1999 BMW Z3 coupe won't start! HELP!

[riverrat0341]

1999 BMW Z3 coupe with 2.8L (M52 motor) with Siemans 42.1 DME

Ok, I got the car cheap b/c no one could fix it. I'm pretty sure that the car was jumped off with the battery cables backward and reaped havoc. It burned ground wire in half. Fried the computer, Fuel pump, and a relay, all been fixed/replaced. New DME installed and set up by BMW of montgomery. Here is a list of what I've checked and then the problem I'm stuck at without knowledge or prints of the actual DME. The engine will turn over but won't bust off. No fuel through injectors, no fire from plugs, no SEL.

Good PSI on fuel rail
Good compression
Checked hot and ground to DME.
Diagnostics scan shows no faults.
Crank position sensor reads good out of car. - Tried 3 different sensors, all good on bench. Put 12V in get 12V back on signal wire. Checked signal wire going into DME on o scope and it is a 6V square wave. Is this right?
Camshaft position sensor reads good IN the car. - checked signal with analog meter. Have fluctuation.

Ok, I checked the voltage on the pins of the plug from hot to ground where it plugs into the crank sensor to make sure I didn't have a short or somthing, haven't checked continuity of signal yet. It's my understanding that the only thing the car uses to start is those 2 sensor and I understand it gets a ground from the DME to fire injectors and coils. These are holding at 6v as well. I have amp clamp, DMM (both Fluke), O-scope, and 12V pwr supply. If I had prints of the DME I can read and do the math on it all but would rather not if I can help it. Do you have any idea why it would be 6 instead of 12??? Is there something else that could cause this?

[mmyohe]

IS the EWS aligned to the new DME?

[riverrat0341]

ok, think I'm on the right track and sounds like you guys are too. The 99Z3 was a mix breed in that area. It has an EWSIII and a specific program. The car was taken to a dealership and the computer was bad and it had burnt in half ground wires. Like 5 of them. So they fixed that and installed a new, VIN coded dme in it and linked it all together, aligned it and it still wouldn't crank. So they wanted to replace the wiring harness. They had it for 4 months and couldn't fix it. I got the car months after all this was done really cheap. Not being conceited but I'm an electrician and thoroughly trained to component level think I can do this with the info. So.... the EWSIII model and DME only have 200 maps and a new one generated everytime you turn the key <10 sec apart. Once you try to crank the car and it don't (after 200 times)then you get my simptoms. I found out later that they changed a fuel pump because they could start the car with starting fluid but it would run. This was after bmw had it for months. Why didn't bmw find the fuel pump bad? How many time did they try to crank it without fuel? 200? Anyway, the guy I bought the car from had bought a dme from ebay and if he tried it at anytime then the rolling code between the ews and dme would be off. Because if you turn ignition on without the proper dme and map selection the car will let starter spin and not send signal to injectors and coils. My exact problem. So I've got the carsoft and cables coming to realigned the software and I'll know more

[dghahn]

Did you ever find a resolution to your problem?

I have the exact same issue, 99 z3, wouldn't start one day. I have:
- replaced crank sensor(twice)
- replace dme(had mine cloned to a new one)
- replaced cam sensors
- tested all fuses/swapped all relays
- tested for power and ground at DME

I am also waiting for the DIS software and cable, but I have little hope that it will show anything.

#4




Same problem
Did you ever find a resolution to your problem?

I have the exact same issue, 99 z3, wouldn't start one day. I have:
- replaced crank sensor(twice)
- replace dme(had mine cloned to a new one)
- replaced cam sensors
- tested all fuses/swapped all relays
- tested for power and ground at DME

I am also waiting for the DIS software and cable, but I have little hope that it will show anything.

[thejlevie]

A full up diag system will tell you if EWS is preventing the engine from starting. And that should be the first check done.

[bmwdirtracer]

+1. I'd also go back to the fact that the previously mentioned vehicle supposedly would start and run on starting fluid. That would mean it was getting spark. And that would mean the EWS wasn't at fault.

But your statement that you replaced your dme worries me just a bit, because "cloned to a new one" or not, I believe you'd still have to align the dme with the ews. When you get your DIS, it will be able to tell you if the EWS is involved.

When you swapped your relays, are you absolutely sure that you swapped in relays with EXACTLY identical pictures on the sides?

[dghahn]

Thanks for the quick replys...

The strange thins is that on my z3 it will start with starting fluid, but I've checked three coils and none had spark, but I tried them on my 323 and it showed a great spark. Something has to be sparking to get it to start with starting fluid.

I was concerned about the DME swap also, but from what I've read in the forum, if the DME didn't match the EWS it shouldn't even turn over, but the starter cranks easily. The place that did it needed the mileage and VIN. Not sure if that matters, but they didn't have the EWS. It is doing the same thing now as it did before the DME swap.

I swapped the relays from the working 323. I swapped based on color, but I'll check the the relays again tomorrow.

[bmwdirtracer]

There's no way you can align the dme and the ews without having both units in hand, as far as I am aware.

Whether the starter cranks or not, with dme/ews alignment incorrect, depends upon the year of the car, I think.

http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

on page 121 of the adobe document you'll be led to, you'll see that the "start (crank)" circuit, although going through the EWS, seems to depend entirely on the clutch safety switch, not upon the ews receiving other inputs, like correct shared codes with the dme.

I'm pretty sure your car will crank without even having the dme in place, but it sure won't start. Personally, I'd suspect that your new dme needs to be aligned with the ews.

As Jim pointed out, a quick trip to a full BMW diag system will show this instantly; a really good system will be able to align the modules.

