Morning all.

Can any body help me with fuel rail pressure . The K series 1800 needs approx 3bar, I have used a 3 bar rated pump but are having big issues with running and starting the AFR is about 17 , which is obviously very weak , I have checked the lot and can only assume that I do not have enough flow / pressure coming from the pump. I feel that if the fuel reg is 3 bar, I should have bought say a 5 bar pump, which would then let the system run with plenty in hand? Any thoughts on this gratefully received as always. Have done a flow test from the pump to the fuel rail and all flowing ok.

[Edited on 16/1/16 by Mikef]

[Edited on 16/1/16 by Mikef]

Normally fuel pressure is determind by the regualtor not the pump. Although your pump appears on the low side at this stage I don't think it is the problem
First some questions.
Which model did the engine come from ? The Rover 75 and MG ZT 1.8/ models usee a different returnless fuel system, the fuel rail looks the same but the return pipe connection is a dead end, and the regulator in the fuel rail is replaced by pulse damper which looks identical to the earlier part.

If you using an engine from a non-75 or non-ZT you should use the standard pressure regulator in the fuel rail with a return pipe

Rover MEMS is a very reliable system but it relies heavily the MAP and temperature sensors once the engine warms up and the system goes closed loop and getting signals from the upstream lambda sensor (B1S1) the fuel trim range is wide enough to correct major variations in fuel pressure.
The MEMS system is however notoriously picky about the lambda sensors used it will generate a fault code with many aftermarket Lambda sensors however NTK (NGK) or Fuel Parts sensors are fine if the are genuine.

Because of the cold start issue I would make the coolant temperature first, I would back pin the connectors at both the sensor and the ecu and check the resistance correct and has got good connections back to the ecu socket?
The MAP sensor output also needs looked at.

I have assumed you have checked for vacuum leaks?

Having something that will talk to the MEMS system to get live data helps a lot.
There is an advanced diagnostic interface and software available PScan will talk to all versions of the MEMs and other Rover moxules for about £170

Hi,

The pump should be able to produce a lot more than 3 bar. If you dead head the pump (block the supply pipe with no regulator) it should be able to produce 8 to 10 Bar.

What pump was it? Do you have a link?

Thanks for the replys. I spent quite a bit of time on this yesterday and I am still no further on. Except that I have done a lot more std checks on things like compression test, just to make sure, air leaks, injectors, crank sensor , TPS . I do not have a fuel rail pressure gauge but I think my next step is to get one and check the static pressure and the pressure when running. The one thing that I think is an indicator of something is that 3 and 4 just about run (hot exhaust manifold ) 2 seems to be running with a few pops and bangs (warm exhaust ), number 4 is not running at all (cold exhaust). I have checked for a spark it is a wasted spark so if there was an issue 3 and 4 would not run as they are not fired together.I have also tried a different map in case that was an issue , still the same.

Wasted spark normally fires cylinders 1 and 4 together and 2 and 3 together, check your firing order.
Sorry just retread your post , i

[Edited on 17/1/16 by rusty nuts]

sorry for that panic starting to set in.Have checked spark and it is fine.

Just thought if you have a Ford ignition 4 tower coil pack Ford firing order is 1243 Rover Firing order is 1342.

I still suspect the O2 sensor reporting lean is due to the misfire (False Lean) rather than the other way around.

False Lean Quote pasted from lambdapower.co.uk website

quote "One thing to keep in mind about wideband O2 sensors is that they can be fooled in the same way as a conventional oxygen sensor by air leaks between the exhaust manifold and head, and by misfires that allow unburned oxygen to pass through into the exhaust. Either will cause the sensor to indicate a false lean condition which, in turn, will cause the computer to make the engine run poorly, idle badly, or fuel constantly rich."

Thanks for all of this, The coil pack is run by an Emerald ECU and was set up to run correctly. I certainly agree about the false lean reading. Its just trying to find the cause of the poor non running. I am certainly leaning towards the pump. I do not know what else I can check or change. Will get a fuel pressure gauge, which I probably should have any way, and check static pressure , although I have swapped the pressure reg. and then the pressure once the engine is turning over and see if it drops below 3 bar.

How did you test the injectors? If you just tested the resistance try swapping the injector from a duff cylinder to a good one , wouldn't be the first duff injector

thanks on the list for tomorrow.

quote:

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Originally posted by rusty nuts
How did you test the injectors? If you just tested the resistance try swapping the injector from a duff cylinder to a good one , wouldn't be the first duff injector

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Injectors can 'stick' if they haven't been used for awhile

Stethoscope is your friend or you can power them up with a battery after a resistance test and checking their receiving voltage in the first place

Good one will give it a try.

A definitive way to test a sticking or blocked fuel injector is to use an injector pulser to do an injector balance test.
After watching a video on the Schrödinger's Box YouTube channel bought a Bergen one identical to the Sealey VS211 it only cost about £40 off eBay.

The other test methods involve an oscilloscope either to look for a hump on the pintle voltage wave form, or using looking at the output of a pressure pulse sensor.

The Schrödinger's Box and ScannerDanner YouTube channels have some good vids on the subject there is also a good but long one on the South Maine Auto Repair channel showing tracking down an injector missfire on a Corvette.

[Edited on 17/1/16 by britishtrident]

I had running problems last year on my injected X flow, cured it by rigging up an in tank pump submerged in a mixture of petrol and injector cleaner feeding into one injector at a time and opening the injector using a push button switch , leads and a battery. If you do likewise make sure you do it well out in the open etc