Oil Level Sensor Wiring - No crank condition

[Snappycritter]

I had a very unusual 'no crank' situation that seemed to have been caused by faulty wiring at the Oil Level Sensor connector (insulation stripped about 1in/25mm on both wires and hidden by the remnants of the original split-loom tubing and electrical tape). Next time you folks do an oil change, you may want to inspect this wiring.


1) Suspecting the starter, I replaced it w/ a reman. NAPA gear reduction starter and still had a no crank condition.

2) IPC would go black along with headlights when key was turned to start

3) in an OCD moment, I decided to replace the split-loom tubing that fed the Oil Level Sensor since I already repaired the main bundle that fed the starter, etc.
***at this point, the car cranks***

I had a lot of fuel in my oil so I cannot figure-out how that occurred.

Is there a sensor that, when presenting a failure mode, cuts-out only the ignition?

[BobbyBubba]

Guessing here- Is'nt there a cut-off when the alarm is tripped? Or- maybe BAD oil level sending unit (shorted)? NO OIL= NO IGNITION?

[padgett]

Thought the level was just a warning (have seen it before with not effect on running). Oil pressure has an interlock with the fuel pump - if you lose pressure, the fuel pump turns off which shuts the engine down.

[Richard D]

Didn't Chevrolet start that with the 1971 Vega? No oil pressure, no fuel pump.

[Corvanti]

I had a lot of fuel in my oil so I cannot figure-out how that occurred.

i think i'd be more concerned about that before dealing with the other problems!

"one thing leads to another"... (appropriately, the band's name was "the fixx").

[padgett]

Yes & the original one relied on residual gas in the float bowl for starting. When I put dual quads on my '78 Sunbird I had to add a prime button on the dash. When computer controls came along in the '80s they added the two second prime shot (only purpose of the fuel pump relay).

[Snappycritter]

It may be easy to verify this fault condition if the connector is pulled and a short wire shorts its terminals. All I know is that there were no other alterations to the vehicle (except a new fuel filter, oil filter & oil, starter). New starter still gave the 'no crank' condition until the Oil Level Sensor wiring was repaired.

Does anybody have any ideas about the fuel getting into the oil (past the piston rings is my assumption)?

Every fuel injector showed 14ohms.
Fuel fouled spark plugs.

I will test for spark at the plugs (pulling the fronts - one at a time - and resting one on the block ->ground) tonight.

Should I check the crank position sensor first?

[zoltanb]

Pull the vaccum line off the fuel pressure regulator to see if it is leaking, also swap the fuel pump relay with the abs relay. If none of that helps check the compression. this all is to see how you got so much gas in the oil.

[Mc_Reatta]

There's no connection between the oil level sensor and the cranking system. You had a problem elsewhere. Do you have a 90?

If the car runs, there's no need to suspect the Crank sensor. If that's bad it won't start.

If zoltanb's checks don't pan out could be leaking injectors or bad ECM.

[Snappycritter]

Thanks gang!

I will look into all of your suggestions and report back to you when I have some data.

[Ronnie]

Welcome to the forum Snappycritter! Please add the model of your Reatta, (and any other relative information), to your signature line. It will make it easier for us to help answer your questions without repeatedly asking you about the specific model you own.

Click "User CP" in the menu at the top of this page and scroll down to "Edit Signature"

Thanks!

[Snappycritter]

I'm going to test the CPS.

Will a normal test light work for the test, or is the LED used in order to protect the circuits (due to the LED's low current draw)?

[Ronnie]

LED is needed. Instructions for making a test light are on my website..

[Snappycritter]

Thanks so much Ronnie!

I had a bunch of super-bright (red) LEDs lying about, and all I needed was a 470 resistor for 12Vdc operation. Some E-tape and I'm ready to test! (it looks ghetto, but I'm not being graded on it - hahaha).

[Snappycritter]

I had a fuel injector stuck-open that hydro-locked its cylinder. I may still have an iffy VATS, but I can work around that if need be. I ordered a set of Delphi III fuel injectors from Fuel Injector Connection and will report back.

FUEL INJECTOR CONNECTION - 3.8 V6 Bosch III Fuel Injector sets

PS. Crank Position Sensor proved to be okay (good x3 & x18 signals). Thanks Ronnie!

PSS. any normal LED w/ a series 470 ohm resistance can work.

[Ronnie]

Thanks for letting me know the test procedure worked for you.

[Snappycritter]

It was definitely a fuel injector that was "stuck-open."

Starter was fine all along - but now I have a new one.

It may be second nature for more experienced folks, but I believe it's important to verify that the engine can rotate fully (4x revolutions minimum) when faced with a No-Start/No-Crank condition

I installed some Bosch IIIs from Fuel Injector Connection (19lbs w/ 4-hole pattern) and after Block-Learn completed - she purrs like a newborn kitten. I will report back with drivability results soon. Thanks for all of your help!

[Snappycritter]

It was definitely a fuel injector that was "stuck-open."

Starter was fine all along - but now I have a new one.

It may be second nature for more experienced folks, but I believe it's important to verify that the engine can rotate fully (4x revolutions minimum) when faced with a No-Start/No-Crank condition

I installed some Bosch IIIs from Fuel Injector Connection (19lbs w/ 4-hole pattern) and after Block-Learn completed - she purrs like a newborn kitten. I will report back with drivability results soon. Thanks for all of your help!

New plugs (RapidFire #3s), wires (Bosch 8mm), fuel injectors (Bosch III from Fuel Injection Connection) and it is smooth as butter. She passed emissions with flying colors - I mean she did better than an a 4-cyl from back in the day (Lebaron GTC w/ 2.5L Turbo).

One can of Seafoam (TM) and it smoothed-out even more. She has more apparent power. I highly recommend this (Bosch III) fuel injector upgrade for a daily driver.

If you go for the Bosch III fuel injector (4-hole spray pattern) I have some tips:
1) generously lubricate the injector O-rings (I used 5W-30)
2) following the port's alignment, gently press the injector into the port (you may feel the "lower" O-rings slide & seat).
3) the Bosch III "middle" O-rings simply rest against the port's chamfered feature (once you see that middle O-ring hit metal - you're dune pressing the injector in.
4) The Bosch III doesn't require the retaining clips
5) Gently press the fuel rail onto the protruding injectors (they'll give a dull "popping" kind of feel when they seat).
6) It may go without saying but it is important to clean every interface that the new injectors mate to (intake port/orifice and fuel rail ports).
7) Go to ECM and clear all codes
8) Let idle for at least 15mins.
9) Test drive
10) Smile