2006 Z4M Electrical Gremlins/Introduction

[Jamxx]

Hi all,

Purchased my friend's 2006 Z4M Coupe in July of this year with right over 100k on it and have been loving it ever since. I do have a couple of issues with it at the moment, and after searching the Internet and finding no real conclusive results, I decided to post here.

1) When car is at operating temp., sometimes the starter won't work. I can hear the solenoid move, but that's it. Usually the 4th or 5th try it decides to start, sometimes it takes it a few more and sitting for a few minutes. This has happened to me five or six times since I replaced the alternator (Valeo unit) a few months ago. I have a new Valeo starter sitting around but I'm a bit afraid to attempt to install it - mainly worried about pulling the intake and exhaust off (some people say you do have to unbolt the manifold, some don't, I could never find a straight answer).

2) On one occasion, the car has died on me right after merging on the Interstate. I admit I was giving it the beans, but shifting at only 4-5k each time. All of the sudden the engine quit on me and all gauges except the speedo quit working, and at the same time the battery and oil light flashed very quickly for a few seconds and then the dash lit up like a Christmas tree. I pulled over in the emergency lane, turned the key off and she started right back up as if nothing had ever happened. Drove it home and have had no other instances of this happening since. A bit disarming!

Other than that, it's been pretty smooth sailing once I got the alternator replaced. That was causing all sorts of weird behavior. Easy to do as well, had it done in about an hour.

And here's one good and some bad pictures of it. I also have an MSTACHE 2 lip on the way (thanks Steve!) that I'm going to try to wrap in carbon fiber vinyl (3M 1080 most likely, seems like the stuff to use) in addition to the two small fins on either side of the bumper. I think it will really tie the car together!

Before I owned it:



Day I bought it:



After I got new tires and the wheels re-powdercoated (they look good in the above photos but they really needed it):



My other car, bagged big turbo big booty Jetta (currently dead but on the path to recovery ):



And sadly usually what's my daily :



Cheers and thanks for the help!

Jamie

[polar]

Hi! Nice collection of vehicles, not practical at all, exactly how it should be!

Regarding your electrical problems, I would start by checking the battery. The terminals can get loose which result in bad charging, corrosion around the (-) terminal and system hiccups.
If that's not the problem, it sounds exactly like a bad ground connection.

[Jamxx]

Luckily my daily commute is all of 5 minutes so I don't have to worry too much about gas mileage!

The battery was replaced earlier this year by the PO, but I have not checked the connections closely. I will make sure the battery connections are tight and that everything looks good in the small power distribution block located next to it. I'll also check the resting and charging voltages at the battery and report back.

Thank you Polar!

[chickdr]

The starter is the key to the first issue. I would go ahead and tackle that one. Then do the battery work as suggested above. From there it may take some diagnostics if that doesn't fix it.

[elerner61]

Jamie, you may want to try swapping the ignition switch first as it is cheap, easy and fast. The combination of the intermittent starter AND the car cutting out AND other gremlins is what's got me thinking this way. http://www.zpost.com/forums/showthread.php?t=716472

[Reborn_]

Originally Posted by Jamxx

Luckily my daily commute is all of 5 minutes so I don't have to worry too much about gas mileage!

The battery was replaced earlier this year by the PO, but I have not checked the connections closely. I will make sure the battery connections are tight and that everything looks good in the small power distribution block located next to it. I'll also check the resting and charging voltages at the battery and report back.

Thank you Polar!

Agree with this. Most likely culprit is loose/dirty/corroded/damaged terminals and/or cables. I had the same car shut-off-start-back-up happen to me on the highway (not in my M) and that was the root cause. It could certainly be the root cause to all of your issues.

Start by cleaning the battery terminals and the cable ends. Replace them if necessary. Smear with petroleum jelly (vaseline). The jelly will prevent corrosion and also acts as a dielectric grease.

[elerner61]

Be careful to not over tighten the battery terminal nut (positive terminal specifically). It is possible to snap the piece that it connects to which cannot be purchased separately, requiring the purchase of an entire positive cable (expensive).

There is a picture and torque spec. in the first post of this thread: http://www.bimmerfest.com/forums/sho...d.php?t=609849

[Ryan13]

Similar issue on my 2006. Cold start...no issue. Run the car for 15 minutes and shut it off...nothing. Open the hood after 15 minutes of running, let it sit for 15 minutes, starts right up. We ran a jumper straight to the starter to eliminate all the wiring in-between...on a hot start, nothing. Checked everything else just to be sure. The starter was getting heat soaked and would not work when warm. Replaced and all is good. I thought the ignition module may have been the culprit, but when we ran power straight to the starter and it did not work, we knew we were looking at replacement.

[NickyC]

Glad to see somebody finally bought that car! I was surprised it lasted for sale as long as it did with all the high dollar mods it had done to it. Enjoy!

[Jamxx]

Originally Posted by chickdr

The starter is the key to the first issue. I would go ahead and tackle that one. Then do the battery work as suggested above. From there it may take some diagnostics if that doesn't fix it.

Yeah, I just need to find the time to do it. I know that this will be $$$ from a shop, plus I already have the starter. Are you aware of a Z4M specific DIY for this just so I know what I'm getting into? I was unable to find one specific to the Z4M.

Originally Posted by elerner61

Jamie, you may want to try swapping the ignition switch first as it is cheap, easy and fast. The combination of the intermittent starter AND the car cutting out AND other gremlins is what's got me thinking this way. http://www.zpost.com/forums/showthread.php?t=716472

I'll keep this in mind, certainly doesn't seem to be a tough job. Since I already have the starter, I feel like that's the logical first step, but if I continue to have issues I will keep this in the back of my mind.

Originally Posted by elerner61

Be careful to not over tighten the battery terminal nut (positive terminal specifically). It is possible to snap the piece that it connects to which cannot be purchased separately, requiring the purchase of an entire positive cable (expensive).

There is a picture and torque spec. in the first post of this thread: http://www.bimmerfest.com/forums/sho...d.php?t=609849

Good to know, I'm generally pretty careful to not overtighten stuff. Broke a transmission mount bolt on the Jetta that way, that was a pain in the ass to fix!

Originally Posted by Ryan13

Similar issue on my 2006. Cold start...no issue. Run the car for 15 minutes and shut it off...nothing. Open the hood after 15 minutes of running, let it sit for 15 minutes, starts right up. We ran a jumper straight to the starter to eliminate all the wiring in-between...on a hot start, nothing. Checked everything else just to be sure. The starter was getting heat soaked and would not work when warm. Replaced and all is good. I thought the ignition module may have been the culprit, but when we ran power straight to the starter and it did not work, we knew we were looking at replacement.

Pretty sure the starter is succumbing to heat soak. I am aware it is a known issue. Just gotta do it!

Originally Posted by NickyC

Glad to see somebody finally bought that car! I was surprised it lasted for sale as long as it did with all the high dollar mods it had done to it. Enjoy!

I actually bought it from my friend who bought the car from the guy you are probably talking about. My friend traded his supercharged 700 whp C6 Vette for it. We have been wondering what he has done with that thing since my friend traded it away! I believe I am the 5th or 6th owner of this car.

Thank you ALL for helping me out with this! I will try to update the thread as I accomplish these suggestions.