odurandina

i have an unending urge to bump all 4,688 no start threads......

then do an all-in-one thread combine.

time for the

LIFE IN BOSCH OFFICIAL THREAD. Post your GD no-starts here;

EJZero1

Finally got a chance to swap out my boxes with known good DME/KLR units, thanks to a local European performance shop owner.

Swapped both boxes, hit the key, and it immediately fired up. Swapped back to my original DME, and no start. So I guess I've pretty much zeroed in on things.

Next step is to open my DME and try to determine if I can pinpoint the issue. Maybe the cold solder joints that have been identified as a possible root cause earlier in this thread. Maybe something else will be evident once I open the box.

We'll see. For now, I'm happy for the apparent progress.

More to follow.

EJZero1

Took my DME to my mechanic who opened it up and saw what he described as a few "suspect" solder joints. He broke out his soldering iron and spent some time going over all of the joints that he thought needed attention. Took it home, plugged it in, and still no start.

I'm about done chasing the gremlins that live in that little silver box, and am anticipating going with the new DME offered by Focus9Technology. Sent them an email the other day inquiring as the their compatibility with my M-Tune chipset. The response was quick, professional and to the point.

I believe I'll be placing the order in the near future. Can't wait to post the update that closes this thread.

Tom M'Guinn

At least you know what it is... Here's another option.

http://www.ecudoctors.com/porsche-94...261200075.html

EJZero1

Thanks, Tom.

I'm familiar with the ECU Doctor folks, and had used their video posted earlier in this thread in my troubleshooting process.

Always nice to have options. Bottom line prices are comparable, just need to compare the end product; Focus9's "modernized" DME versus ECU Doctor's rebuild version.

Will post up as I move forward.

Thanks again to everyone that's chimed in. Hopefully the troubleshooting discussed here will help someone else as they try to track down their own issues.

Tom M'Guinn

I think the ECU Docs do a great job and have used their boxes on several occasions, but I understand the desire to have a brand new solid state unit as long as it's functionally identical. I have one KLR that produces an odd tip-in bog on my car, even though it's been rebuilt by ECU Docs. I've tried swapping chips, and ECU Docs even supplied an extra to try, but the tip-in issue remained. With any other KLR it goes away regardless of chip. I assume "something" is not working right on the board, but still passes all functional testing at the bench level. No criticism of ECU Docs at all, who are always great to deal with, but old electronics are old electronics. My only concern about the new solid state version is whether it introduces its own quirks or compatibility issues? Presumably not, but would be good to hear from people who have used it to hear about any real-world issues or lack thereof...?

Otto Mechanic

To satisfy odurandina I won't start another thread on this subject. It seems there's a pattern of no start failures surrounding the Reference/Speed sensors and since this is a recent thread I think I'll bump it.

I have an S2, which only has one sensor. I recently replaced my clutch and notched the bell housing during that operation. I did remove the Reference/Speed sensor housing and carefully re-gapped the sensor using the 0.8mm specification from Clark's.

I also did some work on the driver's side door lock while I was servicing the clutch and doing some other things. This may have effected the alarm system. I don't know how the alarm locks out ignition, or how to bypass it if it has.

After putting everything together I tried starting the car today, it turns, I get a tach bump, but no start.

I put a Noid light on the injectors and got a signal. I put one of those "test" spark plugs in and got a spark.

I can't test my fuel pressure because the gauge I have from my 928 doesn't fit on the S2 fuel rail; the size and threads are correct but there's no space between the rail and the intake manifold so I can't put the gauge on. I'm looking for some sort of plumbing that will adapt my 928 gauge to the S2, so far no joy.

I'd like to rule out the DME and Reference/Speed sensor by the spark and noid tests. Is this legit? I don't have a spare DME/Fuel relay but I have one on order that should be here in a few days. If I can figure out how to put a gauge on the rail it would help a great deal. Suggestions welcome.

Mostly I'd like to rule out the sensor and DME and to know the spark/Noid tests have done that?

Thanks,

Tiger03447

can you hear the fuel pump run when you hit the key? You could leave the key on, crawl underneath the car and check for power at the pump. If you get power you could rule out the relay and start checking out the alarm circuit. There are threads and clark's on how to disable that..951 I'm not sure. Perhaps this could be of help.

Otto Mechanic

Tiger, thanks it does.

For some reason, I'd given the same advice to someone on this forum a few months ago and was told that test didn't work on the 944, that the pump engaged only when the key was in the start position or when the engine was running?

What you describe is the way my 928 works, but when I told the other person about it I was sharply informed of the difference?

I suppose I should try it myself and find out?

Regards,

Otto Mechanic

Just to close out part of this subject, I confirmed the fuel pump doesn't come on with the key in the "on" position on a 944 S2.

I pulled the DME relay, jumpered it as described in Clarks (30 to 87b IIRC) and the pump didn't come on. Lifted the car and went to unplug the pump connection before applying 12v direct to the pump and found the connector loose. Uncliped it, re-seated the connector, pump started.

Unfortunately the car still doesn't start. I have:

- Signal to the injectors (checked with noid light)
- Spark (checked with test plug)
- Working fuel pump

I suppose it could still be the DME relay. I swapped it with a URO relay and that didn't help, but I've read those relays are often DOA. I'm waiting for either:

- Adapters to fit my fuel pressure gauge to the S2 fuel rail (next week)

or

- Another OE DME relay I can trust (also next week)

Looks like I have multiple problems. I don't know if I've ruled out the DME itself or the Reference sensor by getting spark + noid signal.

I also don't know what symptoms to expect from an alarm fault; does the alarm cut off fuel or spark?

Arominus

You need to go buy the retrofit kit for notched bellhousings from Porsche stat, the part you removed provides magnetic shielding to the Ref sensor. eventually the starter will cause enough interference to cause the ref sensor to read incorrectly and it will cause a kickback while starting. It took me 2 years to find this issue on my S2. Get the new bracket and sleeve for the sensor.

Otto Mechanic

There was an aluminum sleeve on the reference sensor I have. I did notch the bell housing.

You're suggesting there's a different sleeve for the sensor? Not part of the '89 assembly?

Regards,

Arominus

My car did not have a separate aluminum sleeve for the sensor initially, so the notch messed with it. If yours has the sleeve and it covers to the tip of the sensor and then inserts into the bracket, you are ok.

Otto Mechanic

"Get the new bracket and sleeve for the sensor. "

You wouldn't, perchance, have that part number at hand would you? I have cookies to trade...

Otto Mechanic

Sorry Arominus, I really am a bit desperate here. I'm just trying to limit my investigation. If I can rule out the reference sensor that would be good and I could move on. Consider it some weird sort of Triage?