Hi all, ive got a bit of a problem with my 2.1 zetec turbo,
I've hit a problem and cannot sort it, basically ive been having running issues due to what I though was a leaking injector, so I got a replacement, fitting it and it's still leaking.
So I swapped the leaking one* (no1 injector) for one that wasn't (no4 injector) but still the leak was on no1 cylinder....which indicated to me that it had nothing to do with the injector.
I then took the fuel rail out and noticed a very small chunk out if where the bottom oring sits on the injectHor seating, so I bought a new fuel rail checked it over, no marks what so ever and I fitted it today, turned ignition on and its still leaking on the same one!! So I then took the aftermarket injector out and put a standard one in but it's still leaking!! I honestly haven't got a clue what it could be?? And it's not to do with the wiring as the wiring isn't plugged in when it's leaking so it's got to be something else,
I can't think where else fuel can get into the cylinder with out passing through the injector or leaking through the bottom oring, I have even tried a thicker oring to maybe make a better seal but never worked.

I'm using the efi HO inlet manifold and fuel rail ect
I have an up rated fuel pump aswell and I am now thinking there might be too much pressure in the fuel rail causing the fuel to push through the bottom o-ring ?
Any help or suggestions would be great cheers

Sounds like too much pressure as you may think.

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Yea could be just needed a few more ideas of what it could be, can I adjust the voltage on the fuel pump via my omex to lower the pressure or have I got to get an adjustable fuel pressure regulator to do that ?

Voltage wouldn't necessarily adjust the pressure. You could try it of course though, no harm in it.

The only downside to a pressure regulator is they are good until too much pressure builds up and another type of seal gives way, plus also when you need as much fuel as possible on full boost it might not be able to supply it - that can be the same with the voltage too... By the sounds of it you are running with a fuel pump that is giving out more pressure than you need, maybe it might be worth downgrading? As long as the lesser model pump is adequate enough to supply enough fuel then its all good.

You could get really technical and perhaps program the ECU to give less voltage to the pump at lower rpm/boost and then more at higher boost, that could solve the problem if you are able to do that.

Different setups work differently of course.

Also, I presume the fuel return line isn't crimped anywhere restricting flow back to the tank? Just thought about that.

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I just went out to check that and there aren't any kinks but I'll double that when I get some good weather and not dark lol, I'll try putting my old fuel pump on on the weekend just to see if it is too much pressure and I'll try find out if I can adjust the voltage or watever on the pump via the omex if it is too much pressure causing it, thanks buddy

are you still running the standard fuel pressure regulator in the fuel rail? have you actually checked the fuel pressure? have you changed the pump and then the problem start? could be excessive pressure due to the regulator or return pipework restricting flow. i use a 255lph uprated fuel pump with a separate FSE Fuel pressure regulator and the standard Si pipework seems to cope with it ok. The aftermarket ECU (mine has a Emerald ECU) generally has no control over the pump pressure generated, they just give a pump run signal via a relay, pressure controlled just by the regulator.
you really need to find out what fuel pressure the engine was mapped on and stick to it especially if fitting a aftermarket adjustable one unless you are having it remapped? as the ECU will be programmed to open the injector of a specific time dependant on the revs/load/boost map, if you vary the fuel pressure without adjusting the injector opening time it will adjust the mixture eg same injector time at lower pressure = less fuel- lean mixture, higher pressure rich mixture

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Will

Hi will yes I am using standard fuel pressure regulator for now but intend to pus a cosworth one on to allow for more fuel when on full boost, I have checked the fuel pressure and there is none at all because of the leak, the leak is even there when the wiring is unplugged from the injector so it's nothing to do with the map, I'm going to check all the return hose all the way back to the tank just to make sure

Where are you taking the fuel pressure from? with the pump running would expect about 3 bar on a NA zetec, leak should'nt really drop fuel rail pressure (unless really bad and more than pump flow) as regulator is on return after the leak

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Will

From the attachment on the fuel rail I'll try it again see what reading I get with a different tester the one I used could have been faulty

Fixed it! Turns out it was all 4 injectors leaking but the fuel was only going into no1 cylinder not all 4 :s
All I did was take the fuel rail out, kept the fuel line attached, turned ignition on and petrol was coming out of all 4 injectors so I put the o-rings off the standard injectors on the other ones and job done no more leaks!
Thanks for the help

not sure if this is completely related, but my zetec turbo runs skyline injects rb25det ones 375cc iirc,
i fitted them in the standard rail with zetec o-rings and they split whist mapping and leaked massively,
I ended up buying some brand new skyline injector rings (top and bottom seals) and fitting them using breakfluid as a lubricant and have had no problems since,

(the next morning after they split the car wouldn't start start and completely bore washed all cylinders topping up the oil with about a litre of petrol,

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buttery biscuit boost