M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => General Topics => Topic started by: deansweet on May 20, 2014, 06:27:58 PM
-
He calls and tells me his car has this peculiar issue where he starts the car the 1st time of the day it fires up just fine, if he stops and restarts the car within a couple minutes or longer than 15-20mins the car will not restart? For example, approx time it takes to fill the car up is 4-5mins. This is too long so it won;t start and has to sit there or push it aside for 15-20mins before it restarts. He brings it home and it sits in my garage as he drives the dreaded Fit(none of the kids like the Fit?) and I start tinkering. I find out that during the won't start cycle I have no spark. I pull and test the piece of shite plastic 'engine speed sensor' that we normal folks call the crankcase sensor and it is reading a bit high. It is supposed to be 500-600ohms and mine is reading 988 and from what I can determine this means the sensor is questionable. I am guessing that the heat soak the sensor was getting from engine was causing a less than usable reading. I look online and find out the oem ones are $120 so I call my local dealer and order one from them as I get a 15% discount and would rather support them(local).
Here is the car waiting for its new part:
(https://lh6.googleusercontent.com/-kKhVa0oaYHY/U3vhuk6xihI/AAAAAAAACao/FBuWFYX6908/w755-h566-no/Garage+Trio.jpeg)
I got the part Monday and installed and has been starting like a champ ever since. I have had my younger son driving the 318i Mon-Tuesday as I would rather it die closer to home than in Cincinnati. Since it has been just sitting there I decided to polish it up. Some clay barring, Meguier's M105 on hood, trunk and roof since they were a bit faded, M205 on entire car then a final coat of Collinite's #845 insulator wax. It's so smooth. I'm betting its been 10+yrs since it had been thoroughly waxed. My son is going to freak.
Results:
(https://lh4.googleusercontent.com/-xXnbsHoDA6k/U3vhumkpY-I/AAAAAAAACak/8L0FpU4OAyU/w755-h566-no/Chads+Car+Cleaned+up.jpeg)
-
Looking good, glad the fix was simple!
-
Couple more pics:
(https://lh6.googleusercontent.com/-2E-QVj_jJeY/U3vwFjMLi9I/AAAAAAAACbU/6AwN5tgzVhM/w755-h566-no/Chads+Hood+Side.jpeg)
(https://lh5.googleusercontent.com/-bOmgFeOcCvU/U3vwEi90HpI/AAAAAAAACbY/Hg1HelsdDAw/w425-h566-no/E30+M42+Crank+Sensor.jpeg)
-
Glad you go the crank sensor from the dealer. i hear a lot of stories about the aftermarket sensors.
Another thing to keep in mind is the "freeze" spray you can get from electronics stores that you can use to test various electrical items. if the problem goes away after you hit it with the freeze spray, you are probably onto something!
-
its amazing what a little elbow grease, time and effort can do to paint; car looks amazing.
if i may inquire (and mind you im not exactly an electrical engineer) how do you test the ohms on the sensor? is it as simple as unplugging it and testing the connector on the sensor, or testing the socket it would connect to? i am having a similar problem (except mine just wont start. no crank, no fuel pump prime)... it happened suddently and it now jsut sits there giving me a sad look
-
You're a pretty swell dad.
When he comes back, seeing his car all shinny and asks for the keys. You should tell him "no no, you're keeping the Fit".
LOL
-
its amazing what a little elbow grease, time and effort can do to paint; car looks amazing.
if i may inquire ... a sad look
Amen! That car is a treat. I'm tempted to go buy those products to do the same thing!
Dick: I don't want to clutter up Dean's thread - I'll update this question in the problem thread you started...
-
its amazing what a little elbow grease, time and effort can do to paint; car looks amazing.
if i may inquire (and mind you im not exactly an electrical engineer) how do you test the ohms on the sensor? is it as simple as unplugging it and testing the connector on the sensor, or testing the socket it would connect to? i am having a similar problem (except mine just wont start. no crank, no fuel pump prime)... it happened suddently and it now jsut sits there giving me a sad look
It's bit tough to hold the sensor and poke the two tabs inside the connector. You could take a couple smaller speaker lead plugs with a foot or so of wire and use those? Or you could ask somebody to hold the plug for you? and the vice grips are barely holding it so be careful not to squeeze it too tight. And have yout ohm meter set at highest at 1st which is more than likely 20k, if it does nothing then drop to 2k, etc. 2k should work.
(https://lh6.googleusercontent.com/-nGxyXPhfPXo/U309WbB8Q3I/AAAAAAAACb4/ktDZQ5-UL-4/w425-h566-no/Testing+Sensor.jpeg)
-
so i just tested my CPS (finally got a working DMM) and mine is at 530 +/- 10 ohms. would this indicate a faulty sensor, causing no engine turnover or fuel prime?
-
so i just tested my CPS (finally got a working DMM) and mine is at 530 +/- 10 ohms. would this indicate a faulty sensor, causing no engine turnover or fuel prime?
Nope, supposed to be 500-600 so yours seems good.
My engine would turn over, just no spark.
So yours does nothing when you twist the key in ignition? No fuel pump(Remove back seat bottom if you can't hear it clearly), no clcking from starter, how about dash lights?
-
so i just tested my CPS (finally got a working DMM) and mine is at 530 +/- 10 ohms. would this indicate a faulty sensor, causing no engine turnover or fuel prime?
Nope, supposed to be 500-600 so yours seems good.
My engine would turn over, just no spark.
So yours does nothing when you twist the key in ignition? No fuel pump(Remove back seat bottom if you can't hear it clearly), no clcking from starter, how about dash lights?
i can hear 1 click from the starter when i go to ignition on as well as off, and i hear a quick "3" clicks when i go this as well to ignition on. can not hear the pump priming unless i jump the relay via paperclip. all lights work flawlessly and do not dim when i go to turn it over.
I just went down and tested a few electrical components, here is what i found:
1) 12V @ main relay point with key in start and without. Continuous.
2) 12V @ fuel relay with key in start.
3)12.3V @ starter no key inserted.
4)12V @ starter with key in start.
--- both tests utilizing the big strap on the starter (M42 starter, strap on driver side of the starter) and a viable ground.
5) 11.8V @ fuel pump between pins 1/3 key in start.
-
with all the spark plugs out, does the motor spin clockwise easily by main crank bolt?
If not, pull the starter and try again.
For fun, check the voltage at the stater with somebody in the car actually turning the ignition to start the car.
My guess is you may see a massive drop in voltage? Might be that your starter pinion is seized with main and it's not able to spin.
If you end up pulling starter and your motor still does not spin by hand then it may be a bigger problem...