Z4M Intermittent Start Issue

[yousefnjr]

This issue has been well documented on E46 M3's; since our Z4M's share many components, I'm assuming the causes and fixes are similar. Searching "intermittent start M3" returns countless threads with more or less the same issue, and most haven't been resolved.

Car is a 2006 Z4 M Roadster, 6-speed manual

I was having an intermittent starting issue that has turned into a permanent starting issue. The remote door lock/unlock works fine (within close range at least). When I stick the key into the ignition and turn it to position 1 and 2, I can hear the fuel pump prime and all the lights on the dash are illuminated. My headlights turn on bright. When I turn the key to the start position, nothing happens. Maybe 1 out of 20 times I'll hear a click, but usually nothing happens. The starter is not engaging and the motor is not turning over. Jump starting the car does not work, but I am able to push-start the car 100% of the time. Other people have had success holding the key in the start position for
extended periods of time (2 minutes+), but this has only worked for me once (I held it for less than 30 seconds).

What I've looked at:

Starter -
I've replaced the starter and it helped for a couple weeks, then the issue crept up again. I removed the starter again and had it tested; it passed every time. There wasn't any buildup of gunk on the bendix gear or anything. The
bearings are good.

Battery -
The battery was manufactured in October 2012, barely 3 months old. Using a DMM I can see 12.4+ volts. No excessive corrosion or dirt on the terminals. Of note is that the battery is a lead acid type, which is different than the
AGM batteries that I believe the car comes with. Jump-starting the car with 2 different jumper packs didn't work, so I don't think the issue is charge related.

Power cables -
Using a DMM, I measured 12.4 volts at the jump-start location under the hood to ground. The positive terminal on the starter to ground is also seeing 12.4 volts. From the starter ground terminal to the jump-start post I can see
a full 12.4 volts.

Clutch Switch -
With the key in position 2, I can hear the click of the switch when I press the clutch pedal in and out. It's working.

What I've read it could be:

EWS 3 / Key / Ignition Switch -
I haven't tested or swapped any of these. Since I'm able to push-start the car every time, it doesn't make sense to me that any of these could be the cause. If anybody knows if the car can be push-started successfully with any of
these malfunctioning, please let me know. I'm at my wit's end.

An M3 owner was experiencing the same issue and for him it turned out to be the key. He was unable to start the car unless he tried for several minutes. What was happening was he had his key in the ignition long enough to charge
it, which would allow the car to start. Again, I'm doubtful my issue is with the key, because my ignition works when I push-start the car.

Anybody else experience this or have any ideas? Is there something I'm missing? Is there a relay for the starter somewhere maybe? Any help is appreciated. If nothing else, a recommendation for a good indy shop in the San Jose area that knows M's would be very helpful as well.

Thanks

[elwesso]

I'd be interested if anyone had a downloadable service manual for the Z4..

The first thing in my opinion to check would be the trigger voltage at the starter solenoid. Between the trigger (small wire) on the solenoid and ground you should get battery voltage when you turn the car to crank. If you do, that means the problem has to do with the starter/solenoid. If you do not, then that means it's somewhere in between the key switch and the starter.

I found this image:

http://www.autoparts101.com/wp-conte...ng-Diagram.gif

Looking at the top left of the image, you see the wiring for the ignition switch, and then it says "to starter relay", therefore the starter relay has to be there, although it appears that perhaps the starter relay is only used on the automatic trans versions? Without a proper wiring diagram I'm only guessing. If there is a relay, then a good way to test to see if that's the issue is to take it out and bang it against something a few times. Sometimes relays will even click even though they're not making a good connection inside, and if you can bang on it and it makes the car work, then you know you need to replace your relay (or bang on it every so often.. )

[txz4]

Originally Posted by yousefnjr

This issue has been well documented on E46 M3's; since our Z4M's share many components, I'm assuming the causes and fixes are similar. Searching "intermittent start M3" returns countless threads with more or less the same issue, and most haven't been resolved.

