[Chief Orman]

Was cruising along at 80 mph and punched it. Water meth kicked in and I got a strange and disturbing shudder from the driveline. My gut tells me it is not the tranny. Got new tires recently from a crappy but cheap tire shop. I decided to get my tires road force balanced and they were slightly out of balance... not huge, but out of balance. I think it might be the driveline... specifically the drive shaft but I am reluctant to retest for fear of blowing up my driveline/transmission.

Road force balancing was a good move no matter what... car now drives like it is on glass.

Any ideas would be appreciated.

[NC335d]

Originally Posted by Chief Orman

Was cruising along at 80 mph and punched it. Water meth kicked in and I got a strange and disturbing shudder from the driveline. My gut tells me it is not the tranny. Got new tires recently from a crappy but cheap tire shop. I decided to get my tires road force balanced and they were slightly out of balance... not huge, but out of balance. I think it might be the driveline... specifically the drive shaft but I am reluctant to retest for fear of blowing up my driveline/transmission.

Road force balancing was a good move no matter what... car now drives like it is on glass.

Any ideas would be appreciated.

It could possible be related to the water/meth system pump or controller, especially since you "punched" the throttle whilst going 80 mph. That happened to me once, when I wasn't paying attention to the low level of fluid in my meth tank during a joyride to work one day. My tank was bone dry at wide open throttle and the intermittent drops of what was left in the lines caused my car to shudder like that.

Just a thought.

BTW, still enjoying the Ohlins??

[Chief Orman]

Originally Posted by NC335d

It could possible be related to the water/meth system pump or controller, especially since you "punched" the throttle whilst going 80 mph. That happened to me once, when I wasn't paying attention to the low level of fluid in my meth tank during a joyride to work one day. My tank was bone dry at wide open throttle and the intermittent drops of what was left in the lines caused my car to shudder like that.

Just a thought.

BTW, still enjoying the Ohlins??

Going to check my tank in the am.

Ohlins are still fantastic! For those of you who enjoy firearms, it is the Sig Sauer P226 of suspension components.

[Hoooper]

Originally Posted by Chief Orman

Ohlins are still fantastic! For those of you who enjoy firearms, it is the Sig Sauer P226 of suspension components.

Damn! Already have one, the other wasnt really in my plans but now I almost have to

[CvilleBill]

I have a P226 and trust it. Great side arm. I'm on the fence between Ohlins and the Bilstein B12 Pro-Kit.

[BB_cuda]

There is a part on the front end of driveshaft you may want to inspect. Yozh has mentioned this before possibly causing driveline vibration. He had a nickname for it ... something like a grubber?

[BB_cuda]

This is what Yozh was talking about. item #1. Hopefully problem is just running out of meth/water mix and your u-joint is fine.

http://www.realoem.com/bmw/enUS/show...diagId=26_0233

[Chief Orman]

Originally Posted by CvilleBill

I have a P226 and trust it. Great side arm. I'm on the fence between Ohlins and the Bilstein B12 Pro-Kit.

Ohlins...hands down

[shnaggs]

I have been having the same problem intermittently. I do not have water meth, so it cant be that in my case. It doesn't do it all the time, but sometimes when I lay on it, I get a shudder.

#1 looks like a cush drive of some sort. Hopefully that is the problem. I have read that the gasser guys have issues with the carrier bearing going bad and sometimes causing vibration.

[Chief Orman]

Originally Posted by Hoooper

Damn! Already have one, the other wasnt really in my plans but now I almost have to

If the Ohlins were cheaper they would be the Glock 17 of coilovers.

[Hoooper]

Originally Posted by BB_cuda

There is a part on the front end of driveshaft you may want to inspect. Yozh has mentioned this before possibly causing driveline vibration. He had a nickname for it ... something like a grubber?

Think he called it a guibo?

[NC335d]

Originally Posted by Hoooper

Think he called it a guibo?

Correct. ECS Tuning carries them.

[Mark M]

With our insane torque, I am surprised we haven't seen guibo's being destroyed much sooner. I've killed a couple in my past, one on my former e36M3/4, one on an e28 535, and one on my e30M3.

