Fuel Filter Change - Priming / Purging

[silver1011]

Gents,

 

I've searched high and low but no joy.

 

I understand on the CR diesel engines it is necessary to run the fuel pump using VCDS after a fuel filter change, as unlike the PD engines the CR's do not do this via repeated cycling of the ignition.

 

Does anyone have the procedure for doing this using VCDS?

 

Thanks!

[KBPhoto]

I've done both PD & CR engines and not needed to prime the fuel pump / filter with VCDS or any ignition switching or any gimmicks.

It's a straight swap and top up the filter canister with fuel as far as my experiences go.

[wiilydog]

http://www.myturbodiesel.com/wiki/fuel-filter-replacement-2009-vw-jetta-golf-jsw-and-audi-a3-tdi/

[silver1011]

Thanks guys.

 

I changed the fuel filter on the wife's PD140 Octavia a few weeks ago and it was a doddle so am planning to do the same with my CR140 Superb.

 

Just ordered the fuel filter from ECP and will monitor how much fuel is left in the fuel filter housing after the new filter is in.

 

Seems a bit of a chore to buy a container and a fivers worth of diesel just to top up the fuel filter housing.

 

On the Octavia it came up to the top of the filter so the level had only dropped slightly. If I can achieve the same on the Superb I might not need VCDS but it is always good to have it in reserve in case I have any issues.

 

The link above is a great source of advice, the VCDS process is even simpler than I thought!

[KBPhoto]

I topped the fuel filter up with what drained from the old filter. No additional canisters of fuel needed in my experience.

[wiilydog]

If you are not going to top it up with fuel

 

I would prime it using vcds to avoid damage to the high pressure fuel pump as the CR pump relies on fuel to act as lubricant and any air in the system may cause the pump to run dry.

[James@RRG_Skoda_Rochdale]

fill it with new fuel or a fuel treatment.

[ippo88]

Silver how did you get on with this? Was it a straight swap and is it the same for the cr 170?

I'm itching to try changing something else after the air filter i did despite losing a screw!:p

[seboni121]

Do not just change the fuel filter on the cr engine it needs purging ! The hpfp will fail and cost you many dinera , you might get away with it but I have just done mine with vcds and done in 90 seconds , 3 x30s purge you can hear the air leaving the system

[James@RRG_Skoda_Rochdale]

Do not just change the fuel filter on the cr engine it needs purging ! The hpfp will fail and cost you many dinera , you might get away with it but I have just done mine with vcds and done in 90 seconds , 3 x30s purge you can hear the air leaving the system

That's not entirely true. there's still more than adequate lubrication within the pump to crank it over without causing damage. The only reason it doesn't start is the lack of pressure at a the rail.

When it's primed it only primes up to the pump which still turns for a few seconds before starting.

[Miz]

Do not just change the fuel filter on the cr engine it needs purging ! The hpfp will fail and cost you many dinera , you might get away with it but I have just done mine with vcds and done in 90 seconds , 3 x30s purge you can hear the air leaving the system

What is the difference between running the hpfp normally and forcing it to run with vcds? In both instances it is being run dry until the system is purged.

[James@RRG_Skoda_Rochdale]

What is the difference between running the hpfp normally and forcing it to run with vcds? In both instances it is being run dry until the system is purged.

priming the system using diag equipment only operates the lift pump in the tank which supplies fuel up to the hpfp. It will potentially "run dry" wether it's primed or not.

[Miz]

priming the system using diag equipment only operates the lift pump in the tank which supplies fuel up to the hpfp. It will potentially "run dry" wether it's primed or not.

Ta

[seboni121]

What is the difference between running the hpfp normally and forcing it to run with vcds? In both instances it is being run dry until the system is purged.

The new cr engine needs fuel to be lifted to the hpfp as this is required to lubricate , the previous reincarnation diesel did this on turning the ignition key, some say it's fine to just to chuck a new filter and away you go , however the hpfp dries up quickly and therefore not lubricated , sometimes you can get away with it but sometimes you don't , you can get away with it maybe sometimes but if it does fail Jesus it's going to be expensive , if you use the vcds method and prime several times you can hear the air get flushed, when you fill the canister the pipes from the filter to the hpfp are empty , where as using the vcds it fills all pipe work and there is no hesitation on starting or idling , however on the non vcds way it will hesitate and stall and that's the time damage is done , so yes there is two methods and therefore you CHOOSE

[seboni121]

What is the difference between running the hpfp normally and forcing it to run with vcds? In both instances it is being run dry until the system is purged.

No the purging lubrcates the system so not dry

[seboni121]

Ta

So my answer wasn't worth thanking ? Heyho

[Miz]

So my answer wasn't worth thanking ? Heyho

As this is a forum I was being less formal.

 

Thank you so much for enlightening me to the intricacies of the fueling systems on the Skoda Octavia........

 

Better???

[seboni121]

As this is a forum I was being less formal.

 

Thank you so much for enlightening me to the intricacies of the fueling systems on the Skoda Octavia........

 

Better???

Do you know what they say about sarcasm? Hope your hpfp explodes !

[silver1011]

No explosions here!

 

No hesitation, lumpiness or stalling either.

 

In fact it was dead easy....

 

http://www.briskoda.net/forums/topic/346425-oil-and-air-filter-change-skoda-superb-cr140-cffb/

[christopherread1]

Recently changed the fuel filter on my 2011 1.6tdi Octavia. Having read many comments re: VCDS etc. I decided to try the other way! I Removed and changed the filter having pre soaked the new one in fresh diesel, I topped up the filter bowl as much as possible which meant a little was spilt when refitting the top, I then disconnected the fuel return from the HPFP and, holding the pipe as high as possible filled it until it was full, (allowing a little time for air to rise). I then refitted the pipe and started the car, it started immediately and I gently held the revs at about 1500 rpm. for a few minutes. There was no missing at all.

I hope this helps some people confused or frightened by the various theories about this simple job

[keyboardwizard]

The new cr engine needs fuel to be lifted to the hpfp as this is required to lubricate , the previous reincarnation diesel did this on turning the ignition key, some say it's fine to just to chuck a new filter and away you go , however the hpfp dries up quickly and therefore not lubricated , sometimes you can get away with it but sometimes you don't , you can get away with it maybe sometimes but if it does fail Jesus it's going to be expensive , if you use the vcds method and prime several times you can hear the air get flushed, when you fill the canister the pipes from the filter to the hpfp are empty , where as using the vcds it fills all pipe work and there is no hesitation on starting or idling , however on the non vcds way it will hesitate and stall and that's the time damage is done , so yes there is two methods and therefore you CHOOSE

I have a fabia 1.6tdi CR RE 63 and thinking of changing my fuel filter it has 2 pipes on the filter I was going to clamp the pipes remove the filter fill new filter with fuel with a syringe put fuel in the pipes just before refitting. I have no vcds. How much fuel would be left in the pipes to the tank and to the  hpfp?

[sparky2]

I would have thought there was very little in the pipes compared to whats in the fuel filter and if you can refill the filter itself with clean diesel there should be no probs, I changed the filter on a Fabia VRS and I had a problem of it leaking after ! It turned out to be the fuel thermostat which is like a T piece on the top which had broken apart ! Cheers Stuart