function - every 12th start or new battery connection.

Gomez

Well if the MOP and PCM have been changed multiple times it sounds like you're up for a harness. Trouble is, they wouldn't normally keep something like that in inventory stock. Might have to wait for it to come in from Japan.....here's hoping they sent it by air!

Good luck,
Gomez.

Rotator

Air? I see postings on this board with people waiting months for stuff to come from Japan - small items like keys. If that is the case - they better set me up with another 8, AND cover my LEASE payments for the term. They are soo friggin' cheap that they will send the harness find some bum with a Junk - give him $2.00, a MAP, a paddle and a compass!

My biggest Gripe? They (Mazda Canada or the Dealer) is not telling me anything.
So I don't know what the plan is now.

Mazda - are you listening?? 3 weeks+ for this type of problem? Has to make you wonder what type of geniuses work there.

Rotator

Update - NO MIL after 150km's. Eccentric Shaft Plate Profile Problem?
Cleared DTC's
Cleared KAM (Link Here ) - Battery disconnected for 30 seconds, Brake Pedal 20x in 8 secs, Oil Needle Sweep Confirmation.
Fixed? We will see.
PCM software - SW-N3Z2EN0000
Do you need to reset the KAM each time the PCM firmware is upgraded?
The PCM does use the Eccentric Shaft position as an input for the MOP control circuit.

Gomez

If the KAM does have to be reset, the dealer will have done it after the upgrade and prior to you picking the car up.

This doesn't make sense. The car had a PCM change.....a new PCM has no stored DTC's so clearing the KAM now shouldn't fix the fault!

Rotator

Gomez,
Clearing the KAM have an affect? Don't know - So far so good - I am around 360km's since it was reset and no MIL or failsafe mode. "N" has made shifting smoother, as it got rid of the high rpm upshift under acceleration that the "M" version had. I like! Also of interest - Clean tailpipes - went 120km's on hwy - tailpipes still clean! no carbon! Does "N" contain a reasonably lean fuel curve? Wonder if my CAT is going to melt now. Wish I had a logger.

Problem summary :
MIL ON - P1686 Car operating FINE - reset DTC, reflash from N to M - enter failsafe mode within 100m.
Replace MOP - same issue - Fail-Safe
Replace PCM - same issue
Replace MOP - Again - same issue - Fail Safe
Harness checked for continuity and loose wires. There are only 8 between the PCM and the MOP.

Since the "N" reflash the car entered fail-safe mode 3 times - each time leaving from stationary - 20% throttle. The longest it made was about 50km's

Since the last KAM reset by first disconnecting the battery, then performing the reset - the car 360km's without a since DTC. Does resetting the KAM in this manner make sense as a fix? Are you required to pull the PCM power first before resetting the KAM, or can you do it at every IGN ON? I beleive the oil pressure needle sweeps any time.

Will keep this thread posted with the results.

Rotator

Update on Problem - May 4, 2005
Vehicle enters Failsafe mode for 5th time.
Back on Flatbed to dealer #1 again.
So far out of the last 44 days since first problem, 32 days have been at the dealer.
"Fixes??" in order

Requested replacement RX-8 as fix is not eminent - denied.
No offer of any other compensation.

Summary
3 dealers, 44 days and counting without a fix for the same problem.
5 times - fixed? then broke - 2 times I didn't make it out of the dealer lot, 1 time I made it 20km's then the other 2 times about 750km's.
No replacement vehicle offered.
Buyer beware.

Go48

Do you have a lemon law in Ontario/Canada? If so, it's time to consult an attorney. In the states, it's usually 3 times at the dealer for the same un-fixed problem and the lemon law kicks in. Check on it. You've got a lemon!

snap-on

While I feel for this guy, the only thing I would question is why he didn't take it back to the same dealer for the same problem?

The history of the entire process would be there. They would know what tests were run and re-open the file on the hotline.

If his account of service days is correct I don't see why Mazda won't get involved.

Rotator

Go48 - No specific Lemon Law in Canada - We do have an independent Arbitration program called CAMVAP .

Snap-On - With the first dealer having the vehicle for over 2.5 weeks with no resolution - and also scratching, denting, and breaking things, not to mention total lack of communication, no response to voice mails, etc. I had my reason to try another dealer. Plus I also had an open service case file, and I had all of the WDS printouts from my PCM including freeze frame data - All this data was provided to the next dealer by fax even before my car arrived on a tow truck.
That, and the first dealer couldn't get my car in on the weekend. I have a dealer close enough to push my car to - but I won't let them touch it! Again - I have my reasons.

Mazda Issues? Biggest problem is what Snap-On states - the service records are with the dealer. Head office really doesn't have a record of warranty service until the dealers submit for reimbursment. Even then the records are usually so poorly worded that it is near impossible to find a correlation between the events.

In my case, the records from 3 different dealers indicate 3 different problems - all resolved. Despite me providing an open corporate case file #, and detailed description of the problem including the DTC codes that were thrown.

So what do I make a point of? Getting any WDS printout, talking to the tech to find out what he did, when he did it, why he did it, and under what direction.

Gomez

And it seems it didn't..!

So we're back to where we started.....MOP harness. Sorry to hear you are still having trouble with this.

Regards,
Gomez.