[TDIwyse]

Originally Posted by Chief Orman

Was cruising along at 80 mph and punched it. Water meth kicked in and I got a strange and disturbing shudder from the driveline. ...

Have you considered that it might be "quenching"? What rpm were you at when this happened? And how much were you injecting and what % of water/methanol?

When I was first dialing things in I'd get a shuddering if I had too much fluid going in at low/medium rpm range and it was a quench issue.

[NC335d]

Originally Posted by TDIwyse

Have you considered that it might be "quenching"? What rpm were you at when this happened? And how much were you injecting and what % of water/methanol?

When I was first dialing things in I'd get a shuddering if I had too much fluid going in at low/medium rpm range and it was a quench issue.

+1 TDI. I have had ZERO issues w/ my drivetrain even with the amount of torque my setup is pushing. I def. think the shuddering is due to the water/meth settings. I had quenching issues when we switched to the new intercooler setup and had to tinker with the settings.

[glitdi]

Experienced this shudder last week under w.o.t. however it made the car go into limp home mode... figured it was more electronic related than mechanical. Anyone else hit limp mode when they experienced this?

[Chief Orman]

Originally Posted by TDIwyse

Have you considered that it might be "quenching"? What rpm were you at when this happened? And how much were you injecting and what % of water/methanol?

When I was first dialing things in I'd get a shuddering if I had too much fluid going in at low/medium rpm range and it was a quench issue.

Great question, but I don't think so. I am running a 50/50 mix which is relatively immune to quenching when I am running it to kick in at 14 psi or higher. That said, I need to recheck to make sure I don't go down the wrong path.

[tc535i]

Check guibo and center bearing if these cars have them

[TDIwyse]

Originally Posted by Chief Orman

Great question, but I don't think so. I am running a 50/50 mix which is relatively immune to quenching when I am running it to kick in at 14 psi or higher. That said, I need to recheck to make sure I don't go down the wrong path.

If your injecting based solely on boost, and this shuddering occurred in the mid rpm region, then my experience would indicate that it's highly likely you're getting quench. These engines can reach their peak boost early in the rpm range...

It would be a simple test where you can modify your controller settings to adjust the injection strategy to see if it's quench or not. Manually shift the car into 4th gear at rpm's at ~1600 rpm and roll on the skinny pedal and see what happens at the low/medium rpm range where boost will likely be the maximum level (assuming you have stock turbos and IWG). I think you'll be surprised how easy it is to induce quench at those lower rpm's...

If you get quench, try adjusting the onset of injection and/or decreasing the maximum injection amount and repeat and see if you can cause the shudder to stop.

This kind of test should be able to isolate if it's quench in very short order.

[iaknown]

Originally Posted by TDIwyse

If your injecting based solely on boost, and this shuddering occurred in the mid rpm region, then my experience would indicate that it's highly likely you're getting quench. These engines can reach their peak boost early in the rpm range...

It would be a simple test where you can modify your controller settings to adjust the injection strategy to see if it's quench or not. Manually shift the car into 4th gear at rpm's at ~1600 rpm and roll on the skinny pedal and see what happens at the low/medium rpm range where boost will likely be the maximum level (assuming you have stock turbos and IWG). I think you'll be surprised how easy it is to induce quench at those lower rpm's...

If you get quench, try adjusting the onset of injection and/or decreasing the maximum injection amount and repeat and see if you can cause the shudder to stop.

This kind of test should be able to isolate if it's quench in very short order.

+1 on this

You can definitely experience quench at over 14 psi if it comes in too fast....

[Chief Orman]

Originally Posted by Hoooper

Think he called it a guibo?

Guys I think the guibo is the culprit. There is a subtle vibration that in the driveline and I think it is probably the result of a lot of hard acceleration runs after I put in my water / meth system.

I have also noticed in the past three weeks that a lot of the guibos are now failing based on the posts of late.

[Nadir Point]

I'm gonna +3 on the quench idea. It took me quite awhile to get my 2-stage dialed in correctly with 50-50. Like TDI said, the twins are pretty much lagless, so boost comes up almost instantaneously. My 2nd stage starts at 20psi.