2.3 DOHC fuel pump failure

[philcoyle]

Re: 2.3 DOHC fuel pump failure

I think the question was asked, what have other owners done to replace their failed pumps. The only sensible reply came from Dave Clutterbuck who suggest Droverpete replace it with OTP019 pump from info I gave him and he fitted, this unit is rated at 3 bar -5 bar, 5bar being higher than 3bar.
I have missed out on a lot of technical info whilst recuperating it seems, so could someone fill me in on what part the ECU plays in an EFi setup and how it is connected to the fuel pump.
What is a 15 to1 air to fuel ratio.
How is this achieved .
How do the injectors know when to open and how much to deliver.
How does a fuel rail maintain 3bar pressure.
What's a fuel pressure regulator what controls it.
Does an EFi fuel pump, pump faster if the engine is being driven hard and can therefore vary its pumping rate, if so how is this controlled.
And can someone come up with a part number for a fuel pump for Droverpete which is the question asked in the first place.
Answers on a post card to inosumfing.co
Looking forward to all knowledgeable info.
By the way Droverpete take your pick up pipe out and check the filter, you know it makes sense.

[scott h]

Re: 2.3 DOHC fuel pump failure

I can tell you how the EFI works on my Vauxhall red top.

The injectors supply a fixed rate of flow when opened. The amount of fuel supplied is varied by the length of time the injector is opened. The injectors are connected to a fuel rail, which is a pipe reservoir full of fuel at high pressure. This fuel rail is supplied by a high pressure pump, which runs at a set speed. The pressure in the rail is kept within set limits by the fuel pressure regulator. This is a relief valve which opens at a set pressure and sends excess fuel out of an overflow. The overflow is connected to a swirl pot from where the high pressure pump feeds. The swirl pot is supplied by a low pressure pump at the tank. There is an overflow back to the tank so that the swirl pot is always full.

The injectors and the ignition are controlled by the ECU. It takes readings from lots of sensors such as throttle position, intake air temp and flow, a knock (pinking) sensor etc. There is also a sensor in the exhaust to measure the composition of the gasses. This is how it can determine the air to fuel ratio, and aim for the 15 to 1 which is the correct chemical ratio for complete combustion.

[ggrum]

Re: 2.3 DOHC fuel pump failure

As far as I know, this is pretty much the same as with the 2.0l Ford DOHC engine. The fuel rail is maintained at a constant pressure by the pump and the length of each electrical pulse to the injectors determines the amount of fuel injected. This is computed by the ECC IV module depending upon parameters determined by the various sensors on the engine and exhaust system.

[philcoyle]

Re: 2.3 DOHC fuel pump failure

thanks Scott h,
the fuel pressure regulator does indeed maintain the fuel rail pressure at a constant pressure of about 3 bar or 3x14.7psi.
This constant pressure and the length of time the injector is open gives the precise amount of fuel to achieve 15 to1 ratio. The Lambda sensor in the exhaust feeds info back to the ECU which modifies injector opening times to maintain the correct fuel ratio.
All we have to do know is wait for a fuel pump part number.
Phil

this may help http://www.fuelpumpsonline.co.uk/syt...019-1930-p.asp
or this http://www.fuelpumpsonline.co.uk/bos...edes-172-p.asp

[scott h]

Re: 2.3 DOHC fuel pump failure

Following on from my previous post about EFI. The ECU reads all the sensors many times a second. It then refers to a stored set of instructions to decide when and how long the injectors should open, and when the ignition should trigger a spark.

This stored set of instructions is known as the map. When an ECU is remapped it means these instructions have been changed. Sometimes the information cannot be changed, this is when the chip containing the information is changed. This is known as chipping.

[peterboat]

Re: 2.3 DOHC fuel pump failure

thanks Scott h,
the fuel pressure regulator does indeed maintain the fuel rail pressure at a constant pressure of about 3 bar or 3x14.7psi.
This constant pressure and the length of time the injector is open gives the precise amount of fuel to achieve 15 to1 ratio. The Lambda sensor in the exhaust feeds info back to the ECU which modifies injector opening times to maintain the correct fuel ratio.
All we have to do know is wait for a fuel pump part number.
Phil

this may help http://www.fuelpumpsonline.co.uk/syt...019-1930-p.asp
or this http://www.fuelpumpsonline.co.uk/bos...edes-172-p.asp

Bit expensive I prefer my £24 jobby works well and is reasuringly noisy but has a 2 year warranty so I couldnt care less