Rotator

Gomez,
Thanks for the sympathy
MOP harness, OR the big unknown - software glitch?
Running "M" flash - DTC present but no failsafe mode - no drivability issues other than a slight hesitation on high rpm upshifts.
Reflashed to "N" - DTC AND failsafe.
Things that make you go - hmmmmmmmmmmmmmmmmmmmmm.

snap-on

No Hmmm,

Maybe some leg work.

If the dealer had a claim to file with Mazda (according to Mz P&P) they should have had the invoice with all work performed ready for you to sign when you picked up the vehicle. Go to each dealer and talk to the Service Manager and if he won't give you a copy go to the GM. This document should show any parts and labor including in addition to any "tech notes" they used to justify the claim they filed.

As far as the Mz system goes..Mazda pays dealers twice a month on claims. If you have more than one claim in one month it is possible that I will not show in Mazda Canada's system yet. Unpaid claims will not show on the "VIN" when the customer relations rep runs it. All claims are put in "suspend status" until it is reviewed and paid. They are not at fault here...yet.

Once you get your paperwork you can call Mz again and offer to provide any paperwork they don't have.

Good Luck.

Get your paperwork and det back to us..

Rotator

Snap-On
Thanks for the insight into "the system"
As for service orders - Note that the dates of the invoices are all on the day I am told the car is all OK, and ready to go.
I have service records from 3 dealers.
Dealer 1 - Day 1 (reflash), Day 16 (MOP 2x, PCM), Day 17(PCM reset).
Day 1 - Didn't make it out of lot before MIL, Failsafe.
Day 16 - Didn't make it out of lot before MIL, Failsafe.
Day 17 - Drove 18km before MIL, Failsafe.

Dealer 2 - Day 21 (Reset KAM) - no mention of MOP -
only handwritten notes from Tech.
Day 27 - Made it 785km before MIL, Failsafe.

Dealer 3 - Day 29 - (Found loose GND wire)
Day 43 - Made it 751km before MIL, Failsafe.

Every dealer hooked upto the WDS to get freeze frame data.
Each Freeze frame data indicated same DTC's P1686, P1687, or P1688.
I made a point of getting the WDS printout for my records.

Dealer #2 had the worse service records - Even though I requested a correction 2x to ensure there is a link to the problem from Day 1, and dealer #1.

Delaer #3's service tech could not reset the MIL until he found the loose ground wire from the PCM. I talked with him for some time about his measurements - Didn't make sense.

Every time I had returned the car, I came with FULL paperwork from previous service including any of my notes, open case files, etc.
I also provided Tech Names, Service Manager Names, and any supporting information I thought would be useful to diagnose the issue.

I opened my file to the dealer and told them they could copy whatever they thought appropriate.

Today marks day 47 without a resolution in sight. During those 47 days the car has entered the dealer lot - 6 times for the same problem. There it remains.
As I see it - there have been MANY attempted fixes without resolution.

Lemon Law?? Incompetence? Software Glitch?

Whatever it is - I am paying a lease+insurance to have a 2004 RX-8 sit in dealer service bays. Fair trade?
Mazda Canada hasn't come forward with any offers.

Current Theories?
as all of the mechanical and electrical tests have been performed.
Software Glitch? or Wiring Harness (unlikely)

Gomez

Diagnosing wiring faults is a specialty of mine. Wiring is quite often the last place to go looking for a problem. Sometimes however, it should be right up towards the top of the fault finding tree. Breakdown of wiring integrity is more likely in high vibration and high heat areas.

Vibration can cause wear between the pin and the socket at connectors....breaks at stressed areas of the harness, and intermittent failures that clear for weeks at a time. Heat adds to insulation breakdown and heat cycles expand and contract points of intermittent contact.

Almost everything else has been tried. Get that harness replaced.

Gomez.

Rotator

GOMEZ - Day 52 - RX-8 still disabled - Wiring harness on Order.
3-5 days to get it.
PCM connector has 27 contacts, MOP has a 6 pin, and 3 pin connector.
Dealer performed "WIGGLE TEST" on wires many times - could not find any continuity faults.
This car has been through a whole winter of salt spray.
Salt is nasty - and likely caused some insulation breakdown somewhere.

Time will tell.

If it's not the harness it is a software issue - unlikely as there would be many more disabled vehicles. Tried reverting back to older firmware - didn't fix it.

Wanna buy an RX-8? It's pretty.

Wurmfist

If this happened to me in Ohio, and I know it's been said before, I would so be using the Lemon Law. I'm sorry you are having to deal with this. They need to give you a new car. 52 days is unacceptable. I'm in the repair business and you can wiggle wires all you want and may or may not find the open. Try changing this wire harness:

Gomez

Time's up, mate!

Any news on the harness??

Rotator

All who have been following:
Last event was May 4 - Car entered Fail-Safe mode so I had it towed to dealer #1 - AGAIN.
Dealer #1 takes over 1 week before they even order the wiring harness.
Then the harness - in stock in the US - takes 1 week to arrive.
Wire harness in May 20th, 2005.
Problem first arose March 22, 2005.
That is 60 days by my count - if you include the 22 of March.
Fail Safe Mode entered total of 6 times - all 6 have freeze frame data
MOP replaced 2X, PCM 1X, Wiring Harness 1X
It really burns me that the WORKSHOP MANUAL even suggests replacing the wiring harness - wiggle test? What use is that?
Car now functions - over 300km so far - Let's see if she'll make 5000.

Other issue? I now have a new rattle that wasn't there before and a mysterious bend in my rear tunnel member (cross brace for the power-plant frame)
Who knows how, and what other damage has been caused.