Technical Non starter
- Thread starter johnpu
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Technical Non starter
The elearn from fiat posted by @Communicator is correct.
The rev counter can be an indication of crank sensor failure depending on how the rev counter functions but is not infallible. I do not know why rev counter not functioning.
You could measure ac volts between the crank sensor signal wires at the ecu connector engine cranking to check your new sensor.
You could see if your old crank sensor is magnetic if you still have it.
With ecu plug disconnect . Check the resistance between the connectors in plug for the crank sensor, the resistance should be the same as a new crank sensor. If open circuit the there is a break in the crank sensor circuit.
The crank sensor provides a voltage signal to the ecu . The sensor is "dumb" and does not require any power or voltage from the ecu. So you would not expect a particular voltage at the ecu side of crank sensor wiring.
The only way you would know if the voltage you are reading for the crank wires at the ecu is normal or not is test an identical working ecu.
Test the resistance of the crank sensor at disconnected ecu plug .
I'm back, like a bad penny, sorry been away,
I sent the ecu to ECU testing, just had a email to say they do not have the equipment to test it.
Please can some one recommend a repair place the can test and repair the ECU
I sent the ecu to ECU testing, just had a email to say they do not have the equipment to test it.
Please can some one recommend a repair place the can test and repair the ECU
Mike1alike
Established member
When I needed to repair the ECU I saw this place that looked legit to me:
www.actronics.co.uk
As I got another SH good ECU, I didn't get to send mine and see if they really do the repairs.
Contact Page | Get In Touch - ACTRONICS LTD
Do you have a question for us? Please contact our customer service via e-mail or phone.
www.actronics.co.uk
Mike1alike
Established member
Also this one, the same:
Hi jackwhoo, Just read your last post, thanks, the crank sensor that i have is a three wire sensor, red power from ecu 5v black earth and white signal form crank sensor to the ecu.
But as i have said i only have 2.5v from the ecu
I might be wrong but i think you are taking about a two wire crank sensor
But as i have said i only have 2.5v from the ecu
I might be wrong but i think you are taking about a two wire crank sensor
Communicator
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Perhaps I have said this before? In my understanding the crank sensor is a 2 wire device, with a screened cable. That is what the lower RHS corner of the attached diagram suggests to me. How about Red & White = signal to ECU, Black = screen to earth via ECU?
Eternal Optimist
Member
I had great service from this place...
ECU Doctor.
They even supplied me with an ECU cloned to my vehicle for trial purposes - for a charge, obvs.
Communicator, thanks for the reply, but please if possible tell me why i have 2.5v coming out of the ecu going to the crank senser and ECU tuning has a youtube video saying that it is 5v coming out of the ecu
as you can see i am confused
Eternal, thanks, i will phone them
as you can see i am confused
Eternal, thanks, i will phone them
Communicator
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If as I suspect the ECU port is just an input connection, you would be seeing an internal biasing voltage via a high resistance. Your meter could be less sensitive than that used on Utube. This would result in a lower reading. Perhaps some research into the Bosch crankshaft sensor would resolve your conundrum.
Mike1alike
Established member
Good thing about the ECU. Who did the repairing? Put their details here, might be of help to others.
What does it mean "the fuel pour's out of the pipe feeding the high pressure pump"? Is there a hole in the pipe or is it pouring back in the tank? Is the pressurestat faulty, maybe?
What does it mean "the fuel pour's out of the pipe feeding the high pressure pump"? Is there a hole in the pipe or is it pouring back in the tank? Is the pressurestat faulty, maybe?
Sorry did not explain it very well,
No i do not have a leak in the pipe.
when the ignition is turned on the low pressure pump is feeding the high pressure pump, so no problem with the low pressure side
What i do not have is fuel rail pressure, ie high pressure
What i would like to know is what stops the pump suppling the high side to the fuel rail
It starts with easy start so the gear is tuning the fuel pump, cam belt ok
ECU testing by ECU express
No i do not have a leak in the pipe.
when the ignition is turned on the low pressure pump is feeding the high pressure pump, so no problem with the low pressure side
What i do not have is fuel rail pressure, ie high pressure
What i would like to know is what stops the pump suppling the high side to the fuel rail
It starts with easy start so the gear is tuning the fuel pump, cam belt ok
ECU testing by ECU express
Mike1alike
Established member
I don't know exactly if your model has on, but usually on Fiat there is one next to the fuel pump, in the tank. When pressure gets to high, it opens up and lets fuel go back in the tank, no need for return fuel line this way and pressure is constant. But you say that part (low pressure) has fuel on, so it's something else on yours.
For the high pressure fuel pump, if there is something wrong with it I'd say you need to contact specialists on this domain as it is very sensitive and not to mess with.
However, you can check the electrical line that feeds it, if it has one.
Hope some other colleagues here can be more helpful.
For the high pressure fuel pump, if there is something wrong with it I'd say you need to contact specialists on this domain as it is very sensitive and not to mess with.
However, you can check the electrical line that feeds it, if it has one.
Hope some other colleagues here can be more helpful.
Eternal Optimist
Member
I had similar once with a Vivaro. There was an invisible break in the cable which was within the insulation.
I only discovered it when I dropped a spanner, which hit one of the cables to the fuel rail pressure sensor. At that stage the cable insulation snapped, revealing the problem.
So I'd suggest in the first instance you locate the fuel pressure sensor on the rail and check it's getting the required voltage.I don't know what that should be - although I suspect @Communicator will - but on the Vivaro it was 5 volts.
I only discovered it when I dropped a spanner, which hit one of the cables to the fuel rail pressure sensor. At that stage the cable insulation snapped, revealing the problem.
So I'd suggest in the first instance you locate the fuel pressure sensor on the rail and check it's getting the required voltage.I don't know what that should be - although I suspect @Communicator will - but on the Vivaro it was 5 volts.
