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I have a friend that drives grub hub and has been having issues with the car dying a few times the last couple of weeks but only after ~2.5 hrs of driving. It turns over and tries to run but gets really rough and dies out. Then after it sits it will run fine. I'm thinking it has something to do with the prolonged heat on maybe a solenoid, actuator, electrical connector, or ECU?

Thanks for any help you can provide
 

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First thing to check is CPS (crankshaft position sensor). Check tach while cranking when engine doesn't want to run. If tach moves slightly CPS is OK. If not, CPS is bad.
 

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First thing to check is CPS (crankshaft position sensor). Check tach while cranking when engine doesn't want to run. If tach moves slightly CPS is OK. If not, CPS is bad.
Thanks!!

Would CPS go out only intermittently after running the car for 2-3 hours and run like **** or not at all or just fail and not work at all? Maybe from heat soaking it fails and then it cools back down and works. It expands from heat and looses continuity, then where ever it’s loosing contact /connection/continuity touches again when it cools and shrinks back down? That’s the only thing that would make sense rather than just failing and the fact it’s only after she drives it for a pretty extended time with a lot of stops which cause serious heat soaking under the hood.

How difficult or hopefully easy is it to get to? Is there a way to test it? Wouldn’t it through a DTC and stay within the ECU until it’s cleared by a diagnostics tool? I’m going to just swap it out as cheap as it is. Do you recommend any brand to use or stay away from?
 

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1) Yes
2) CPS is a generator. Its magnet weakens from temperature and shock over time, and it stops working internittently as its output decreases...
3) slight difficulty - most of it is accessing CPS (see step 3 below)
4) test with mulltimeter while cranking car; you should measure AC voltage, resistance should be ~860 ohms. Also, see post #2 in this thread.
5) No
6) Bosch only
cps.png
EDIT: correct MY and step in diagram
 
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