[Kevin_Mc]

Hi, I've done a search on here but can only really see opinions for petrol engines. I'm looking to replace the paper filter for a decent cone, which is the best option? Back in the day it was always K&N but there's loads to choose from now.

I'm never going to be putting a full induction kit on the car, will be keeping the airbox although I do have the RS style open top and a Velossatech Big Mouth ordered for when I fit the cone. I may consider swapping the crossover pipe to a silicone one if there's a benefit but not overly fussed on doing that.

So, opinions welcome - what works best for the diesel?

 

[Radiator]

Don’t know what’s best, but I’ve a k+n in the standard air box and have no issues with check engine lights which seem to be common when changing filters on the diesel. And that’s with Pumaspeeds 1r mapping.

 

[Robstowl]

I’ve a K&N air filter with silicone induction hose and RS cover on mine and not once has it gone into limp mode, also running Pumaspeed stage 1R.
Not sure about the Velossatech Big Mouth, I’m sure I’ve read they don’t fit the diesel for some reason? Could be wrong though!

I’ve got an uprated engine mount as well which makes a difference getting the power down, can’t recommend that enough.

 

[Kevin_Mc]

I've just ordered myself a K&N. Will need to check with Dreamscience if the Velossatech Big Mouth I bought will fit but from looking at the website apparently it'll fit STs & ST-Lines so hoping it's the same set up throughout the model range.

 

[teflonbilly]

I'm not sure if anything 'works best' other than the stock intake.

Don't expect any power gains, even remapped the power increase is likely to be unaffected whether it's running a standard airbox or aftermarket system. The way a diesel engine works is very different from a petrol, air is in abundance so changing the intake is unlikely to make any real impact.

I'd try to take one for a test drive with an induction kit fitted before spending money on one, or worst case scenario watch a few youtube videos. I think you may end up disappointed by the noise as it will just release the 'inner tractor' as opposed to sound better (IMO).

 

[Kevin_Mc]

I've watched a few clips online of the noise so I'm not expecting it to sound like a petrol at all.

i've had a tuned Fabia vRS in the past so used to the tractor noise. I'm not expecting much, if anything, of a power increase - I'll be happy if there's a bit more noise from the turbo on full throttle. Thank you all for the replies.

 

[WayneST-2]

My car had the K & N filter in the standard closed end air box when I brought it just over a year ago, never had any issues with limp mode.
Recently fitted the RS Airbox Lid, definitely more induction noise, more of a deep roar noise, not like the sucking noise the open filters make on petrol engines, and to me the car feels a bit more responsive, seems to come on boost a bit quicker.
Wouldn't say it's made any difference to the overall power. Still no limp mode issues. As far as I'm aware, mine isn't mapped.

 

[Kevin_Mc]

I fitted my K&N filter and RS style airbox lid tonight. The sound is brilliant and for the first few minutes of driving the car is spot on. Then it goes into limp mode.

It clears when I turn the ignition off and ba k on again but just repeats the cycle. I disconnected the battery for an hour then after reconnecting I left the car running on idle for fifteen minutes to let the MAF reset itself but the issue just came back at the same point on my test drive. Any other things I can try?

 

[WayneST-2]

I fitted my K&N filter and RS style airbox lid tonight. The sound is brilliant and for the first few minutes of driving the car is spot on. Then it goes into limp mode.

It clears when I turn the ignition off and ba k on again but just repeats the cycle. I disconnected the battery for an hour then after reconnecting I left the car running on idle for fifteen minutes to let the MAF reset itself but the issue just came back at the same point on my test drive. Any other things I can try?

Damn, that sucks !!! These Diesel engines do seem to be quite fussy with any type of Air Filter mods, some seem to be fine, others just go to limp mode.

Are you running the Factory Map on your car ? Is the end of the Air Box open or closed (The circular end, next to the Fuse Box? Does your RS Lid have the rubber horseshoe shape bit that seals it to the insulation mat on the underside of the bonnet ?

For reference, mine has a closed end and has the horseshoe shaped seal which is definitely sealing with the bonnet insulation. As far as I know, mine isn't remapped, no real history on the car when I brought it, so can't say 100%, not sure how else you can determine whether it's mapped, other putting on dyne to compare against standard figures.

Maybe it's something that could be rectified by a custom map, they may be able to set the car up to accept the extra air flow. I guess it's the MAF sensor that's making it go into limp mode, not sure if there's any other way of getting that recalibrated for the extra air flow, other than being factored into a remap.

Any other diesel owners on here with a similar setup ? If so, what's your experiences ?

 

[Kevin_Mc]

@WayneST-2, thanks for the reply. The car is 100% bog standard on the Ford factory map. A remap is on the cards actually but I'm saving pennies to go straight to Stage 2 with an intercooler, exhaust etc. It might need to be sooner than planned.

The air box lid has the horseshoe shaped seal which seems to be meeting up with the bonnet insulation. The round end is open but the k&n filter closes that off same as the standard cone.