[dghahn]

Thanks BMWDirtRacer,

I have the DIS software loaded up, I'm just waiting for the INPA cable to do the full test.

Your point about the EWS is interesting. I would imagine I can test the theory by unplugging the DME and see if it cranks. If the start cranks then it proves that there is no tie between the DME and EWS for cranking. Although the problem was exactly the same before I replaced the DME, but now I may have two problems.

[dghahn]

I tried using the inpa/ediabas software, but the cable that I used was a k-line inpa cable, and apparently the 99 z3 requires a d-can cable.

So, long story short, BMWDirtRacer was absolutely correct. I took the Z3 to a local shop and they re-aligned the dme and ews and the car started right up.

The 99 z3 uses version 3 D EWS, which is different from earlier versions. This version will allow the engine to crank, but will not start if it is not aligned with the DME.

Thanks everyone.

I tried using the inpa/ediabas software, but the cable that I used was a k-line inpa cable, and apparently the 99 z3 requires a d-can cable.

So, long story short,thejlevie and BMWDirtRacer were absolutely correct. I took the Z3 to a local shop and they re-aligned the dme and ews and the car started right up.

The 99 z3 uses version 3 D EWS, which is different from earlier versions. This version will allow the engine to crank, but will not start if it is not aligned with the DME.

Thanks everyone.

[sharky1]

The engine "starts" because it is dieseling off the starter fluid. It has a MUCH LOWER flash point & can fire on just compression!No spark is needed(so many people assume spark BC of this).
Yup, the car WILL run with no crank sensor (one or more cam sensors need to work).
I have a 1998 z3 same systems, I put a ebay ews 3d + Dme+ transponder & it starts....I believe it just needs to be aligned .
I am looking for a mail in alinment service as we dont hve anyone here to do it. What is the cheapest DIY way??

[bmwdirtracer]

The engine "starts" because it is dieseling off the starter fluid. It has a MUCH LOWER flash point & can fire on just compression!No spark is needed(so many people assume spark BC of this).
Yup, the car WILL run with no crank sensor (one or more cam sensors need to work).
I have a 1998 z3 same systems, I put a ebay ews 3d + Dme+ transponder & it starts....I believe it just needs to be aligned .
I am looking for a mail in alinment service as we dont hve anyone here to do it. What is the cheapest DIY way??

This is a 5 year old thread. It was resolved accurately.

While a gas-engined car can certainly compression-ignite starting fluid, the result is never pretty, nor would it be described as "starting and running". More like fireworks, and most often, destruction. I much prefer carb cleaner, or even brake cleaner; both much less volatile than starting fluid.

"I have a 1998 z3 same systems, I put a ebay ews 3d + Dme+ transponder & it starts....I believe it just needs to be aligned ."

If it starts, the dme and the ews are aligned. The codes must match, before spark and fuel are delivered, with a BMW. Volkswagens are different; they start, and then shut off, if the immobilizer is pissed off.

If a BMW starts, and then shuts off, I'd suggest connecting a fuel pressure gauge, and reading all the codes in all the computers. {There will be codes for a pissed off EWS. There will not likely be codes for a bad fuel pump, or impaired fuel delivery.} But again, a BMW doesn't start until the EWS and DME agree they're on the same program.

[sharky1]

While a gas-engined car can certainly compression-ignite starting fluid, the result is never pretty, nor would it be described as "starting and running". More like fireworks, and most often, destruction. I much prefer carb cleaner, or even brake cleaner; both much less volatile than starting fluid.

"I have a 1998 z3 same systems, I put a ebay ews 3d + Dme+ transponder & it starts....I believe it just needs to be aligned ."

If it starts, the dme and the ews are aligned. The codes must match, before spark and fuel are delivered, with a BMW. Volkswagens are different; they start, and then shut off, if the immobilizer is pissed off.

If a BMW starts, and then shuts off, I'd suggest connecting a fuel pressure gauge, and reading all the codes in all the computers. {There will be codes for a pissed off EWS. There will not likely be codes for a bad fuel pump, or impaired fuel delivery.} But again, a BMW doesn't start until the EWS and DME agree they're on the same program.

While a gas-engined car can certainly compression-ignite starting fluid, the result is never pretty, nor would it be described as "starting and running". More like fireworks, and most often, destruction. I much prefer carb cleaner, or even brake cleaner; both much less volatile than starting fluid.

"I have a 1998 z3 same systems, I put a ebay ews 3d + Dme+ transponder & it starts....I believe it just needs to be aligned ."

If it starts, the dme and the ews are aligned. The codes must match, before spark and fuel are delivered, with a BMW. Volkswagens are different; they start, and then shut off, if the immobilizer is pissed off.

If a BMW starts, and then shuts off, I'd suggest connecting a fuel pressure gauge, and reading all the codes in all the computers. {There will be codes for a pissed off EWS. There will not likely be codes for a bad fuel pump, or impaired fuel delivery.} But again, a BMW doesn't start until the EWS and DME agree they're on the same program.

A gas engine CAN'T run on a less volatile fuel if it has NO SPARK...it CAN diesel on starting fluid as it has more kick.

Yes, of course the DME/EWS were aligned ON THE EBAY DME/EWS/TRANSPONDER! And, YES it started!
In the end, I was CORRECT, a ews/DMW alignment was what was required as I thought.

And again, the car didn't start, it dieseled off the starting fluid and yeah, it isn't good for the engine but proves a point as I mentioned it as many have posted no starts but runs a short time off starting fluid. No one suggested driving a car around on starting fluid!


To reiterate, a dieseling engine requires no spark, nor injector pulse, simply proper cam/crank timing & rotation.