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#1. RE: [E36M3] buying new ignition coils - thoughts? - from Andrew Kalman
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Date: Mon, 20 Nov 2006 21:06:18 -0800 From: Andrew Kalman <aek@pumpkininc.com> Subject: RE: [E36M3] buying new ignition coils - thoughts? From another EE, it is certainly possible for a bad coil to take down an ECU. There are all sort of overvoltage and overcurrent failure modes that can bring down upstream electronics. It becomes too expensive to try to cover every base, and the odds of the "protection" components going bad probably outweighs the rare coil-kills-ECU failure. For example, if a low-voltage coil driver inside the ECU fails (perhaps because of back EMF from the coil itself, or a shorted harness or shorted coil, or maybe just an internal failiure), the ECU's output pin(s) to the coil driver are at its mercy. If it momentarily presented a large over- or under-voltage with sufficient power (i.e. current) to the ECU, or as a massive current sink or source, it could latch up the CPU, even destructively. That said, I have seen my father-in-laws Ford F250 blow three coils, and our Mazda MPVG blow all six, but the ECUs are all still fine. My '95 LWT still has its original coils. I'm not too worried about it. I suspect that if the coils were opto-isolated then there would be near-zero probability for this happening. :) ______________________________________ Andrew E. Kalman, Ph.D. aek@pumpkininc.com >Date: Mon, 20 Nov 2006 23:37:51 -0500 >From: "Tom Tice" <tetice@triad.rr.com> >Subject: RE: [E36M3] buying new ignition coils - thoughts? > >Hey James, > >From one EE to another, do you have any solid information to suggest this >was more than just a coincidence? I've heard this before and it just >doesn't seem logical to me - perhaps I'm giving the engineers at Bosch or >Siemens way too much credit but I would think it ludicrous to design a >system where one relatively inexpensive component's failure can take out a >much more complex and expensive component. I've personally had some >dealings with BMW's quality department and they absolutely will not allow >anything resembling reliability this questionable - at least with our >components. > >If anyone else has hard evidence that this is a cause and effect situation, >I'd like to hear it. I'm currently running all original coils in my '93 325 >JP car with 130K miles on them - I had no intention of replacing them until >they fail. > >If there is not hard evidence, perhaps a statistical approach would help. > >Anybody else have a coil failure without frying their CPU? > >I know it could be model or CPU specific but I had one go bad in my '02 X5 - >replaced it with no other issues. I drove it for a few days with it >behaving intermittently. It's amazing how much smoother 6 cylinders are >than 7 (when it's designed for 8). > >Tom Tice >'98 M3/4 >'93 325iS JP 110 >'02 X5 4.4 >'02 325iT/5 > > > > > > > > >-----Original Message----- >From: James Clay [mailto:james@bimmerworld.com] >Sent: Monday, November 20, 2006 2:54 PM >To: E36M3 >Subject: Re: [E36M3] buying new ignition coils - thoughts? > >Date: Mon, 20 Nov 2006 14:45:01 -0500 >From: "James Clay" <james@bimmerworld.com> >Subject: Re: [E36M3] buying new ignition coils - thoughts? > >Replace all 6 at once! I just fried my computer this fall with a bad coil. >They have a lifespan. > > > >James Clay >http://www.bimmerworld.com >http://www.bimmerworldracing.com >http://www.powerflexusa.com >Race Proven BMW Performance >877.639.9648 > --
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#2. Re: [E36M3] How much is my old S50 worth?? - from jeff.conner@yahoo.com
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Date: Mon, 20 Nov 2006 21:39:02 -0800 (PST) From: jeff.conner@yahoo.com Subject: Re: [E36M3] How much is my old S50 worth?? Don't listen to these guys, they don't know what they're talking about. I've got $225 for you and I'll even throw in the paypal sellers fee! -jef From: David Thomas <dave@sasdatalink.com> On Monday 20 November 2006 8:24 pm, Mike VanAmburgh wrote: > Date: Mon, 20 Nov 2006 22:19:12 -0600 > From: "Mike VanAmburgh" <mvanamburgh@charter.net> > Subject: Re: [E36M3] How much is my old S50 worth?? > > Not a penny over $100.. Do you have PayPal? ;-) Nah...at least $110. So...do you have PayPal? lol Dave ____________________________________________________________________________________ Sponsored Link Mortgage rates near 39yr lows. $420k for $1,399/mo. Calculate new payment! www.LowerMyBills.com/lre