It's due a service so will be at Ford soon enough, hopefully thy can recalibrate the MAF sensor until I can get it along to Laird Performance or Devine Autotech.

 

[Kevin_Mc]

So an update of sorts... I drove the 40 mile round trip to work today taking it fairly easy and the car was fine. Came on boost no problem, sat at 70 + 10% + 2mph as always. For the last mile of dual carriageway before home I opened it up and was straight into limp mode after a blast of WOT (or whatever the diesel equivalent is) and as soon as the revs passed 4k it went into limp mode. After tomorrow I don't need the car for two weeks as I'm away on holiday and it's going into Ford for a service so I might ask them to have a look and see if they can recalibrate my MAF. Although, I'm happy to give it a go using FordScan if it'll help any.

 

[WayneST-2]

@Kevin_Mc - Not sure if I'm understanding this right "The round end is open but the k&n filter closes that off same as the standard cone."

Does the end of yours look like this, with the open end:

Or this, with closed end:

If the end is open, then maybe it's pulling in too much air and sending the MAF sensor over it's limit.
I have the closed end setup on my car.

You mentioned in Post #8 that you fitted the K&N filter and RS Lid.
Have you tried them separately, ie the standard filter with the RS Lid, then the K&N filter with the standard lid ?

@Robstowl - What setup do you have on yours, Open or closed end ?

 

[Robstowl]

@WayneST-2 Mines the closed end K&N filter with RS top lid and induction hose.
I’ve tried to attach an image not convinced I’ve done it right 🙄😁

 

[Kevin_Mc]

@WayneST-2, its the same as the second photo - the end of the box has the round cut out but the K&N filter is the type with the closed end so it sits in the gap and closes it, same as the standard paper filter with the plastic end.

I fitted both the filter and the lid at the same time. Ideally, I'd like to keep both fitted and if it means getting a map to trick the MAF sensor then I'll just do it and keep saving for Stage 2. I'm hoping there's an easier fix, I'll have a look later today with Forscan.

 

[Kevin_Mc]

So, an update. I spoke to Connor at Devine Autotech about a stage 1 map to boost power and make the most of having a better air filter and he advised removing the K&N and fitting a foam filter instead. The reason being that the K&N allows tiny droplets of oil onto the MAF sensor. This can't be mapped out and is the reason Limp Mode came on after being full throttle through the gears. Normal driving is fine but as soon as air flows at a higher rate it's game over.

So I fitted a Ram Air filter today instead. When doing so I noticed a thin smear of oil over the airbox lid and onto the battery cover, definately coming from the K&N. The Ram Air makes all the difference - no more Limp Mode and the car's a little more responsive and seems to pick up better from low revs. Probably no power increase but it does drive a bit better and sounds a bit nicer.

Additionally, as I like the look of the Velossatech Big Mouth I fitted one today and can confirm they fit the diesel just the same as they do the petrol ST & RS.

 

[WayneST-2]

So, an update. I spoke to Connor at Devine Autotech about a stage 1 map to boost power and make the most of having a better air filter and he advised removing the K&N and fitting a foam filter instead. The reason being that the K&N allows tiny droplets of oil onto the MAF sensor. This can't be mapped out and is the reason Limp Mode came on after being full throttle through the gears. Normal driving is fine but as soon as air flows at a higher rate it's game over.

So I fitted a Ram Air filter today instead. When doing so I noticed a thin smear of oil over the airbox lid and onto the battery cover, definately coming from the K&N. The Ram Air makes all the difference - no more Limp Mode and the car's a little more responsive and seems to pick up better from low revs. Probably no power increase but it does drive a bit better and sounds a bit nicer.

Additionally, as I like the look of the Velossatech Big Mouth I fitted one today and can confirm they fit the diesel just the same as they do the petrol ST & RS.

Nice one Kevin, glad you've managed to find a solution that works properly on your car. Yes the K&N filter is impregnated with oil, it comes like that new from K&N, and also part of the K&N cleaning kit, you need to spread new red oil onto it again after cleaning, but as reported before, never had any limp mode on my car, so I guess this just shows how fussy these Diesel engines are with the air filters.

The foam Ram Air filter you've got on now, does that go inside the plastic air box, or have you removed the air box altogether and just have the filter hanging off the end of the crossover pipe ?
As for the Big Mouth, did you have to remove the Active Grill Shutters to make room for it ?

 

[Kevin_Mc]

Yeah, the Ram Air filter just sits in the airbox as per the standard paper/cotton filter. Again, it's got the closed end that is visible through the round end of the lid so fits as per the standard part.

I had to cut away some of the front cowling with some tin snips to get a rough idea of where the Big Mouth would fit, then tidied it up with a Dremel so it's actually very neat. I ended up removing the two upper grille shutters on that side but as the area is blocked off by the Big Mouth I don't think it'll make any difference. They came out easily so I've kept them safe in case I ever want to revert back to standard.

 

[Markyh5]

Hi all, newbie here do you have a link to this ram air filter by any chance?

thanks in advance