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The mkiv Supra Owners Club

Engine will not fire (no Spark)


T2 MSW

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It looks like the cam sensor has gone. Monitoring the CAM input and the crank input on the syvecs at 5Hz can see the pulse of the crank but nothing from the cam sensor. Eventually got to the sensor and measured its resistance and that checks out just ok. So going to replace tomorrow and try that.

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IIRC the Syvecs only uses one of the Cam sensors, so you should be able to swap it with the other one that isn't used.

 

Thats correct it does. Unfortunately the other one is so badly damaged its almost impossible to get wires on it. May just get away with it to test it. But need to get a replacement.

 

having never looked at the logs I don't know if the cam is meant to pulse like the crank though, would have thought it should as it's the same type of sensor. Also found something out about the syvecs I'm not very impressed about today as well. It doesn't know if sensors are damaged, you can completely disconnect the cps sensor and it doesn't even throw up an error.

Edited by T2 MSW (see edit history)
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Not sure if yours is still connected to the Syvecs, but when I had some work done, the coolant temperature sensor was snapped off and stopped the car from starting, once re-wired and re-attached all was fine again. Seriously, check this as it is a real possibility!

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Just a thought mike but do you still have the alarm?

I would be tempted to just wire it all back in exactly how it was to see if it changes anything, I know it only 2 wire that stop it starting but there are other wires connected to locks,windows and other choice switched lives , you have nothing to loose at this point apart from the hour putting it back in.

Edited by mellonman (see edit history)
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Just thought I would chip in before it's discounted. The water sensor does indeed stop the car from firing. It had be scratching my head for absolutely ages. It's the lower one on the radiator that does it. I have no idea what it's called or where the temperature goes to on the ECU, it definitely stopped my car from firing though.

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Its 100% nothing to do with alarm or water temp sensor. Ive been through everything electrical today and its all correct. Logging on the ECU is showing pulse from the CPS sensor but nothing from the CAM sensor.

 

Have also put the CPS sensor on the cam wiring - thats works fine

CAM sensor on the CPS wiring and that also has no signal. Every so often it pulses.

 

So need a new CAM sensor.

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Problem fixed. The lack of signal from the cam sensor was the issue. Happy it's fixed but disappointed in the Syvecs that it didn't flag any errors even when you completely disconnect to sensor.

 

Can you not customise the warnings that it puts up? So that it'll red flag if it doesn't see a cam sensor signal?

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Sensor itself. New one and the ECU started getting a signal.

 

Im going to have to spend some time learning the ECU capabilities and how to check warnings etc as I'm seriously not impressed it doesn't even notice if the CPS or Cam sensors are disconnected. Doesn't fill me with confidence that of the fuel pressure dropped it would save the engine.

Edited by T2 MSW (see edit history)
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Can you not customise the warnings that it puts up? So that it'll red flag if it doesn't see a cam sensor signal?

 

The point is, if this can be done I would expect it already configured, I paid a lot of money for someone from Syvecs to map

the car.

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The thing is Mike if a cam or crank sensor fails its not gona damage the engine it`ll just cut out, i tried the important cuts manually on mine ie fuel/oil pressure by disconnecting the sender while the engine was running and it cut out instantly, oh and i tested oil pressure trip at the ring by entering a corner abit quick lol so i adjusted the trip setting by a few psi.

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The thing is Mike if a cam or crank sensor fails its not gona damage the engine it`ll just cut out, i tried the important cuts manually on mine ie fuel/oil pressure by disconnecting the sender while the engine was running and it cut out instantly, oh and i tested oil pressure trip at the ring by entering a corner abit quick lol so i adjusted the trip setting by a few psi.

 

Oh yeah I agree its not a massive thing but I would expect the Syvecs to flag an error if say the CPS sensor was not connected. The voltage goes from 1.65V to 5V so the ECU must know.

 

I think thats what I'm going to have to do test them manually. Ill let the car idle and Disconnect the fuel sensor and ensure the ECU kills the car. Do you know where the sensor trips are in the syvecs so I can adjust that for oil pressure and again ensure it shuts it down.

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