Injector cleaning D5 185

[jtaw45]

I'm looking to find out if there's a way to make a closed loop fuel system to flush the injectors on my car. I wish to run neat Liqui Moly Diesel purge through the injectors to give them a thorough clean.

I did this on a previous XC90 163bhp with amazing results but the fuel system is different on the 185.

I'm not interested in cleaners you add to your fuel or filling the filter housing with neat fluid as it just gets diluted down to beyond anything even remotely beneficial in my opinion.

The closed loop I used before was definitely the way to go but not sure it's possible on the 185 due to it relying on a stronger fuel pump at the rear of the car as opposed to the 163bhp which would just suck the fuel out of a jar in the engine compartment.

[colinbos]

I understand this has been tried and it was a No.

[Zchas13]

I too have been wondering about how to do this.

I've not done it, but was wondering why no-one has suggested waiting til the tank is virtually dry, adding the moly into the diesel tank then and running it til it stops?

The concentration of cleaner would be greatest this way and no fancy interruptions of the fuel lines would be needed. As far as I'm aware the car will restart after a few turns of the key as the pumps prime the system don't they?

I've read that you should probably change the fuel filter after cleaning?

Not an expert by the way and am expecting to hear that this would be a bad idea for some reason?

[colinbos]

Originally Posted by Zchas13

I too have been wondering about how to do this.

I've not done it, but was wondering why no-one has suggested waiting til the tank is virtually dry, adding the moly into the diesel tank then and running it til it stops?

Who said it hasn't been suggested ? There are plenty of posts about doing it this way. The OP said he didn't want to do it via dilution method, and there will be some dilution adding 5ltrs to the tank, even it was run as low as you dare.

[Zchas13]

Originally Posted by colinbos

Who said it hasn't been suggested ? There are plenty of posts about doing it this way. The OP said he didn't want to do it via dilution method, and there will be some dilution adding 5ltrs to the tank, even it was run as low as you dare.

OK, what about running til completely dry tank, adding the moly, running to dry again? Any problem with this?

If not, why do people bother interrupting the fuel supply on the 163 version as my suggestion is easier to do?

[cheshired5]

Originally Posted by Zchas13

why do people bother interrupting the fuel supply on the 163 version as my suggestion is easier to do?

1. Interrupting the fuel circuit in the engine bay creates a very small feed and return loop which in turn generates significantly more heat in the Diesel Purge giving a more thorough clean.

2. It keeps the strong detergent effect out of the tank. You don't want to unsettle possible tank sediment and clog the in tank pump and fuel filter.

3. The engine bay loop means you can effectively clean your injectors and HP pump with a tenth of the quantity.

[Zchas13]

Originally Posted by cheshired5

1. Interrupting the fuel circuit in the engine bay creates a very small feed and return loop which in turn generates significantly more heat in the Diesel Purge giving a more thorough clean.

2. It keeps the strong detergent effect out of the tank. You don't want to unsettle possible tank sediment and clog the in tank pump and fuel filter.

3. The engine bay loop means you can effectively clean your injectors and HP pump with a tenth of the quantity.

OK, so looking at the risk v reward of doing what I suggest, what is the risk of sediment in the tank causing mischief to the engine with a fuel filter in place?

When the alternative that is suggested to do so is impossible with the 185 engine compare to what can be done to the 163?

[cheshired5]

Originally Posted by Zchas13

OK, so looking at the risk v reward of doing what I suggest, what is the risk of sediment in the tank causing mischief to the engine with a fuel filter in place?

The risk is variable dependant on several factors so you'll have to do it and let us know.

Originally Posted by Zchas13

When the alternative that is suggested to do so is impossible with the 185 engine

Nothing is impossible and if I had a Euro 4, I'm certain that I'd work out a way.