Author Topic: Remove / replace fuel injectors (1.8T)  (Read 11682 times)

Offline Mr_Orange

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Remove / replace fuel injectors (1.8T)
« on: 11 April 2010, 15:12 »
Remove / replace fuel injectors on a 1.8T

This is a dangerous system of the vehicle.  Be aware of the potential hazards in doing this!
You will be handling petrol.
Work in a well ventilated area.
Do not do this on a red hot car for the obvious reasons.
Ensure you disconnect the correct fuse and battery when suggested.  Fuel pressure must be released to carry this work out.  You really don't want 3bar petrol anywhere near your skin or eyes.
Do not get any contaminants inside the manifold or the fuel rail.

Tools required:
Needle nose pliers
Flat bladed screwdriver
5mm allen-key driver on a slim extension
Rags
Safety specs
Fire extinguisher
Chocolate digestives

Locate fuse #28 (fuel pump 3rd up from bottom on right hand side)
Fire up engine, remove fuse and engine will die (this removes fuel pressure from lines and fuel rail)
Remove engine covers
Disconnect battery negative and make sure battery lead is well away from any points of contact (no sparks!)
Try and clean around the injectors a bit, they will be manky and you don't want debris falling inside the manifold.
Release 4x terminal connectors to top of injectors
Using screwdriver waggle plastic carriers off fuel rail to access 2 x bolts holding fuel rail down.  Undo and recover these short bolts (fiddly).
If possible its easier if you disconnect the two fuel pipes into the rail to get it fully out of the engine bay.  However you can do it without removing from engine bay like I did.
Remove vac line from fuel pressure regulator at end of fuel rail.
Gently pull fuel rail up and outwards, twist over to point injectors towards car.  Fuel rail comes away very easy.  Orientate the rail on top of the injector wiring.
Cover injector ports with a length of rag to stop anything falling into manifold (that would be VERY bad).

Now the fiddly, fun, fuel covered bit:
Using pliers remove the clip holding one of the injectors on.  I started with injector at the battery side will explain in a mo...
Position another rag to catch the bit of fuel that will come out
Turn injector around a bit to loosen seal then try pulling it out straight, this is more difficult than I thought.  They come out eventually but with some massive tugging.
Wait for fuel to stop dripping from rail. Position rag and tip it up a bit to pour the contents of the rail out of that injector hole.  You will get a "reasonable" amount come out.
Recover seal from rail if its popped off injector.
Repeat for remaining injectors.  With fuel lines left on this is a pain, but I couldn't pull pipes off so managed with rail still attached.

Being super careful I cleaned the injector seats to remove any potential guff that might fall into the manifold, I also gave the injector seats on the rail a rub to remove any minor stuff that might get pushed in.

I then immediately replaced the injectors with a set I'd had refurbed (@ Mr Injector UK).

Refit is reversal of removal, noting:
>Don't get any dirt etc in the manifold or the fuel rail when re-assembling.
>Be gentle with the injector loom as the cabling is fairly fine and could easily be damaged.
>Make sure the metal clips fit back onto the injectors properly.  Once fitted I gave them each a wiggle/spin to ensure the correct engagement.  Don't want these popping off!
>The two bolts are all that's holding this lot into the manifold.  They were a pain to refit as had to be aligned to the fuel rail and also brackets for the return pipes to charcoal canister.  They want to be tight but don't over-tighten as they are only mounted in the soft aluminium manifold.
>Replace vacuum hose onto the fuel pressure regulator.
>Remove all your petrol soaked rags and tools.  I left the bonnet open for a mo to let any fumes vent away.

With fuse replaced and battery reconnected, the car took a moment to fire up after it had re-pressurised the system.  After verifying it runs and all went back together correctly, turn it off and leave bonnet open for a while to make sure any petrol fumes are fully dispersed before getting engine hot.



This was performed on a 2000 (X) AUM.  A similar procedure would apply on other petrol engine types.

Absolutely no responsibility taken for anyone attempting this and ending up toast
« Last Edit: 30 June 2010, 17:27 by Mr_Orange »


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Offline T_J_G

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Re: Remove / replace fuel injectors (1.8T)
« Reply #1 on: 11 April 2010, 16:06 »
Probably worth adding where you got them refurbed. I'll add what pics I got when I get a chance.