Cleaning fuel injectors

[househead]

So I wanted to get my injectors clean as I'm unsure if it's ever been done over the lifetime of the car. From what I can tell, getting it professionally done can cost around £70. Not loadsamoney but if I can DIY it, I will

Just watched this video on youtube...

https://www.youtube.com/watch?v=8rk0tKtiVic

... and wondered a few things.

- Anyone done this before? Got any tips?
- Is there any risk of carb cleaner residue being left inside the injectors?
- How can I depressurise the fuel system and ensure there's no fuel in the injectors when I remove them? (watched a video on removal but they didn't cover the depressurising.
- Anyone know what O rings I need to replace the existing ones ... makes sense to if they're as old as the car, right?

[Carolyn]

Don't worry about spilling a little fuel.  Easy enough to mop it up.  There will be very little pressure.

Th O rings are 8mm  ID x 2mm  Viton.

Check Sealforce on Ebay.

I'd just run the tank down and put some good injector cleaner in the tank. (Forte is good but not cheap.) 

[househead]

Thanks @Carolyn

[jvanzyl]

I think I put a few comments on changing injectors in my thread..

You want a vacuum cleaner with a thinner bit of tubing attached to it via tape to suck up all the debris that is usually around the area.

Just use a rag for the extra fuel and enjoy the smell.... erm was that out loud?

Anyway, get a light source and be prepared to film with your phone and use a mirror to get things in and out gracefully.

don't forget to be gentle with all the screws as the plastic that is holding down stuff is approaching kinda brittle. 

Other than that, I used simtek to clean injectors last time round..

[househead]

I think most of us enjoy that smell! Just wanted to avoid a squirt in the eye, mostly!

Thanks for heads-ups mate!

[Carolyn]

Oh.

And put a smear of engine oil on the O rings when you are ready to pop the injectors back into the fuel rail.

[james_ly]

Er... do injectors need cleaning? 110k miles here, smooth as any car I've driven.

[Joesson]

I think I put a few comments on changing injectors in my thread..

You want a vacuum cleaner with a thinner bit of tubing attached to it via tape to suck up all the debris that is usually around the area.

Just use a rag for the extra fuel and enjoy the smell.... erm was that out loud?

Anyway, get a light source and be prepared to film with your phone and use a mirror to get things in and out gracefully.

don't forget to be gentle with all the screws as the plastic that is holding down stuff is approaching kinda brittle. 

Other than that, I used simtek to clean injectors last time round..

@jvanzyl and @househead

Johns suggesting of using a vacuum cleaner to remove (DRY) "debris" I suggest is valid but do NOT use if fuel present!

[Petrus]

Johns suggesting of using a vacuum cleaner to remove (DRY) "debris" I suggest is valid but do NOT use if fuel present!

Great fun though, if a bit risky, converting the vacuum cleaner in a flame thrower :-)

[thetyrant]

Ive always just sent mine off to be done professionally then i know its right and it doesnt cost much, yesterday i sent off the ones that came with my turbo kit to be cleaned and flow tested down at APT tuning who i have used before, 2 main reasons with 1 i want them to be 100% right as it more critical with forced induction, and 2 ive no idea what size they are so they will be able to tell me once they test them, to me its just not worth risking leaning out with a dodgy injector for what it costs to get them cleaned and checked.

Generally with modern fuels injectors dont have issues these days but if you run cheap fuel it can be an issue, or if car sits for long periods of time unused the fuel can varnish up and block the injectors, holes in the injector nozzle  are very small so doesnt take much to cause a problem and a proper ultrasonic clean is only way, sometimes its not even possible to get them 100% again.


Edit to add, just watched that video what a load of crap, no different to just running them in the car reallym  if there is an issue with the injectors you need to put them in ultrasonic bath to get them cleaned, squirting carb cleaner through at low pressure from aerosol will do bugger all imo

[househead]

Johns suggesting of using a vacuum cleaner to remove (DRY) "debris" I suggest is valid but do NOT use if fuel present!

Great fun though, if a bit risky, converting the vacuum cleaner in a flame thrower :-)

I've got some cans of compressed air, should do the trick and probably a bit safer!

[househead]

Er... do injectors need cleaning? 110k miles here, smooth as any car I've driven.

I guess I'm being proactive. I don't know they need cleaning, but I do know that if done right that cleaning them won't hurt and would mitigate them becoming clogged or dirty in the near future.

I know for a fact that during its life this car has for at least some of its previous 8 owners been a summer car and therefore likely been left for long periods unused and with fuel in the system.

[househead]

Edit to add, just watched that video what a load of crap, no different to just running them in the car reallym  if there is an issue with the injectors you need to put them in ultrasonic bath to get them cleaned, squirting carb cleaner through at low pressure from aerosol will do bugger all imo

The main difference I can see would be the opportunity to see and inspect them as well as cleaning them and also to replace the O ring seals.

Edit: oh and also I get to see another part of my car and how it comes off and goes back on... this is quite valuable to me!

I actually have an ultrasonic bath, but I wouldn't put them in there as firstly I wouldn't know what liquid makeup to use and secondly I can't see how a standard ultrasonic bath on its own would help ... you'd be dislodging dirt inside a closed space therefore you'd still need to push that out somehow. Not to mention that you'd need your cleaning liquid inside and outside the injector during the bath for it to be of any use

[thetyrant]

Removing them for the sake of it if car is running sweetly is a bit of a waste of time really, but I appreciate where you coming from finding out how things come apart etc.

Visual inspection of the injectors doesn't tell you much and certainly no indication of how they are functioning so that is pointless unless you have a leak or other issue, to actually check them you need to hook them up fuel/cleaner supplied at correct pressure (approx. 43psi is the norm) and pulse them to check the spray pattern and flow rates, checking that they all flow the same amount etc which like cylinder compression testing is just as important as the numbers themselves.

If spray pattern is poor or flow rate not in spec/uneven between each in set then ultrasonic cleaning while pulsing them is how you clean them properly, if the spray pattern is good and flow rate correct no need to do anything, fit new seals and refit carefully.

They a bit fiddly to access on these cars due to location so hence taking them out for a look I wouldn't really recommend unless you have problem and suspect they are cause.

[thetyrant]

Here is a better video on checking and cleaning etc - https://www.youtube.com/watch?v=ZJmdvoZ83hY

[househead]

Thanks for the tips!

I will reconsider sending them off for cleaning (or just leaving them in and doing it via the tank!)

[Carolyn]

Your engine is running sweet.  Don't groom a working horse.

[Beachbum957]

Your engine is running sweet.  Don't groom a working horse.

Absolutely agree.

But if you feel you must use a fuel injection cleaner, pick one that does more than lighten your wallet.

How to Pick a Fuel Additive That Works

Fuel system cleaners that contain PEA like Chevron Techron do seem to work.