Help me please with my 1996 BMW Z3 Roadster

[Ron and a 1996 BMW Z3]

I have a cranking yet no start issue and I am in the process of figuring it out. I need help. Thanks

 

[colb]

First thing you need to do is plug a code reader scanner into it and see if it has set any fault codes which may well give you a clue to what has gone wrong. Could be a bad camshaft sensor or crankshaft sensor causing the no start or a problem with the EWS security system not allowing the car to start. Until you check for codes its just guesswork.

 

[Mr H]

 

[Ron and a 1996 BMW Z3]

Thank you for your response, colb. I found no codes. I have replaced spark plugs that had no electrode left (never seen ones this bad yet it ran great and idled perfectly!) I read that this could cause overheating of COP (coil on plug wire set) and/or the coil. I am replacing both soon. I have a crankshaft position sensor in hand (requires removing intake manifold), I cleaned up the throttle body (quite dirty), adjusted very loose throttle body cables to tighter then backed off the tension for some slack), I have a fuel pressure gauge hooked up; will test today by turning the ignition on. The car does crank over and the battery is good. It just wouldn't start one cold morning a couple of weeks ago. I haven't checked the fuel pump relay I see is found under the dash inside; hard to get to so gotta test for fuel at the rail first. I'm worried it could be the immobilizer chip in the ignition key as that I hear can be expensive. I was given a blank along with the keys when I bought the car 4 months ago. It was smogged and ran perfectly up until the no start condition a couple of weeks after a very cold night. The gas in the tank is pretty low so I am adding 5 gallons today. It does show some, however. I am new here and hope to meet many people who love this car. It may be the most fun car I ever owned outside a 1970 MGB I had in the mid 70's. I am a retired sub teacher after teaching for 30 years. EWS system? What is that, colb? (the immobilizer function?) Thanks to anyone and everyone for your help and concern. I am so frustrated right now.

 

[Ron and a 1996 BMW Z3]

Thanks, Mr. H!

 

[Ron and a 1996 BMW Z3]

Thanks, Mr. H!

Would you happen to know anything about an IAC (idle air control valve) buzzing while the ignition is on, not running? I had never heard anything like this and finally found the buzzing I was hearing. I put my hand on the IAC and it stopped buzzing. WTH is this? Thanks. It's not an expensive part so...

 

[Shelly]

 

[colb]

Idle control valve buzzing noise usually down to it being ditrty and in need of a clean. Take it off and sray carb cleaner in it and give it a good shake to agitate the dirt thats built up in there, dry it out with some compressed air if you have a compressor or just let it drain before refitting it.
The EWS system is indeed the cars security module that controls the locking/unlocking and reads the transponder in your key when its put into the ignition. There are two distinct systems in a key, one is the lock unlock system that operates with the buttons on the key, this is contained inside the fob on a small printed circuit board on which is a rechargable button battery that powers that part of the key. The battery gets charged by the car when its active in the ignition and engine running. Bear in mind these batteries are getting ancient now and nothing lasts forever, it may have lost the ability to store a charge. Resting the key overnight or longer on a domestic toothbrush charger will surprisingly charge the battery. Give it a try and see if it comes to life. The key if charged may need resyncing to the car to get the lock/unlocking buttons to work correctly. Threads on here to show you how if you have a search.
The second system within the key fob is the transponder chip that contains the cars identity that will be read by the EWS module when the key is inserted in the ignition, it will look at the info on the chip to verify the key belongs to the car and a second code called a rolling code that the car gave to the key the last time it was used in the car. If these match it will release the starter motor and allow the car to start.
The transponder has no power supply in the fob, it works by BMW Black Magic and a small aerial that is contained in the plastic surround around the ignition key switch.
EWS module is located behind the outer footwell side panel on a right hand drive its on the right hand side, not sure if left hand drive cars will be the same, maybe look on the left if its not on the right. Module is a small white oblong box held in by one nut.
If you take it out it has one multi pin connector. Nothing to really see if you take it apart other than a printed circuit board, if you spot any blown componants on it or maybe water damage/corrossion then maybe look for a known good replacement. Replacements need coding to the car using software such as NCS Expert. When sourcing a replacement it must be the same part number as the one it is replacing.

