Fault 2900 and 135f

[5cilinder]

Originally Posted by osullivant

Thanks for the replies todate,

The Sensor code appears immediately on switching on the car and cannot be cleared. whilst the maf fault only appears after the car has ran for a while, my current thoughts are that there is a leak in the system causing the maf to complain I will explore this in more detail tomorrow or the day after.

as for the fuel sensor, I checcked wiring back to the ecu plug and all seem to be fine, I removed the sensor and it has 23ohms accross the two outside pins the middle pin seems connected to nothing and none of the pins seem to be connected to the body of the sensor. I cannot check it in position because of the restrictions in space, to do so I would need to cut the loom or find a connection on a scrap car to fit.

Question , does the fault code indicate a failed sensor or a good sensor reading an unacceptable amount of pressure.?

I would like to double check if the sensor is duff before I pay for a new one...

regards,

Tony.

ill look up the 23 ohms
It will help if you get torque and elm 237 to readout live fuelpressure data while driving to see if there are unacceptable high or low values

The 2900 code implies a faulty sensor or wiring

[osullivant]

Thanks.

Yes I think it must be the sensor or the ecu as it is not the wiring and it is always present. if it was something else such as the fuel pump it would be cleared and not return until the engine was running.

I do not have access to elm 237 but I have another code reader which I think gives live data, what pressure should I expect.?

Tony.

[5cilinder]

Thats not completly true for all sensors , sometimes drivecycles are required to clear the fault. (this sensor im not sure)

Pressure at idle is 350 bar and full throttle between 2000 and 3000 rpm 1600 bar
Normal driving its arround 500 600 bar

[osullivant]

I tried my other scanner and it does not show any information about fuel pressure.

Whilst we were getting the car to start after putting it together it refused to start for a long time because we had neglected to connect the injectors.... later following connecting all 5 it refused to start and I suspected a fuel blockage but when I opened the fuelline there was tremendous pressure . I wonder did this repeatedly trying to start cause the sensor fault.
In any case the car started right away after releasing the pressure so perhaps I damaged the sensor at that stage.

tomorrow I intend to remove the sensor, run the fuel pump and see is there an obstruction in the rail and also clean the sensor and leave it in some warm water to allow it to rest in case some diaphram or spring is depressed/stuck. if that does not work and if no further suggestions are received I will just have to buy a new sensor at the main dealers on Monday,

[cheshired5]

Originally Posted by osullivant

if no further suggestions are received I will just have to buy a new sensor at the main dealers on Monday,

You haven't bought a £5 ELM327 but you're prepared to buy a pressure sensor from a main dealer based on a guess?
Why?

I'm not saying the sensor isn't faulty but it's arguably the least likely cause of your problem and it's easy to check with cheap diagnostics.
Even if the sensor was the culprit, replace it with one from a breakers.
They're dirt cheap from there because there's no demand because they hardly ever fail.

[5cilinder]

Originally Posted by osullivant

I tried my other scanner and it does not show any information about fuel pressure.

Whilst we were getting the car to start after putting it together it refused to start for a long time because we had neglected to connect the injectors.... later following connecting all 5 it refused to start and I suspected a fuel blockage but when I opened the fuelline there was tremendous pressure . I wonder did this repeatedly trying to start cause the sensor fault.
In any case the car started right away after releasing the pressure so perhaps I damaged the sensor at that stage.

tomorrow I intend to remove the sensor, run the fuel pump and see is there an obstruction in the rail and also clean the sensor and leave it in some warm water to allow it to rest in case some diaphram or spring is depressed/stuck. if that does not work and if no further suggestions are received I will just have to buy a new sensor at the main dealers on Monday,

You cant just opening fuellines before you know the pressure is gone , you do know that with high pressures the diesel kan be blown through the skin an come in the bloodstream and threaten your life .
What rob said buy a cheap elm 237 first, maybe its not the sensor afterall but just a plugged fuelfilter or pump/injector wear

[osullivant]

Originally Posted by 5cilinder

You cant just opening fuellines before you know the pressure is gone , you do know that with high pressures the diesel kan be blown through the skin an come in the bloodstream and threaten your life

Thanks for the warning, but i do understand the dangers of high pressure and releasing it safely. and keeping fingers and eyes away.

[cheshired5]

Originally Posted by osullivant

Thanks for the warning, but i do understand the dangers of high pressure

Excellent..
Do you also understand that parts changing based on a guess is the worst and most expensive way to fix a car?

[osullivant]

Originally Posted by cheshired5

You haven't bought a £5 ELM327 but you're prepared to buy a pressure sensor from a main dealer based on a guess?
Why?

I'm not saying the sensor isn't faulty but it's arguably the least likely cause of your problem and it's easy to check with cheap diagnostics.
Even if the sensor was the culprit, replace it with one from a breakers.
They're dirt cheap from there because there's no demand because they hardly ever fail.

ELM 237s are not readily available in my locality. I would need to wait possibly a week to get one. In any case I doubt that any diagnostics other than a volvo set up can tell me if the actual sensor is misbehaving as there is nowhere else to obtain a comparative reading!

Breakers who may have sensors in my part of the world are few and far between, none that I called on saturday had a sensor.

Buying a used one on line could cost me as much given the rip off postal and packing rates quoted by some suppliers and I might get a duff one.

From the list here.....http://forums.swedespeed.com/showthr...onversion-List ......it seems that it is more likely a bad sensor rather than an unacceptable level of pressure caused by another problem.

My decision to buy the sensor is hardly made on a guess.

I would happily pay a fiver for an elm or buy a sensor for dirt cheap money but neither is an option right now, I need to get the car back on the road, I need to get my hands clean and get some work done this week....

Tony.

[osullivant]

Originally Posted by 5cilinder

Thats not completly true for all sensors , sometimes drivecycles are required to clear the fault. (this sensor im not sure)

Pressure at idle is 350 bar and full throttle between 2000 and 3000 rpm 1600 bar
Normal driving its arround 500 600 bar

My thoughts on this have changed, having discovered the price as the main dealers for these two sensors...... 500 euros... or 10% of cost of car.

I have tried a different fuel pressure sensor which is identical to the original except the number is 1 digit different. 0281002706 instead of 0281002707. my original is working fine in the car that donated the second sensor so I am pretty sure that the sensor is not not faulty.

I also got hold of an ELM 237 and torque lite but I cannot get it to display any fuel pressure readings.

I still have a MAF problem and cannot get a replacement except new but I have a maf reading at idle of 15.5 rising as the revs increase.

does anyone have suggestions what to do as regards using torque to diagnose the faults or what to do if it is not the sensors.

Tony.