Replacing Injector

[Tricky69]

I had an error code re number 4 injector, cleared it, travelled 600+ miles to/from Wales and the same error code has popped up. I have now decided to replace number 4 injector (now purchased one off eBay) and replace all the injector seals while I am at it.

The question is, can I simply change one injector for another or does it need to be reprogrammed anywhere? It is a like for like replacement, but not sure if it is a straight forward swap.

Cheers.

[Tricky69]

Forgot to mention it is a diesel injector!

[Chrispb]

What was the error code?
It's more common for the injector wiring loom to be the problem.

[johnnyroper]

As above most likely the wiring loom causing the problem they get poor connection with solenoid when they age.

So long as it's correct injector for your engine it is straight swap.

However you will need to replace the 4 hold down bolts and align the injectors if you replace all the seals. Supposed to use big caliper gauge but I found using feelers in gap between solenoid block and head before removal ensured I got injectors back in perpendicular.
You will also need new rocker shaft bolts and have to set up injector stop screw.

If you go down injector and seals change I have the vw seal fitting tools you can borrow for postage cost as it's very easy to damage them without it.

[johnnyroper]

Some info on injector change/set up

https://www.darksidedevelopments.co.uk/account.php?action=download_item&data=ODIzODQsNjgzLDQwNjkyLGMzZjJjODFkYzFlMGY5ODc2OTZjZDFhMWUwZDkxZWQ1LDQxLDkxMjg0Njk2NTc4Mjc0ODQ4NDIwMzI2MzAzNzQzOTM5MDI2OQ==

I also didn't use a dti when setting up the stop adjustment I did it by eye.

[Tricky69]

Cheers for the replies, guys.

I have a feeling it is an injector as opposed to wiring as when driving slow, it now tends to judder a bit in low revs which it didn't used to do. Simply resolved by dropping down a gear and keeping revs a bit higher, but not in line with my style of driving!

MPG wise it isn't too great - roughly 30mpg for school runs and on motorway around 70mph it was only returning around 36mpg. A previous TDI Galaxy used to do around 48mpg on the motorway!

[johnnyroper]

The wiring loom gives much the same problem as injector fault and is certainly easier and cheaper to replace.

It's more common than injector problems aswell.

[insanitybeard]

As per the other replies worth looking at the wiring loom first- here is an example thread outlining typical symptoms of issues with said loom, and replacement of it is covered here.

[Tricky69]

Okey dokey, done some work on it today!

Replaced the injector wiring section with a new one.

Replaced injectors 3 + 4.

Replaced all the rubber seals on all 4 injectors.

A couple of the injectors were a pig to get out, but most surprising was that injector number 1 was actually quite loose and could be removed by hand.

Took it for a test drive and waheey, instant power, revs freely, no strong smell from the exhaust, no smoke and pulls very strong indeed.

The other week I replaced a driveshaft, tyres and drop links, so now the beast is running very well indeed. Just need to wash it now!

[steveo59]

Hi Tricky69,
Glad you've got it sorted. After having removed the injectors do you feel it was an electrical connection problem or just gunked up so the spray pattern was incorrect or something else? It just helps the rest of us if we have a similar problem in the future.

[Tricky69]

Hi Steveo,

I am in two minds! I am pleased I did remove the injectors and replace the rubber O ring seals as a few of them were hard and brittle. I also noted that injectors 2, 3 and 4 were pretty hard to remove, whereas injector 1 I could remove by hand and was not seated at the right angle, which clearly would have affected it.

A few days in I can say that mpg has improved by approx 7 to 8 mpg for short, around town driving.

Downside is that I replaced the rocker cover gasket with a new one - which leaks oil onto the manifold and needs sorting! I also note that injector 4 is showing a larger quantity on the reading 23 on VAGcom, so may change this one to another.

More to follow!

[Tricky69]

Forgot to mention, while stripping parts down I noticed the cam shaft was worn and a little pitted on the lobes. Oh goody, another job to do in the future!!

[johnnyroper]

Worn camshaft will not help with the injection values,quite expensive to do can as lifters and bolts will also need replacing.