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Agreed regarding staying out of S6.
I now stay in S5 M-mode all the time and only use the SprintBooster's green setting.
No issues.
So what do you think? New thread? I could use the potential education/entertainment (depends upon the responses).
 

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Discussion Starter #22
I am going to try those settings for awhile. The failure rate for me at least is so low it's hard to get a conclusive answer. Last year I was getting and engine fail-safe for exhaust cam over-retarded at the track. I swapped the vanos solenoids, cam sensors and added a FAMS tune. That one has not come back but I would not be surprised if it did.
 

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Also agreed on the extremely low failure rate.
As well, I have never been left stranded (by a SMG issue).
I have only had what I call occasional SMG spasms (less than a handful of times over the yeasimes a year) and each time they either clear themselves or go away after resetting with Carly or BMTechnic.
 

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Discussion Starter #24
Well I wasn't sure where to drop this will all the other SMG problems on the forum. I figured that following up on my own thread would be best.

So my last failure was staying out of S6 and switching the sprint booster to green. The SMG would fail and go to auto mode and then recover and allow me to shift manually. I was quite a ways from home so the short story is by the time I got home the car was locked in 4th gear and the car stalled when I stopped in the driveway, no throttle response at the end. If I were a guessing man the HP pump timed out and the car shifted until all the pressure was gone.

The codes were the usual, 40, 42, 43 and 510, all HPU related. So last winter I had the exhaust and drive line out for the front main seal on the rear diff. At that time I pulled the HPU motor and cleaned it up, replaced the relay, seals and fluid. The slave cylinder was done with the clutch about 17k ago at this point. It was working fine even through a 4000 mile road trip and a track day at thunder hill. The last thing I did before I shipped out for two months was a Euro SMG tune. I drove it a few short times with no faults.

Now I'm home two moths later and on my first track day the SMG failed several times in a few laps until the car locked up and had to be towed home. So yesterday with more beans in my head I took a closer look at the data. After resetting the SMG when you open the door you can hear the pump cycle. It pumps up to about 62bar and takes just over a minute to cycle back on at 48bar. According to the SMG society that is about normal for a good accumulator. When I reduce the pressure it looks like the big drop comes at about 30bar which would also mean the accumulator is good. Then while changing the oil I checked for leaks and topped off the reservoir.

Short of either replacing the seals in the SMG until or sending it out I'm going to go back to the US SMG tune. It all started after that and it's a free test. Of course I could throw another relay at it for the heck of it but it would appear that it is following orders from the SMG controller.
 

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If you really want to troubleshoot download testo and log pressure vs. pump status (on/off). Bet you'll see an 'on' status without an increase in pressure before it fails. Which would prove it's your motor - again.
 

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Discussion Starter #26
Darn it I did not want to hear that. I did consider a new motor except that everything has been fine before and after until I put the Euro tune in. Whenever we have a failure on the ship we always go back to the last thing we touched. It's also cheaper than a motor.
 

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Good luck Alan.
I will continue to follow but I have nothing more to add.
(But I am still staying away from S6)
 

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Actually you may on to something here... Can you post the full codes? I think one of the 510x is pressure sensor which can be firmware related. Pump alone should not trigger a 510x code.
 

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Discussion Starter #31
Yes a clean up, plenty of brush left.

So I took the car for a spin with INPA running. One thing I noticed right away was that the cycling pressure bumped up. It started at 62bar and when up to almost 80bar with the temp at 20c. By the time my drive was over it was 62bar up to 90bar at 85c. The pressure would bleed off much fast of course but I had no faults on my 40min drive.

I think it's just a bunch of old worn out o-rings. I will change the tune and recheck the pressures. I would not put it by some capitalist to soften the faults to keep a car out of the shop. With that done I will throw and accumulator at it mostly just for the hell of it and because it's easy. After that will be a full control system replacement or rebuild. As far as I know it's 14 years old and has 117k on it.

One last thing I may try is a different fluid or some type of additive. My Dad used to do it all the time on old automatics with good results. If I am going to overhaul the system I don't really have anything to loose.
 

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Discussion Starter #33
I did not scrape the stampings. You don't miss much do you?

Based on my observations the pump is running as it should. I of course could observe it for longer but I think the pressure drop and cycling frequency is high, less than 30 seconds with the oil hot, car running and parked with no commands. The saga will continue with systematic replacement of parts at an ever increasing cost until I'm satisfied that the problem is resolved.

Before I committed to this platform I accepted that one day this would happen and I'm prepared and committed to fix it. That's half the fun.
 

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Lol... In my old motor it was the stampings causing the brushes to get stuck in their holder. The refurb motor diy post showed the same thing. Either yours is the exception or you'll fix them soon haha...

One observation I had when I installed a new motor is that new brushes slid freely through the stamped section. I suspect the stampings weaken the brushes, somehow causing them to bulge in that area given time and spring pressure. Just a crazy theory based on what I saw...
 

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A-ha,so 520a not 510x. That one is set whenever I use ista. And ista ignores it even, but shows up in inpa. Either way unrelated, I'd bet money on your pump motor.
 

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Discussion Starter #39
Well here's what I discovered, take or leave it.
I put the US SMG tune back in. I noticed right away that the cycle pressures are lower. I started with oil at 17c and it took 2.5 minutes for it to cycle with the engine off. With the engine on it did not change. The big difference is that the pressures were 43 and 65 bar. When I last checked the Euro tune in neutral with the engine running it was 78-90bar. Higher pressure, more leak-by, more heat.

I had my son watch the cycle pressures as I drove in 5th gear at part throttle. Each increase in shift mode had a corresponding increase in pressures. The first two bars were 43-65, the next two bars were 45-75 and the last two were 58-80bar. So being in S6 definitely would increase the pressure literally and even more so with the Euro tune. The DSC had no effect on the pressures, P500 had no effect on pressures. The sprint booster does have an effect but maybe not the way you would think. The booster amplifies the signal from the throttle so if you have a soft foot the car will still drive like a raped ape. The effect that this has is that the SMG monitors the pedal position and torque values of the engine. If you put your foot into it, the pressures will increase as the car is expecting a shift at high load. I directly observed this.

So for me the Euro tune is out. A 4000rpm launch is not on my list of things to do all the time. I have no idea what the timeout period is for the HPU but I have emailed Jim about a delete. There is no doubt that my SMG is old but for now to spare me a $3000 bill and a tranny pull I'm backing off. I'm going to try and get on the track Thursday and see if I am full of $hit or not. An oil upgrade and maybe an additive are on the list. I think the pump, motor and rely are fine. Tomorrow I will be looking into a way to get some cool air to the HPU to bring the temps down. 75c at the end of the drive today and 85c at the end of the last drive with the Euro tune.

If you are having HPU fault codes consider dumping the Euro tune if you have it to lower the pressures. Make sure the oil is fresh and the relay and motor are good to go. Short of that you will need to get the control unit rebuilt or replaced. And don't for get the slave cylinder. The SMG is great for it's vintage and the motor is awesome of course.
 
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