Car is a 2006 Z4 M Roadster, 6-speed manual

I was having an intermittent starting issue that has turned into a permanent starting issue. The remote door lock/unlock works fine (within close range at least). When I stick the key into the ignition and turn it to position 1 and 2, I can hear the fuel pump prime and all the lights on the dash are illuminated. My headlights turn on bright. When I turn the key to the start position, nothing happens. Maybe 1 out of 20 times I'll hear a click, but usually nothing happens. The starter is not engaging and the motor is not turning over. Jump starting the car does not work, but I am able to push-start the car 100% of the time. Other people have had success holding the key in the start position for
extended periods of time (2 minutes+), but this has only worked for me once (I held it for less than 30 seconds).

What I've looked at:

Starter -
I've replaced the starter and it helped for a couple weeks, then the issue crept up again. I removed the starter again and had it tested; it passed every time. There wasn't any buildup of gunk on the bendix gear or anything. The
bearings are good.

Battery -
The battery was manufactured in October 2012, barely 3 months old. Using a DMM I can see 12.4+ volts. No excessive corrosion or dirt on the terminals. Of note is that the battery is a lead acid type, which is different than the
AGM batteries that I believe the car comes with. Jump-starting the car with 2 different jumper packs didn't work, so I don't think the issue is charge related.

Power cables -
Using a DMM, I measured 12.4 volts at the jump-start location under the hood to ground. The positive terminal on the starter to ground is also seeing 12.4 volts. From the starter ground terminal to the jump-start post I can see
a full 12.4 volts.

Clutch Switch -
With the key in position 2, I can hear the click of the switch when I press the clutch pedal in and out. It's working.

What I've read it could be:

EWS 3 / Key / Ignition Switch -
I haven't tested or swapped any of these. Since I'm able to push-start the car every time, it doesn't make sense to me that any of these could be the cause. If anybody knows if the car can be push-started successfully with any of
these malfunctioning, please let me know. I'm at my wit's end.

An M3 owner was experiencing the same issue and for him it turned out to be the key. He was unable to start the car unless he tried for several minutes. What was happening was he had his key in the ignition long enough to charge
it, which would allow the car to start. Again, I'm doubtful my issue is with the key, because my ignition works when I push-start the car.

Anybody else experience this or have any ideas? Is there something I'm missing? Is there a relay for the starter somewhere maybe? Any help is appreciated. If nothing else, a recommendation for a good indy shop in the San Jose area that knows M's would be very helpful as well.

Thanks

had a similar problem for a few weeks. The battery tested fine but for some reason, replacing it did the trick. Ive just come to assume that the M has a certain temperament and decides when it will and wont work properly.

[Finnegan]

Outside of trying what elwsso says, the only thing I can think of is scanning using a GT1 knockoff, P.A. Soft, Bavarian Technic type tool to see what, if any, faults are being captured.

Performance Technic in Pleasanton gets good reviews, and they're open on Saturdays. Otherwise, Dorifto88 or Mfanatic325 can offer a good shop recommendation.

[yousefnjr]

Thanks for the replies. Unfortunately that diagram says its for an e89 z4 when I get home ill check the fuse box in the car for anything about a starter relay

I would definitely agree that this car seems to work only on its own terms, what a PITA this thing has been. If it wasn't so good once it's running I'd get rid of it... Reminds me of a girl I used to date

[XMetal]

The obvious...did you tried using your 2nd key (didn't see it mentioned in the post)?

[yousefnjr]

I only have the 1 key

[yousefnjr]

So I've been reading a lot of horror stories about folks buying the "lifetime warranty" starters from auto part stores, it doesn't appear to be an uncommon occurrence for them to be defective out of the box. When I took mine back to the store, they bench tested it and it passed, but that test doesn't have any load on the starter.

I found a place in Campbell called Autolectrics, they've been rebuilding starters for 20+ years. I'm going to take it in to them hopefully today and have them check it out, ill update when I found anything out

Aforementioned horror stories:
http://www.ripoffreport.com/o-reilly...roli-711ea.htm
http://67-72chevytrucks.com/vboard/s...d.php?t=322851

[elwesso]

I agree with that. It seems that O'Reilly's parts aren't very good, where Advance has some decent stuff...