 

[Ron and a 1996 BMW Z3]

Idle control valve buzzing noise usually down to it being ditrty and in need of a clean. Take it off and sray carb cleaner in it and give it a good shake to agitate the dirt thats built up in there, dry it out with some compressed air if you have a compressor or just let it drain before refitting it.
The EWS system is indeed the cars security module that controls the locking/unlocking and reads the transponder in your key when its put into the ignition. There are two distinct systems in a key, one is the lock unlock system that operates with the buttons on the key, this is contained inside the fob on a small printed circuit board on which is a rechargable button battery that powers that part of the key. The battery gets charged by the car when its active in the ignition and engine running. Bear in mind these batteries are getting ancient now and nothing lasts forever, it may have lost the ability to store a charge. Resting the key overnight or longer on a domestic toothbrush charger will surprisingly charge the battery. Give it a try and see if it comes to life. The key if charged may need resyncing to the car to get the lock/unlocking buttons to work correctly. Threads on here to show you how if you have a search.
The second system within the key fob is the transponder chip that contains the cars identity that will be read by the EWS module when the key is inserted in the ignition, it will look at the info on the chip to verify the key belongs to the car and a second code called a rolling code that the car gave to the key the last time it was used in the car. If these match it will release the starter motor and allow the car to start.
The transponder has no power supply in the fob, it works by BMW Black Magic and a small aerial that is contained in the plastic surround around the ignition key switch.
EWS module is located behind the outer footwell side panel on a right hand drive its on the right hand side, not sure if left hand drive cars will be the same, maybe look on the left if its not on the right. Module is a small white oblong box held in by one nut.
If you take it out it has one multi pin connector. Nothing to really see if you take it apart other than a printed circuit board, if you spot any blown componants on it or maybe water damage/corrossion then maybe look for a known good replacement. Replacements need coding to the car using software such as NCS Expert. When sourcing a replacement it must be the same part number as the one it is replacing.

Thank you very much for taking the time to help me. I really appreciate it. I did indeed clean it up and the buzzing went away and I cleaned up the throttle body (quite dirty) and MAF sensor (looked pretty clean) I am cleaning every connection I can see. I don't have any help here yet; a neighbor maybe but I really do not even know him yet. I will look for that EWS module. I really do appreciate that you took the time to message me. What year and model is your Z3? South Wales, wow! I woukld love to see these places; never been to Europe and cannot afford it or foresee that ever happening.

 

[colb]

No problems, we are all on here to help each other where we can no matter where in the world, members from all over the Globe.
Cleaning the idle control valve out has probably sorted that buzzing you had and cleaning the throttle body will have been a good move. If the Maf was faulty I would not expect it to stop the car from starting, they do in my experience either work or fail altogether. If you disconnect the electrical plug from the Maf the car will revert to default settings in the engine computer (DME). You could try that and see if it starts. Next check would be to pull a spark plug and ground it on the engine and then crank the engine on the key, see if you have a spark at the plug. If you have that would indicate the EWS is allowing it to crank. Once you have a spark next step would be to check for fuel, can you hear the fuel pump run when you switch on? As its fuel injection you could test for fuel pressure at the fuel rail but you need a fuel pressure guage to do that, connection valve to do that is on the fuel rail. Shame you didn't find any codes set it might have given us a better clue to whats gone wrong.
Back to the Maf if you clean it use only Maf cleaner and dont touch the actual sensor componants, tried cleaning mine but it killed it completly. New oem Maf sorted mine.
If you do end up replacing any sensors always use oem brands never cheap pattern ebay parts they rarely work well or work at all, been there and done that myself. Always go for Bosch or Seimens oem brands.
My car(s) are 1999 Z3 1.9 and a 2003 Z4 2.5, update us with your model, especially the engine size and year.

 

[bombur]

Im from South Wales also and I can tell you one thing...Santa Cruz has appeal!

