Car stalling and reving weirdly

[Pav0072]

Hey all,

i was driving home from a friend and the car felt almost like when your tyres slide a little on dirt when you give it a full throttle feeling but it was doing almost in like 2 second intervals. Then it started stalling weirdly when in higher gear for a certain speed, but in a really weird strong way. When i stopped at the traffic lights the sound of idle was very strange, almost like a lawnmower or something like that and the rpm went slightly lower and then taking off on first gear was really difficult the car almost stopped completely it was stalling. The engine light came on with EPC

I was thinking this could be crankshaft sensor or maybe throttle position sensor. Anyone got any idea what it could be?

 

[andymr1983]

Hey all,

i was driving home from a friend and the car felt almost like when your tyres slide a little on dirt when you give it a full throttle feeling but it was doing almost in like 2 second intervals. Then it started stalling weirdly when in higher gear for a certain speed, but in a really weird strong way. When i stopped at the traffic lights the sound of idle was very strange, almost like a lawnmower or something like that and the rpm went slightly lower and then taking off on first gear was really difficult the car almost stopped completely it was stalling. The engine light came on with EPC

I was thinking this could be crankshaft sensor or maybe throttle position sensor. Anyone got any idea what it could be?

Did you get to the bottom of this? Similar problem on my 2014 6J. EPC, Engine Management light and Traction Control Light on dash, car in limp mode. Green Flag tech advised it was either the pedal position sensor or the throttle position sensor. I swapped the pedal out but the problem persisted so I'm now waiting on a throttle body coming. Oddly though, problem appears to be gone when the engine is cold, no faults show up and Carista shows no faults at ODBII or ECU. It reappears when the coolant warms up. Tested this today by just turning the car on and idling. Coolant temp reached 70 Celsius and the engine just died with the EPC and TCS light back on the dash. Idle didn't feel rough as such, but did seem to have jolts.

 

[mty12345]

Did you get to the bottom of this? Similar problem on my 2014 6J. EPC, Engine Management light and Traction Control Light on dash, car in limp mode. Green Flag tech advised it was either the pedal position sensor or the throttle position sensor. I swapped the pedal out but the problem persisted so I'm now waiting on a throttle body coming. Oddly though, problem appears to be gone when the engine is cold, no faults show up and Carista shows no faults at ODBII or ECU. It reappears when the coolant warms up. Tested this today by just turning the car on and idling. Coolant temp reached 70 Celsius and the engine just died with the EPC and TCS light back on the dash. Idle didn't feel rough as such, but did seem to have jolts.

Lots of electrical faults are temp related. As the engine warms or cools, joints expand or contract. I would check the wiring on the connectors, although usually those symptoms are more often a circuit board fault. So i'd guess it's probably the circuit board inside the throttle body.

In my experience, most RAC/AA/Green flag people aren't great at diagnostics. Always best to get the car scanned with VCDS. That will usually show a lot more information on the fault that you will get with a general diagnostic scanner.

 

[andymr1983]

Lots of electrical faults are temp related. As the engine warms or cools, joints expand or contract. I would check the wiring on the connectors, although usually those symptoms are more often a circuit board fault. So i'd guess it's probably the circuit board inside the throttle body.

In my experience, most RAC/AA/Green flag people aren't great at diagnostics. Always best to get the car scanned with VCDS. That will usually show a lot more information on the fault that you will get with a general diagnostic scanner.

It was the throttle body, second hand one from eBay at £55 and I'm back on the road, all faults gone. Except the pesky TPMS errors picked up by my Carista, they don't affect running but I'd love to clear them at some point, not sure where to start.

 

[mty12345]

Ah i'm glad you got it sorted for a good price.

Can't advise on the TPMS as i've never had a car with it fitted, or worked on anyone elses.