Oil Temp Sensor: What happens if it is bad??

[87LtdT]

Would it prevent an engine restart if engine is hot??

I am having this exact problem (engine starts fine when cold, runs fine until shut off, but then will not restart until it cools down) after an engine swap during which I installed a used oil temp sensor purchased from a forum member.

I've replaced the crank sensor and ignition module during troubleshooting with no change.

When engine will not restart there is no signal to the injectors (Noid light doesn't light), and there is no spark from the plug wires.

Thanks, Bob

 

[rodman99999]

Where did you install this Oil Temp sensor? I don't find one mentioned in the factory manual.

 

[DailyDrifter]

Coolant temp sensor could cause this.

 

[GNVenom]

No spark, no fuel points to the crank sensor. It could have a bad connection, maybe a defective connector - either on the sensor or at the CCCI module.

Another thing to look at is the ignition switch. I've seen this cause no-start conditions a few times.

 

[87LtdT]

I should have said oil pressure switch (at the brass fitting supplying turbo oil supply line)....not oil temp sensor...apologies.

Daily...can you say more about the coolant temp sensor??

John, I appreciate your input...had planned to call you tomorrow. We have spoken about this around January....at lest I think we did

The car starts normally....repeatedly...when "cold"... but no spark or injector pulse when "hot". Same is true after crank sensor replaced, and same is true after Ignition module and coil pack replaced. We theorized the cam sensor cap could be involved, but wanted to wait until crank sensor and IM were ruled out.

Bob

 

[salvageV6]

Oil pressure switch isn't the problem, it's a redundant fuel pump +12 power circuit, and of course the idiot light at 4psi. activation points.

I'd double check the ECM with a spare.

Sounds like a module issue but you seem to have ruled that out...

 

[rodman99999]

Would it prevent an engine restart if engine is hot??

When you say, "hot": Do you mean, "overheated" or that the engine has reached operating temps? A faulty Coolant Temp sensor, or failure in the circuit, should set a 14 or 15 code. Is your SES light staying lit? Do you have a scantool? If so- What readings are you getting for coolant temps? To quote the factory manual, "Engine coolant temperature affects most systems that the ECM controls." If the Oil Pressure switch was bad, AND the fuel pump relay also: Your fuel pump would not turn on. Other than the indicator light in your dash(one pair of contacts in the switch-N.C.), and the Fuel Pump Relay bypass circuit(the other pair-N.O.): the Oil Pressure Switch has no other connections(can't affect your ignition circuit).

 

[DailyDrifter]

Daily...can you say more about the coolant temp sensor??

If a car is reading very hot it does not need as much fuel to burn. If your sensor is reading hot it wont put enough fuel in to run. You could also have a problem with the module getting heat soaked and causing a no start until it cools down.