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I've been on a forum deep dive for the past couple of weeks due to a crank, no start condition on my '93 325i. I had this car parked for the past couple of years just turning it on once every few months. On my last attempt a couple of weeks ago, it started cranking on not turning over. I started with fresh fuel and filter, then a new fuel pump (was not even engaging at all when jumping the relay manually... now I can hear the pump engage, still no start) I've tested my main and fuel relays by swapping with known good relays from another e36, nothing. I am currently not getting any spark. I am now focusing my efforts on the crankshaft Position sensor... but here's where it gets weird. The existing CPS is measuring at 555ohms. This should be within spec, but still no start. I went ahead and figured, what the hell, let me get another sensor just to see. I purchased a Hella branded CPS (PN#6PU 009 110-541) the manufacturer's specs indicated that this sensor is supposed to be 540ohm, but my first one measured 934 ohms, and I returned it just in case it was faulty, well, the replacement measures 927ohms. What are the odds that these are both out of spec? I did use multiple multimeters and verified with some resistors BTW. I am puzzled as to why these would measure so differently. Has anyone experienced this? I'm still running down the list testing other potential causes, but I can't quite check this off my list
Balogne Cajones
New age magnetic sensors read out to that.
It sounds like your ews is triggered. Maybe battery went low and triggered it, maybe the locks went wierd on you with low voltage.
Try locking and unlocking the door with the key a few times with a fully charged battery.
Then if that doesn't work, check the door latch switch/zke on the door latch assembly and make sure it's on all the way.
If none of that works there's a pin on the 18 pin socket in the passenger footwear that has a security lock/unlock message you can jump, and would bypass any ews security lock measures.
If that doesn't work, your gonna need a key.
Member
Thanks for taking the time to reply! Let me start by saying thank you regarding the sensor ohms reading. I could not find that info anywhere. So I'm assuming that with newer magnetic sensors the only time to worry is when its reading MOhms or something crazy then? As far as EWS, I did not even consider this a possibility. I wasn't even aware of its existence in a '93 You sent me down a rabbit hole reading up on EWS. I've owned this car for over 25 years and I'm still learning something new. Thanks! I hope to have some time this week to continue troubleshooting.
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Being in Florida is the car garaged? If not the DME can get flooded due to clogged cowl drains (poor design) and heavy rain. The circuit board on the DME does not have a protective coating and will grow white oxide that will short out components. The DME can be taken apart and cleaned with a product called Deoxit 5% and scrubbed with an old toothbrush. Hose it all down with the deoxit and scrub everything, repeat. Do not reinstall until 100% dry, the deoxit will leave a protective film. If you find corrosion or not sure take a pic and post it here.
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The car was stored covered outside for a while (about a year) and then garaged again. I did take a look at the DME and it was bone dry, no leaves either. I didn't open it up to look at the components. That will definitely be on the todo list as well. Thanks for the Deoxit tip. I'll post pics once I start working on it again!
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Yeah you have to open it up, the compartment being dry doesn't mean anything, that will dry out rather quickly the damage could have started long ago. You have to look at both sides of the circuit board.
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Balogne Cajones
Yea. A short lookup had bmw installing "drive away protection" on cars produced from 9/93 to 12/93. From 1/94 was ews1.
If you have a "drive away protection" 93 model car, the system is the door locks, the obc, the general module and the dme. Technically "drive away protection" is "ews" and seperate from ews1 and ews11.
Member
Would it throw a wrench in the theory if I mentioned that my car's production date is 2/93?
Balogne Cajones
Yup. Sure would.
Balogne Cajones
Check the cam sensor as well? The crank sensor detects engine speed, the cam sensor detects which stroke the engine is on in most older engine management systems. Maybe bad cam sensor is causing no spark.
Member
Sorry for the crazy delay, I finally had time this morning to test out a few things. I can confirm that the car does have spark, I was testing wrong, and finally just the the spark plug to a ground point and saw the arcing... So we are now back to fuel instead of spark. I did open up the DME and that looks insanely clean. Not one blemish (that I can see). I've attached in case the DME is still relevant https://imgur.com/a/4qeCvrF
So, since this car has a build date of 2/93, there should be no immobilizer (Confirmed with INPA which shows up as no immobilizer when I connected, also no codes stored either). I focused my attention on Fuel again. I first changed out the fuel filter and then connected a fuel pressure gauge and proceed to do the same tests as in this video: https://www.youtube.com/watch?v=zRrKEzPKpKs&t=557s In this video around the 8 minute mark he mentions testing possibly leaking injectors or issues with fuel pressure regulator. I did clamp the input side just like he did and noticed that within a couple of minutes I drop close to 15 PSI so there is something funny happening with the fuel. I can't se any obvious leaks in the hoses, so It could be injector or fuel pressure regulator. I am not sure where to go next. I am considering changing out the rail, regulator and injectors with a used set, but any other ideas are appreciated. Thanks!
Member
Nice job on the dme pics. Yeah your dme is super clean it may have been coated by a previous owner. I only see one suspect solder point that is not good IMO but it may be fine, its up to you if you have good soldering skills and a hot iron to do a quick fix. Note I cannot see the solder point above the one I point to as well as the long line of solder joints under the green protector.
Concerning your crank sensor, I would go to the store with a multimeter and buy one that meets factory spec and would return the one way out of spec and tell them that its not an oem sensor and you want a refund.1TbuWgE.jpg
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Wanted to respond to this thread as I was finally able to take another stab at diagnosing the car. I ending up keeping my original Crankshaft sensor that was showing 555 OHMS. I returned the rest. I ended up tracing the fuel supply and noticed that the fuel return line was completely dry. Fuel was definitely making its way to the rail, but nothing out from it. I bought a new fuel pressure regulator and while I was at it I bought an injector rebuild kit. Once I put both of those in, the car fired up immediately! Sounded like a diesel for a bit, but I was extremely happy though. Thank you spyderg0d and Eric93se for your suggestions. You have both helped me learn how to tackle the fuel/spark diagnosis procedure and I know that if something like this happens in either of my E36's I will have a plan of attack going forward. Thank you for sharing your knowledge.
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