 

[Ron and a 1996 BMW Z3]

No problems, we are all on here to help each other where we can no matter where in the world, members from all over the Globe.
Cleaning the idle control valve out has probably sorted that buzzing you had and cleaning the throttle body will have been a good move. If the Maf was faulty I would not expect it to stop the car from starting, they do in my experience either work or fail altogether. If you disconnect the electrical plug from the Maf the car will revert to default settings in the engine computer (DME). You could try that and see if it starts. Next check would be to pull a spark plug and ground it on the engine and then crank the engine on the key, see if you have a spark at the plug. If you have that would indicate the EWS is allowing it to crank. Once you have a spark next step would be to check for fuel, can you hear the fuel pump run when you switch on? As its fuel injection you could test for fuel pressure at the fuel rail but you need a fuel pressure guage to do that, connection valve to do that is on the fuel rail. Shame you didn't find any codes set it might have given us a better clue to whats gone wrong.
Back to the Maf if you clean it use only Maf cleaner and dont touch the actual sensor componants, tried cleaning mine but it killed it completly. New oem Maf sorted mine.
If you do end up replacing any sensors always use oem brands never cheap pattern ebay parts they rarely work well or work at all, been there and done that myself. Always go for Bosch or Seimens oem brands.
My car(s) are 1999 Z3 1.9 and a 2003 Z4 2.5, update us with your model, especially the engine size and year.

Thank you so much. I have always wanted to be on a site where people could help each other and hopefully, there are enough members who participate that this will be helpful. You certainly have been and I appreciate it. I do have a fuel pressure gauge hooked up to the rail but no one to crank it over for me. It does crank over. Mine is a 1996 BMW Z3 1.9 liter. I did, of course, use MAF sensor spray; thanks for the heads up. I have a new coil and new spark plug wire set on the way. Though the car was running perfectly up til no start condition the spark plugs were fried to the nub, no electrode left! I had never seen any so bad! Because of the far too large gap may be the coil overheated and fried. I am just now learning how to use my multimeter. I did take an auto electrical class but I was working full-time teaching and I had no time to study. I'd like to retake the class! Some say "don't throw parts at it" but I feel that it's not that costly and I want to know parts are new, not 10-25 years old! I have a camshaft position sensor to put in if need be and a crankshaft position sensor, too. I haven't put them in yet. The info I have on my manual and that I find online is so confusing as it doesn't reflect what I have. (ex. manual and net showed fuel pump relay to be under dash under the steering column. I checked; no relays down there. I found it in the DME box. I am cleaning up prongs on the relays and just learned how to test them on youtube. I have a new fuel filter to put on soon. The gas tank is low but the reading is good enough it has always started before. It did not start one cold morning two weeks ago. I have some HEET to put in to solve any moisture/water in the tank issue and I am putting 5 gallons in today. Thank you again so much for your time and consideration. I have been charging the battery (only 4 months old) and it's dropping to 65% after sitting a few hours. I could have a parasitic draw somewhere and I am not versed in finding that; I have spent at least 30-40 hours watching youtube vids so I am learning so much during this downtime. I'm waiting on a new plug wire set as a seller actually sent me a crankshaft position sensor instead; completely wrong part! (off eBay) Ive reordered a set from a different seller. Thanks again. Ron

 

[colb]

Ok, 1996 1.9 so its got a M44 Engine, my 1999 model has the M43 engine they changed over in late 1999.
What code reader have you been using its strange that it hasn't thrown any codes up, if it was camshaft or crankshaft sensors they should trigger codes. Maf's dont always set codes, they seem to work or not at all or underperform causing fuel trim issues when the engines are running. Being an early pre facelift model not all code readers will work, probably best to try BMW INPA on a laptop via the 20pin engine bay diagnostic socket. If you have replacement sensors to hand, fit them and see if that makes any difference whilst you await the coils and plug leads.

 

[Ron and a 1996 BMW Z3]

Thanks, the code reader is a fairly new Foxwell. It makes me think in the end I am gonna find something so easy was the problem all along. I have a Chilton manual but I am frustrated by things that just don't accurately tell where things are. I have a Haynes manual on the way so I will have both. My retirement pension is quite low so I do not have means to take it in somewhere yet. I am getting readu to go outside and poke around some more. I definitely need the neighbot to at least come over so I can check for spark and fuel. I'm shooting in the dark in many ways but I am learning the car and the condition of things, too. RU familiar with where I live in Santa Cruz, California?