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#3. RE: [E36M3] buying new ignition coils - thoughts? - from Tom Tice
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Date: Tue, 21 Nov 2006 00:42:32 -0500 From: "Tom Tice" <tetice@triad.rr.com> Subject: RE: [E36M3] buying new ignition coils - thoughts? I agree it is possible and there are many mechanisms as you point out. However, the automakers (at least these days) require electronics manufacturers to perform extensive FMAs (Failure Mode Analysis) to predict (and design in protection for) things such as this and to reduce the likelihood of them occurring to very small fractions of a percent. Obviously in spite of the best engineering analysis, things can still get missed. This is a great list, sharing all sorts of knowledge and valuable information. In this case, I'm just interested in making sure there is more to go on than just a coincidence. James, no offense to you - you share tons of valuable information and I've certainly benefited from lots of it. Related to this, I've also seen discussions of CAI air filter oil causing MAF sensors to fail. Within 1 week of the installation of a CAI on my 325iS, the MAF senor bit the dust. I'm not jumping on that bandwagon because I think it was pure coincidence - it's time was just up after 125K miles. No problems with the replacement (knock on wood) sensor after additional filter cleaning and oilings. Tom Tice -----Original Message----- From: Andrew Kalman [mailto:aek@pumpkininc.com] Sent: Tuesday, November 21, 2006 12:06 AM To: Tom Tice Cc: e36m3@bmw-m.net Subject: RE: [E36M3] buying new ignition coils - thoughts? From another EE, it is certainly possible for a bad coil to take down an ECU. There are all sort of overvoltage and overcurrent failure modes that can bring down upstream electronics. It becomes too expensive to try to cover every base, and the odds of the "protection" components going bad probably outweighs the rare coil-kills-ECU failure. For example, if a low-voltage coil driver inside the ECU fails (perhaps because of back EMF from the coil itself, or a shorted harness or shorted coil, or maybe just an internal failiure), the ECU's output pin(s) to the coil driver are at its mercy. If it momentarily presented a large over- or under-voltage with sufficient power (i.e. current) to the ECU, or as a massive current sink or source, it could latch up the CPU, even destructively. That said, I have seen my father-in-laws Ford F250 blow three coils, and our Mazda MPVG blow all six, but the ECUs are all still fine. My '95 LWT still has its original coils. I'm not too worried about it. I suspect that if the coils were opto-isolated then there would be near-zero probability for this happening. :) ______________________________________ Andrew E. Kalman, Ph.D. aek@pumpkininc.com >Date: Mon, 20 Nov 2006 23:37:51 -0500 >From: "Tom Tice" <tetice@triad.rr.com> >Subject: RE: [E36M3] buying new ignition coils - thoughts? > >Hey James, > >From one EE to another, do you have any solid information to suggest this >was more than just a coincidence? I've heard this before and it just >doesn't seem logical to me - perhaps I'm giving the engineers at Bosch or >Siemens way too much credit but I would think it ludicrous to design a >system where one relatively inexpensive component's failure can take out a >much more complex and expensive component. I've personally had some >dealings with BMW's quality department and they absolutely will not allow >anything resembling reliability this questionable - at least with our >components. > >If anyone else has hard evidence that this is a cause and effect situation, >I'd like to hear it. I'm currently running all original coils in my '93 325 >JP car with 130K miles on them - I had no intention of replacing them until >they fail. > >If there is not hard evidence, perhaps a statistical approach would help. > >Anybody else have a coil failure without frying their CPU? > >I know it could be model or CPU specific but I had one go bad in my '02 X5 - >replaced it with no other issues. I drove it for a few days with it >behaving intermittently. It's amazing how much smoother 6 cylinders are >than 7 (when it's designed for 8). > >Tom Tice >'98 M3/4 >'93 325iS JP 110 >'02 X5 4.4 >'02 325iT/5 > > > > > > > > >-----Original Message----- >From: James Clay [mailto:james@bimmerworld.com] >Sent: Monday, November 20, 2006 2:54 PM >To: E36M3 >Subject: Re: [E36M3] buying new ignition coils - thoughts? > >Date: Mon, 20 Nov 2006 14:45:01 -0500 >From: "James Clay" <james@bimmerworld.com> >Subject: Re: [E36M3] buying new ignition coils - thoughts? > >Replace all 6 at once! I just fried my computer this fall with a bad coil. >They have a lifespan. > > > >James Clay >http://www.bimmerworld.com >http://www.bimmerworldracing.com >http://www.powerflexusa.com >Race Proven BMW Performance >877.639.9648 > --
