Ray3

So, after owning my SC4 for only a few months it decided to not start. (Crank, no start) I thought that after snooping around on this and other forums that my problem was a bad fuel pump. I thought this due to not hearing a fuel pump when the key was in ON. Well I tried the bypass at the test connection on the engine. Hooray, fuel pump sounds when in on.
Alas, Crank but no start.

Ray3

Thinking it's a bad fuel filter I checked on the down stream side of the filter. Yes, there is fuel. Guess it's not a fuel issue.

Ray3

Now at this point I had the Crank no start had happened only once before and after letting it sit for 5-10 min it started and I drove home. So now I have drained the battery more than once trying Crank it. It seemed funny that there was no gas smell from the exhaust.

Ray3

Now I think that I should check spark and compression. I have a hard time believing that I should have compression failure that would keep it from at least trying to start, since it was just running.

Ray3

With no spark and good compression I started to think my main ECU is bad and that maybe my capacitors failed. Perhaps it started to go the first time it did not start and now it's completely dead. Out it came, didn't look like bad at all.

Ray3

So before I send it out to have the caps replaced (I may do it any ways) I decided to to check all the fuses and relays. All good. Well I was at a loss, I didn't want to just start replacing things that I didn't know were bad. Let's check the crankshaft position sensor.(or engine speed sensor)

Ray3

During removal if the Crank position sensor the bolt holding it in broke and the lower portion of it was full of dirt or at least some kind of junk. I was unable to remove the sensor in one piece. But the resistance was 2k and about 1k on the new one. Not a smoking gun because of how mangled the old sensor was, but a start.

Ray3

Didn't feel bad about replacing the crankshaft position sensor since I destroyed it. All the dirt in the hole kept the new sensor from fully seating. Used a pick, scotch bright, and sand paper to smooth the edges and clean it up. This wasn't working, so I used a brake cylinder hone. This worked great. New sensor installed.

Ray3

I figure it can't hurt to try to start it.

Vroom!! Yippee!

Started immediately (Even after sitting for 3 months since it failed to start) all that for a $20 Crankshaft Position Sensor.

Ray3

Next step buy a new under engine cover since without one I think that let dirt at it. Maybe one of those fancy aluminum ones

RudysSC

Glad to hear you got it all sorted out man! Nice work diagnosing it.

Fathead510

where is this senor?

Fathead510

where is the senor location?