Back in the days of yore, I worked for Delco Remy which makes all the starters and alternators for GM (and many other brands), and they do most or all of the rebuilds for Advance Auto.. While most of those alternators and starters get rebuild in Mexico, I know some of the guys at another facility in the US could rebuild any starter, generator, or alternator.

I also know from a friend of mine that worked at Advance for many years, that he saw very few of their alternators or starters get returned. He specifically commented to me how those products rarely came back, even under whatever warranty they're given.

[yousefnjr]

So I brought the starter in this afternoon and they tested it, they said its fine. I reinstalled it and of course it still won't work. I'm about to take a baseball bat to this POS car.

[yousefnjr]

I would also like to point out that the fuse card for this car is useless, it has little drawings for each fuse instead of words. What is this, pictionary?

[Finnegan]

I understand your frustration with this issue. But not many here have seen this same issue, so it's hard to offer advice, and it's not a common problem.

The fuses are quite frustrating, I agree. Here's an electrical diagram of the starter control circuit. Here's more on the immobilizer and starter. These two resources may or may not be helpful.

Since the car will start when pushed I think we can rule out the key/immobilizer.

Starter is good, so that can be ruled out.

That leaves the starter solenoid, the clutch switch, and various relays/modules.

I'd take another look at the clutch switch. Have you confirmed, outside of the click, that the circuit is actually opening/closing? Click may be giving a false indication.

The next is the starter solenoid, unless you've rule that out already.

You've done a good job in ruling out most of the obvious culprits. If the solenoid and starter switch don't pan out, maybe it's time to get someone Performance Technic or another good indie shop to look at it. Since you don't have diagnostic tools to read all of the errors, you're at a bit of a disadvantage in tracing the fault if it's indeed a module or relay.

[RobMCoupe]

Where are you located in Bay Area? I have PA Soft to scan for errors.

[thekurgan]

I"ve seen this exact issue creep up on the E46M3 boards. EXACT issue. I'm searching for the results and fix.

Here's one:

http://m3forum.net/m3forum/showthread.php?t=310634

The other I believe was related to the clutch pedal sensor or the key.

Looks like you swapped the starter ... mystery for sure man, hope you get it fixed.

[yousefnjr]

Thanks all

Fin, if I'm reading correctly, the second link you posted mentions that the relay for the starter is located within the EWS control unit:

"The key then sends data to the EWS3 control module. If this data is correct, the EWS3 enables the starter by way of a relay installed in the control module and additionally sends a coded start enable signal via a data link to the DME/DDE."

I've replaced the bum relay in the GM5 for door locks in the past, maybe this is similar in nature.

Haven't tested the clutch switch outside of hearing the click, I don't have the software

I made an appointment today at German Motor Specialists in Sunnyvale, I'm hoping they can do a better job at fixing this than I can. Ill update when I hear something.

[yousefnjr]

http://forums.bimmerforums.com/forum....php?t=1099965
This sounds just a little familiar...

I'm going to push back my appointment and see if I can bypass the relay in the EWS when I get home. It makes sense that this could be the cause, the DME is getting the OK to start, but the relay isn't firing the starter? Certainly explains the ability to push-start and nothing else

[Finnegan]

Here's another thread on ignition switch failures. Worth a look, as it's a Z4.

[yousefnjr]

Fin, you must be a fortune teller or something. I just got my car back from the shop, it was the ignition switch that was failing. I paid *considerably* more $$$ than the guys in that thread, but at least this thing is running again.

Thanks all

[Finnegan]

Originally Posted by yousefnjr

Fin, you must be a fortune teller or something. I just got my car back from the shop, it was the ignition switch that was failing. I paid *considerably* more $$$ than the guys in that thread, but at least this thing is running again.

Thanks all

Glad to hear it's fixed!

I'm guessing that the ignition was on (allowing push start), but whatever contact needs to be made to send juice to the starter wasn't working.

[noogi]

I had the same problem with my 03 x5; it was the key; eventually, the battery in the key dies..; so, use the spare key, or, replace the battery (there is a thread on how-to in xpost), or, go to dealer and get a new key..;