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#4. RE:Re: [E36M3] Carfax help - from George and Clare Thielen
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Date: Tue, 21 Nov 2006 07:55:40 -0500 From: "George and Clare Thielen" <gcthielen@earthlink.net> Subject: RE:Re: [E36M3] Carfax help Tucker, You're right about this board being a great resource. I sold my M3 sedan months ago to buy a ZHP E46 but still love this list. However, the prospect of you (or any other list member) purchasing a car at auction with confidence due to a clean Carfax is somewhat disconcerting to me. Don't misunderstand, Carfax is a great tool, but has serious reporting limitations and should only be used as a first step in a thorough professional inspection. Even Carfax agrees. Just last week, I inspected a 60K 2002 Subaru, one owner, one dealer serviced since new, new car trade-in, being sold by the same dealer on their lot with a clean Carfax....guess what? In August 2003 the service records said the following: Cust states car won't start: car in flood, water in engine, replace engine, replace ECU, replace carpeting, install charcoal canister to absorb odors.....get the picture? Be careful out there and try to take an expert to the auction with you...it's cheap insurance. Good luck! George Thielen Mobile Used Car Inspections Dayton's first and only used car inspection service... "where the inspector comes to you!" www.mobileinspections.com
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#5. List cancellation - from Craig Perrin
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Date: Tue, 21 Nov 2006 08:04:49 -0500 From: Craig Perrin <cperrin@tampabay.rr.com> Subject: List cancellation Suzie, Please delete my name from the list. After 5 years of enjoyable daily reading, I have sold my E36 M3. In its place -- an E46 M3! Thanks for maintaining this very useful service. Craig Perrin
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#6. off idle response - from Mike DePolo
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Date: Tue, 21 Nov 2006 09:37:55 -0500 From: "Mike DePolo" <smiked1@gmail.com> Subject: off idle response Hello everybody. This is my first post. I just bought a 95 M3 after a long search for the right car. I've owned an e30 M3 for a long time that I've now designated as a fun/track car. It's in great shape, so it will now reside in the garage under a cover most of the time. The e36 will be my daily driver. I'm very happy with the e36, but one thing that bothers me is the way the idle drops when while I'm releasing the clutch pedal. On my e30 I can slowly release the clutch and let the torque start to pull me forward before giving it much throttle. The e36 seems to start to pull, then the idle will quickly drop. At this point it will either stall, or if begin to disengage the clutch to prevent the stall, the engines bucks and quickly surges to around 1500-2000 rpm. I can drive the car smoothly, but I have to rev it more than I like and slip the clutch. Is this normal behavior? Maybe a characteristic of the dual mass flywheel? Could this be an ICV problem? The car idles very smoothly and runs great otherwise. I can learn to live with it, but I've never had to slip the clutch this much in any car I've ever owned. I noticed this same behavior in the cars I test drove, so maybe this is a normal condition. Thanks. Mike
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#7. Re: [E36M3] buying new ignition coils - thoughts? - from Carlos Lopez
