Mondeo Mk3 inlet manifold remove / PCV hose replace

Disclaimer: I am a complete amateur at this stuff. Please do your own research and use your own common sense. I'm not responsible for any damage you do to yourself or to your car. I'm just sharing my own experiences here for the hell of it :)

So, aide-memoire in case I have to do this again...

Engine idle had been quite high and erratic on our 2004 Mondeo for several months. Not too bothered until garage pointed out that it was due to air leak in the PCV (positive crankcase ventilation) system, specifically a split in a rubber hose, and that it would cost mega £££’s to get it fixed.

The PCV hose (aka oil separator pipe) takes combustion blow-by gases from the crankcase, via a one-way valve, into the inlet manifold. The symptoms of a split PCV hose are high idle (in our case 1000 to 1500 RPM, with short surges to 2000 RPM when vehicle came to a stop) and poor fuel consumption. You’re also getting unfiltered air into the engine through the split; this doesn’t get much of a mention but probably isn’t a good thing.

There’s a bit of history with the Mazda L/Ford Duratec HE engine used in Mondeo Mk3 in relation to this. Covered in more detail here but it goes something like this:

• 2000-late 2002 (Pre-‘facelift’ cars). Inlet manifold with small diameter PCV hose. Also features “swirl flaps of death”; air flow tumblers which after time work loose, disintegrate and are ingested into the cylinders usually writing off the engine. Owners of these cars have usually removed the swirl flaps as they are not really necessary.

• Late 2002 onwards (some pre-facelift but mostly facelift cars i.e after mid-2003). Manifold was revised mainly to fix swirl flap weakness, but also introduced a wider PCV hose which unfortunately, years later, has become prone to splitting... causing vacuum leak and idle problems.

• Ford then released a revised PCV hose which is not prone to splitting ( part number is 1440473). Not sure but this may have been fitted as standard to cars made after 2004/2005 (?). In any case if you’ve got the original hose in a 2004/5 Mondeo then if it hasn’t already split it soon will and you will need to replace with the newer hose.

The replacement PCV hose costs £40 inc VAT which is pretty steep for a 6” long piece of rubber tube, but that’s not the worst of it... Mazda decided to locate the PCV valve and hose deep down behind the inlet manifold and it’s impossible to replace these items without first taking the manifold off, which is why it’s an expensive garage job (4 or 5 hours labour).

Somebody on TalkFord forum actually managed to replace their hose by removing the throttle body and flap actuator only and leaving the manifold in place, so I tried that first but found it impossible… he/she must have very small hands!

So I carried on with manifold removal as per this “Craig’s DIY Car” video (No need for any Haynes manual – his video covers everything perfectly)

Engine with throttle body removed (placcy bag over it to stop things falling in), flap actuator removed, and the electrical & fuel injector connectors labelled and removed. Note: Don’t use white paper stickers next time... they fall off. Use white insulating tape instead.

I could not manage to disconnect the TMAP sensor down at the front, so unscrewed and pulled the whole unit out instead.

However there are three or four others connectors down below, at the front, which were really hard to reach and wired in tightly so I was afraid I’d break some wiring down there. Gave up on those in fact. Two on the left... one for starter motor (?) and one which looked a bit homemade/repaired with insulating tape and one or two on the right. Need to properly id these at some point...

Lost my nerve at this stage, and time was running out for me too, so decided to change only the PCV hose with a partial manifold removal… i.e. if you cannot get the manifold completely out then you will not be able to replace the PCV valve and I also found I could not change the manifold gaskets either like this (but you can generally re-use the existing ones – they are rubber. Just be careful with them).

So… carried on with removing the manifold bolts. As I was unlikely to be able to fully remove the manifold with some wiring still in place, had to be really careful not to drop any bolts. Small but strong magnet (e.g from a fridge magnet) blutacked into the 10mm socket did the job. Make sure not to let the magnet touch the side of the socket itself...socket then attaches itself to other things nearby as it approaches the bolt head and, if not secured well enough, it gets left behind when you try and remove it. So yes, also wrap the socket, adaptors, extensions etc really firmly in insulating tape. Don’t want any of those coming apart.

Socket with the magnet in it…

Socket/extension arrangements that worked for me are shown below...