 

[Ron and a 1996 BMW Z3]

Ok, 1996 1.9 so its got a M44 Engine, my 1999 model has the M43 engine they changed over in late 1999.
What code reader have you been using its strange that it hasn't thrown any codes up, if it was camshaft or crankshaft sensors they should trigger codes. Maf's dont always set codes, they seem to work or not at all or underperform causing fuel trim issues when the engines are running. Being an early pre facelift model not all code readers will work, probably best to try BMW INPA on a laptop via the 20pin engine bay diagnostic socket. If you have replacement sensors to hand, fit them and see if that makes any difference whilst you await the coils and plug leads.

Colb, I just went out and my battery shows a 59% charge; maybe a bad battery but I did a load test yesterday and it showed OK. For sure, maybe I have a parasitic draw. I remember when I bought it the guy said he would put the battery on a trickle charger overnight. That battery was old and gone so I replaced it. I haven't had any issues in 4 months, however so must be something else. I have put on 5,000 miles since I owned it. Oh, I do see that it appears I can attach a photo here; that would be great! With the DME box open I am seeing a connector just lying there and a spot that appears it would have something in it! I may be completely missing something! I'll take a pic and see if I can upload it here. That would be incredibly useful.

 

[Ron and a 1996 BMW Z3]

Took a pic and tried to upload...says "the file is too large to process". Darn it.

 

[colb]

Try and resize the photo using a photo editing program that should do it to enable posting it.
That cable might be for a module that wasn't fitted to your car in the factory as they used the same harness for all, only connected if the car had certain options chosen by the buyer. If the car ran ok before you found that connector I would ignore it.
I would have thought the Foxwell would have read codes ok but the early models used pre OBD2 and can be problematic when it comes to code reading often needing BMW INPA on a laptop with an old style serial port as they don't like usb connections.
As to battery draw check out the Youtubes on testing for it, This guy is an expert on Auto Electrics Pine Hollow Auto Diagnostics.
Like you but opposite never been to the USA apart from calling in to Puerto Rico on a Cruise Ship, looks like you live in a nice place by the coast, about an hour away from San Fransisco. I may get there one day.

 

[colb]

Finding where things are located can be a problem, best advice is to take a look at the diagrams for your car on the Realoem parts site, its free and if you put the last 7 letters and digits of your Vin number in on the search page it will return the parts index for your actual car with clear diagrams that pinpoint where they are fitted usually. Link to site here

RealOEM.com - Select Your BMW Model

RealOEM.com BMW Parts website. This site can be used to look up BMW part numbers and approximate part prices. The Parts are grouped into diagrams and diagrams are grouped into categories and subcategories

www.realoem.com

 

[Ron and a 1996 BMW Z3]

Finding where things are located can be a problem, best advice is to take a look at the diagrams for your car on the Realoem parts site, it's free and if you put the last 7 letters and digits of your Vin number in on the search page it will return the parts index for your actual car with clear diagrams that pinpoint where they are fitted usually. Link to site here

RealOEM.com - Select Your BMW Model

RealOEM.com BMW Parts website. This site can be used to look up BMW part numbers and approximate part prices. The Parts are grouped into diagrams and diagrams are grouped into categories and subcategories

www.realoem.com

Thanks, I will try that, too. I am finding something that appears to be missing inside the DME box and it has two female end connectors just hanging there. I'm wondering if this is an ABS module (have an ABS light on) or an Airbag module of some sort of an actual ECM or it could be an immobilizer module of some sort. Wow, is this ever complicated and confusing? Though I have too many automotive tech classes at a community college I need more!

 

[colb]

Won't be the airbag module that lives under the centre console in front of the gearstick.
ABS control unit will be part of the actual ABS unit to the right of the engine bay as you look into the engine bay.
The missing module(s) that would use those loose connectors may be headlamp washer module, has yours got that?
Now you mention you have an ABS light lit that makes me more suspicious of your Foxwell scanner, that light would set a code and if its not finding it I would believe the Foxwell can't read your car. I think you are going to need BMW Inpa on a laptop with an old serial port and suitable cable to connect the INPA interface to.