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Date: Tue, 21 Nov 2006 10:02:32 -0500 From: "Carlos Lopez" <clopez98m3@gmail.com> Subject: Re: [E36M3] buying new ignition coils - thoughts? On 11/21/06, Tom Tice <tetice@triad.rr.com> wrote: > > >Related to this, I've also seen discussions of CAI air filter oil causing > >MAF sensors to fail. Within 1 week of the installation of a CAI on my > >325iS, the MAF senor bit the dust. I'm not jumping on that bandwagon > >because I think it was pure coincidence - it's time was just up after > 125K > >miles. No problems with the replacement (knock on wood) sensor after > >additional filter cleaning and oilings. What type of filter? I thought for sure I would kill the MAF/HFM whatever it is in my '98 M3 after I cleaned and oiled my ITG filter (used too much oil in my opinion). Last minute thing right before a track event so I just went with it. Finally a month later when I had time to inspect the MAF it is perfectly clean, no oil went downstream AFAIK. I inspected all the connections, boots, throttle body, etc. Now on the killing the DME thing (CPUs?? ;-) ), a close friend with an E30 M3 had a couple of resistors fried inside the DME and it was caused by a bad idle control valve. Tried another DME and that one got fried also. Finally replaced the ICV and that was the end of the fried resistors. Luckily someone had info on which resistors to purchase from da Shack and a friend with mad soldering skillz was able to fix both boards. Symptom of the fried resistors was a hunting idle. Fixed after the new resistors were soldered in. So these BMW guys suck at FMAs. ;-) We actually do FTAs here (fault tree) because our VP of Engineering came from Honda and they are big on those things. Carlos. :-) (automotive ind. sucks)
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#8. Re: [E36M3] off idle response - from Rex Tener
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Date: Tue, 21 Nov 2006 09:47:34 -0700 From: Rex Tener <rex_tener@yahoo.com> Subject: Re: [E36M3] off idle response At 07:44 AM 11/21/2006, Mike DePolo wrote: >The e36 seems to start to pull, then the idle will >quickly drop. At this point it will either stall, or if begin to disengage >the clutch to prevent the stall, the engines bucks and quickly surges to >around 1500-2000 rpm. Once your car is going more than 1.4 MPH the idle circuit is no longer active and will cause this behavior. About ten years ago Jim Conforti posted this: <http://www.unofficialbmw.com/e36/engine/e36_m3_idle_surge.html> It sounds like your exact situation, but engaging the clutch instead of disengaging. >The car idles very smoothly and runs great otherwise. I can learn to live with >it, but I've never had to slip the clutch this much in any car I've ever >owned. I noticed this same behavior in the cars I test drove, so maybe this >is a normal condition. One of the tricks I learned from one of my autocross friends, is to give the car a little throttle and then release it, and as the RPM's fall, start to engage the clutch and then give it a little a throttle after the car is moving. Rex
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#9. Euro Part Purchases - from Burgess, Kim L
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Date: Tue, 21 Nov 2006 11:50:33 -0800 From: "Burgess, Kim L" <kim.l.burgess@boeing.com> Subject: Euro Part Purchases Group - Where have we been going to source Euro parts - Euro Diesel Fan Blade? TIA KLBurgess
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#10. RE: [E36M3] buying new ignition coils - thoughts? - from James Clay
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Date: Tue, 21 Nov 2006 14:51:24 -0500 From: "James Clay" <james@bimmerworld.com> Subject: RE: [E36M3] buying new ignition coils - thoughts? I have long since abandoned my EE studies... I assume that there is more than one way a coil can fail. They should have a power, ground, and signal wire effectively. I think the failure that destroys the computer is when it creates a direct short, which feeds back to the computer. I would assume this may mean the short of the signal wire, which would be going to the igniter contained in the ECU, which can likely wreck havoc. I would assume the other type of failure is when contact is no longer made with one of the other 3 wires - the opposite of the short situation. Either way, it seems that they have somewhat of a lifespan and when one dies, the others are likely to be within a similar lifespan window. James Clay http://www.bimmerworld.com http://www.bimmerworldracing.com http://www.powerflexusa.com Race Proven BMW Performance 877.639.9648 -----Original Message----- From: Tom Tice [mailto:tetice@triad.rr.com] Sent: Monday, November 20, 2006 11:38 PM To: 'James Clay'; 'E36M3' Subject: RE: [E36M3] buying new ignition coils - thoughts? Hey James, >From one EE to another, do you have any solid information to suggest this was more than just a coincidence?