• The top arrangement worked for most bolts (10mm socket, long ¼” extension, ¼” to 3/8” adaptor, plus a 3/8” to ½” adaptor as required)

• The middle arrangement shown was for removing the TMAP sensor screw (Torx T20 in ¼” socket with ¼” to 3/8” adaptor)
  
• The top rightmost bolt near the throttle body/accelerator cable gubbins needed the universal joint with the long ¼” extension

All bolts are visible except for the middle lower bolt. Tried a torch and mirror for that one but found it easier just to ‘feel’ the socket onto the bolt.

Upper left bolt is almost invisible but you can actually see just a sliver of it through the gaps in the manifold above so use that to ‘see’ the socket onto it.

All bolts (18Nm torque) should crack open without excessive force (i.e very firm hand pressure plus a bit more)

As with the throttle body, flap actuator and dipstick, keep all the bolts and screws safe. Here’s the card that was made up for the manifold bolts… numbering gives the order in which to torque them up again later (i.e from the middle outwards)

This is as far as I got the manifold detached from the engine body with the cabling still in place. Just an inch gap really. Edges of the swirl flaps are visible in each port... they seemed to be in good condition; no freeplay or damage. Does look black and oily in there... normal for a high mileage engine? worn piston rings? PCV valve failing/failed? Don’t seem to be burning any oil though.

Just enough space now to get the PCV hose off… vulcanized/stuck onto each end though. Managed to split the PCV valve end of the hose with a craft knife and was then able to prize it off. Did something similar, and also used some heat, to get the manifold end of the hose off.

Il Bastardo !!! ( 3 inch long split smirking at me )

Here’s the new hose (1440473)

Compared to the old hose we see that the new one has a double wall

You could say it’s rather over-engineered now what with those clips and all. They are glued on but mine fell off whilst trying to fit the pipe. It’s okay though, space is so tight that this tube ain’t moving anywhere and I had no space to manoeuvre the clips back on anyway. With the restricted space I think jubilee clips might be better anyway for any future removal/refitting.

PCV valve end of the new pipe went on first. Heated it up a little first. Still very tight to go on (silicon grease might have helped perhaps?). As with the removal, careful not to use too much sudden force... the PCV valve is plastic and looks quite breakable.

Then the manifold end of the pipe went on... not much space to apply heat to it but managed a little. Somehow managed to get some force onto it through my palm and slowly got it about 90% on… good enough! Hand and arm now badly scratched up and bruised :(

Refitting the bolts, I used the magnetized socket but also tied some thin cotton around each bolt head with the other end tied around my finger. No chance of losing any bolts!

The torque wrench I have is rather large and unwieldy so I was only able to accurately torque up bolts 1, 2, 3, 4, and 7… had to use a smaller wrench and guesstimate 5, 6 and 8. Tighten them up in sequence from the middle outwards.

Next, reconnect all electrical & injector connectors, reattach the TMAP sensor, throttle body, flap actuator, throttle & cruise cables, air inlet pipe and battery. Lastly, don’t forget to reinstall the oil dipstick (this dipstick nearly did!)

Engine started up after three attempts. What a relief !

Warm engine idle is now back down to about 750 rpm. Fuel consumption has reduced from about 30mpg to 38mpg. Nice !

Summary... took me two days to take apart and one day to replace the hose and put all back together again  (i.e read about it, worry about it, check it, double check it, do it, triple check it... for every step). Next time should be much, much quicker. May need to cut that wire that looks ‘home made’... mark each end and then do some terminal block/connector on reassembly etc. Also, apparently I could have lifted the radiator fan out of the way for some better access to those front wires (?)

Concensus on TalkFord forum is to remove swirl flaps even on cars with the revised manifold and flaps. To quote one poster there: ”If it’s not on the menu it can’t get eaten!”
Usually can hear them clattering away when they are going bad. So if that ever happens or if start to get failed PCV valve symptoms then do this job again... but properly and change the PCV valve and remove the flaps. New gaskets too...

• PCV Valve part number is 1331598 ( * )

• Inlet port gasket ( x4 ) part number is 1119284 (but you already have these)

• EGR valve gasket part number is 1119833

• Video for PCV valve replacement

Happy Mondy now... finally getting some TLC :)

( * ) Note to anyone that has strayed here needing to do this job on their car, the part numbers referenced here are for my car. Yours may be different. Would recommend a chat to someone at www.fordpartsuk.com... give them your VIN number and they'll look up the correct part numbers for your car. ( I think you can do this here too: https://www.etis.ford.com/ )