P3191 After EGR cleaning

Check the PCV hose is plugged into intake manifold. Otherwise it’s a massive vacuum leak. That one has tripped me up.

 

How massive is massive?

 

It's likely something is not connected properly, since it was running fine before the work.
Check ALL connections again, carefully, slowly. Did you pinch a wire?
The P3191 code is for the camshaft position sensor.
P3191 Code Meaning, Causes, Symptoms, & Tech Notes (With Video)

 

Gas tank vapour hose connected to intake manifold? That’s just below throttle body.

 

If it starts and runs and then dies pretty immediately or whatever you probably have your vacuum covered a PCV or a gas tank vent largely like that would probably not allow the two ZZ Atkinson to start The electric motors will back you up or whatever reverse but as soon as the engine tries to start backing up far enough or whatever it'll spin over you'll hear it try to turn the motor on activate the coils whatever and it just won't do it and it throws the 3190 91 whatever poor engine power so on and so forth yeah because there's none remember the reciprocating mass is turning all the time no matter what you're doing with the car in forward or reverse so the Pistons are going up and down the computers just haven't turned the coils in the fuel on.

 

The description for P3191 is "Engine does not start." There are many reasons why the engine may not be starting. The camshaft position sensor is only one of many possible reasons. Here is a list of other reasons why the car is not starting:

1. Intake system (possible vacuum leak)
2. Throttle body assembly
3. Fuel pressure
3. Engine
4. Mass air flow meter sub-assembly
5. Out of fuel
6. Engine coolant temperature sensor
7. Crankshaft position sensor
8. EGR valve assembly
9. ECM

I would check the other possible reasons before I would check the camshaft position sensor.

 

Okay, my mistake. I have no idea why I wrote that about the cam shaft position sensor.
But, I DID include the article, so if anyone just read the article..........

 

AFAIK there’s 2 “air” hoses, the PCV and gas tank vapour. If either end of either is disconnected your engine will only “run” for a few seconds.

 

For those looking for other possible solutions, I had this same issue and could find no hoses or wires disconnected. Checked and re-checked everything, including putting old spark plugs back in, old engine air filter back in. I have a 2015 Prius C but I don't think it makes a huge difference.

When I cleaned my EGR, I tool the electric actuator part off so I could depress the EGR valve manually and get some cleaner in it. I think when I re-assembled it, it must not have threaded the magnet all the way back on. The magnet is the grey cylinder with a spring under it - it threads onto the shaft of the EGR valve. Didn't get a pic of it but it is inside this black housing with the plug on it:



Anyway, I took the electric part back off (leaving the EGR installed in the vehicle), inspected it, threaded the magnet back on a bit tighter this time, re-assembled and the car started smoothly after that. I suspect that the EGR valve was stuck (open or closed, not sure which), which was causing the issue.

Hope this helps someone.