bound to happen, carrera no start, possibly speed sensor?

[gunlover05]

just ordered 2 bmw sensors and a coil from the host. It may take a few weeks to get the time to install them, but I will circle back and let you guys know how it is going.

[SiberianDVM]

You didn't order the silver Brazilian coil, did you?

[88911coupe]

Wow, very timely...been running into same issue on my '88. However in my case the "no start" would happen after a 30 minute drive where I let the car sit for a few minutes then tried to restart. It would turn over fine but never fire. I took the relay out and noticed a broken/missing chunk of solder and ordered a new one from Pelican (KAE). BTW, I popped in the old "working" relay I kept in the glove box and car fired up. Then installed new relay but had same issue, car would (on occasion) not re start after 30-40 minute drive. I shook the relay and it fired right up...so assumed the new relay was buggy out of the box, which seemed really unlikely. Pelican promptly sent me a replacement and SO FAR has worked but I'm still suspicious. Tested the RPM/Reference sensors but I did it at the DME connection itself, both tested perfect and are the BMW versions installed during rebuild 2 years ago. Question to OP...did you car die at the red light? In my case the car runs perfectly while its running...only had issues on restarts. What confuses me is what to test on the relay if it happens again.

[89PS911]

Hi Sugarwood,

On the flywheel/cylinder end, I left the old wires dangling there poking through the hole leading into the engine bay (where the big rubber grommet fits), but cut off the sensor heads. I then just, one-by-one, tied the old wire ends around the plug side of the new sensor wires and then, as you say, fished them up through the engine bay to where the plug connectors are. That worked very well, and I am sure rubberbanding them would be even better so that wires don't separate from each other somewhere inconvenient in the engine bay.

Jonathan

[Liam O]

Twice in nine years my car wouldn't start, the first in 07 the second in 2013.
On both occasions it was the speed and reference sensors, replace both not one at a time like me.

[Liam O]

Nine years of ownership that is had the car since 06.

[gunlover05]

Originally Posted by SiberianDVM

You didn't order the silver Brazilian coil, did you?

oh not sure, I ordered this bosch from the host. it has a silver body and red top. did I make a mistake?

944-602-115-00-M14

[gunlover05]

yes 88911coupe, mine died while I was sitting at a red light.

[KNS]

Just to confirm - it's the same part for both speed and reference sensors... correct?

[Stutzdriver]

Yes, same part for both sensors. They can be a BI*CH to replace. Mine were corroded into the brackey so I had to remove the bracket requiring a regap which is easy. If you have to remove the bracket you wll need to take a corect diamete washer that you make into the correct thickness. Use a removable glue to glue the washer to the sensor, install the bracket and the gap is correct. My old sensors were destroyed in the removal process so i used the new sensors to set the gap. Its an akward place to get to and work on but be patient and don't get frustrated.

I used 2 of the BMW sensors form my local BMW dealership at $60.00 each. They are well aware of the issues with these sensors which either work or don't, no in between. The wire is about 8-10" longer so be sure to tie up the extra on the ENGINE side of the shroud.

Good news is this will correct things and you will be back in business.

[gunlover05]

Ok, some progress. I won't receive my new sensors till mid this week, but went ahead and wanted to try and get the old ones off the engine. After lots of awkward positioning, pb plaster, wiggling, cajoling, more pb blaster with some choice words, I was able to loosen and remove the two sensors without removing the bracket!!Definitely not easy, but the pb blaster was the trick. I will stop here until next weekend when I have the new sensors, I was satisfied today to get this far.

[SiberianDVM]

Originally Posted by gunlover05

oh not sure, I ordered this bosch from the host. it has a silver body and red top. did I make a mistake?

944-602-115-00-M14

No mistake on your part; you probably just joined the wasted money club. These particular Brazilian made coils have a poor rep for durability. Don't throw your old coil away yet.

[LarsM]

Hi there, why new coil?

[gunlover05]

oh great, thanks for the warning, I should have researched the good/bad coils more. with all of the noise on shoddy DME relays and other components, I guess buyer beware.

I only bought a coil because I could not verify mine was good in the current situation, and with being 30 years old, well It is suspect. I will definitely save my current one as backup/original.

[LarsM]

Can you measure the resistance on both your newly ordered coil and the old one when you have them both? just to see if there is a difference. The Bentley's got good instructions and datatables. Also, Can you start off by changing the sensors first? If I were you I would only change the sensors, and if they fix you problem, not swapping the coil if you do not have any starting issues...

[gunlover05]

yes lars i will replace sensors first since I've already pulled them out and try with old coil. I will also measure coil resistance of both. will be this weekend earliest

[gunlover05]

I literally just replaced both sensors, and it FIRED RIGHT UP! I did not replace the coil, I will either return it or keep it as a spare.

I am stoked, appreciate everyone's help here!!!! Pelicans are the best

[tomphot]

Fantastic!!
6 years ago when this happened to me, nobody on the forums were pointing toward the sensors as a problem area. As a result, I spent months doing all of those other suggested fixes before finding the problem. Glad it worked out for you.

[jlex]

Did you happen to measure the resistance at the harness connectors in the engine compartment with the bad sensors? Would be interesting to see what those readings were vs the readings on the two new sensors. Maybe higher resistance levels could be a clue that sensors are going bad...

[rick-l]

Originally Posted by jlex

Did you happen to measure the resistance at the harness connectors in the engine compartment with the bad sensors? Would be interesting to see what those readings were vs the readings on the two new sensors. Maybe higher resistance levels could be a clue that sensors are going bad...

From his first post

Originally Posted by gunlover05

Reference sensor I get 1k ohms (bottom I think), speed sensor (middle) I get no resistance at all.

The later is definitely an indication of a sensor going bad