Removal/Cleaning of ERG Valve to cure limp home mode

[Focusits2006]

Hello has anyone removed, cleaned and or replaced a egr valve on a Ford Focus 2006 1.8 TDCI

[Tdci-Peter]

On 12/6/2017 at 7:18 PM, Focusits2006 said:

Hello has anyone removed, cleaned and or replaced a egr valve on a Ford Focus 2006 1.8 TDCI

I have been having problems with the EGR valve on my car since 2012. Typical symptoms are little hesitations when pulling away, or when gently taking up power after decelerating, or just when driving under light load. If the problem worsens, the MIL (engine warning lamp) will come on, with an error code (DTC) like P0490, P0400 to P0409 or P0486 to P0489.

On the 1.8TDCI, it can be blanked off quite easily, and this will remove the drivability problems, but may not cure the problem of the MIL coming on. Blanking plates can be bought off eBay for a few quid, go for a stainless steel one without hole. Blanking the EGR does not make the MIL come on (but see below), nor will it make the car fail an MoT (Edit: Since about May 2018, visible modifications to an EGR will be a fail if spotted by the tester).

To install the blanking plate, unless you have very slim, flexible arms, you will have to remove the plastic panels under the wipers as below, then just remove the two bolts fastening the bellows type pipe to the EGR valve, ease the pipe back, ensure everything is clean, and dirt has not got in the gap, slide in the plate and re-assemble. I use a little silicone grease (non-setting) as a sealant, but this is not essential. Tiny leaks here will not matter.

If the MIL still comes on, then there is a problem with the actuator. There is a motor and position sensor in the actuator, and if the ECU does not see the actuator move when it expects it to, it will flag up an error. It tests the EGR valve each time the ignition is turned off, there is a distinct rattle and clunk sound. I suspect the error code comes up if this test fails.

So if blanking is not the answer, or you want to investigate further, it is possible to remove the actuator fairly easily. The valve itself is built into the inlet manifold, and I have found no way to remove it, or even to see it. To remove the inlet manifold will need releasing the exhaust from the cat, removing the cat and the turbo, and removing the exhaust manifold first. This is all down the back of the engine, hard to reach, and is likely to have several well rusted in bolts or nuts to deal with. So it is a major job.

The valve seems to be quite a robust and simple design, I think it is a simple poppet valve. If clogged, it is likely that the inlet manifold and cylinder head are in a similar condition, and a full clean out is needed, or a new car! Chemical cleaners may have some limited effect, but only in moderate cases. When the actuator is removed, it is possible to feel if the valve moves smoothly or not.

The actuator, however, is poorly designed for its duty in a very high vibration and high temperature situation. Failures seem quite common. In 2012, replacement actuators were not available at all, I had to repair mine. Since then, they have become quite widely available, with prices dropping to £45 to £60 currently. A new inlet manifold with valve in it is £250 to £350, by comparison.

An eBay link (which may not stay valid indefinitely) is:

http://www.ebay.co.uk/itm/EGR-VALVE-FOR-FORD-TRANSIT-CONNECT-S-MAX-GALAXY-FOCUS-MK2-1-8-TDCI-4M5Q9424BE/231628882077?hash=item35ee28409d:g:DfEAAOSwCU1Y3gyv

Despite the title, this is NOT a complete EGR valve, just the actuator part. They will all be non-OEM, Ford never intended it to be replaced separately!

As the actuator is quite easy to remove & replace, after the first time, it is worth taking it off to investigate the problem before investing in a new actuator. If the valve is really sticky, a new actuator will not help.

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Step 1 is to remove the plastic panels under the wipers. This improves access drastically. Ensure the wipers are parked. Usually there is a dirt line on the screen to help with replacement, if not use some tape on the screen as markers. Remove the rubber grommets on the wipers, and undo the nuts. Hold the spanner or ratchet so that you can pull it toward the wiper arm, avoiding putting stress on the drive mechanism. Then lift the Wiper Blades up, and wiggle and tap the arm near the spindles until they come loose, and lift off. 

The upper panel is clipped on by some rather fierce spiky clips all along the front. After levering them off, I flattened all the spikes on one side, to greatly ease future removal. They are still perfectly secure. The panel then just lifts off. Then there are torx head bolts at each end of the lower panel to undo. The lower panel lifts at the front, rotating right up through about 90 deg., then lifts off. Note how the metal curved clips were engaged over it, to aid replacement.

Then unplug the EGR connector. There is a locking tab that must be released, before it will pull out. The four Torx screws holding the actuator to the manifold must be removed. The top two are quite easy. For the lower front one, first remove the nut and screw holding the metal bracket to the end of the actuator. Then using a couple of extension bars, you can get at the bolt as in the photo below.

Note: The screws may be tight if never undone before. Clean out the screw head recess with a small screwdriver. Use a good bit, that is not worn. Push in hard on the tool end of the ratchet, to avoid possible "cam-out". Apply penetrating oil like WD40 or Plus-Gas, though it will not get into the threads much. If still stuck, tap firmly on the screwhead using a flat ended rod or punch. Then tap the Torx bit firmly into the recess before trying again. Keep trying these steps, rather than excess brute force that will damage the tool bit or bolt head!

To get at the almost invisible lower back screw, it may help to remove the screw holding the bracket that supports the big connector, see below:

If you wish to disconnect the connector, it is held together by an M6 bolt (10mm hex head, I think) in the middle. But I have managed without this. There should just be room to get the tool along the back then:

Once the 4 bolts are out, gently tap and pull at the actuator until it comes free, But be careful not to crack the rather brittle alloy! There are two locating pins, and these will tend to hold it together. It is not a good idea to lever between the mating faces, as these need to be flat to make a seal.

Once free of the pins, the mechanism should disconnect easily, though you may need to twist the actuator just a little. The photo below shows the part of the valve in the manifold. The Croc clip is on one of the locating pins. The actuator has a slotted ring that fits over the silver rod that is nearly vertical in the photo.

 

Edited September 26, 2018 by Tdci-Peter
Add MoT note

[Tdci-Peter]

Inspection & testing of 1.8TDCI EGR:

The valve can now be tested for free operation. Point nose pliers should be able to rotate the metal pin. When the valve is fully closed, there will be some initial resistance, but once free, the pin should rotate quite easily. As it does so, the ball bearings at its ends follow the spiral groove, and drive the valve in & out. There should be no tight spots (apart from the fully closed position if driven hard closed), and both ends of the travel should be well defined, and repeatable. There is about 90 deg. of rotation. Another view of the spiral groove is below:

There was a fair amount of oil around inside this part of my egr. I guess that is normal, as some oil does get into the inlet tract from the crankcase breather, and possibly from normal running clearances in the Turbo.

If the valve feels sticky, you could try applying a cleaner like meths, carb cleaner or other suitable solvent, to the valve shaft, operating it, then removing as much cleaner as possible before oiling with clean engine oil.

The gold coloured part seems to be peened into the manifold, I have tried to free it, but with no success. Also the valve itself may hit its seat before coming out. If anyone has an old manifold, they could try to see if there was a removal method that did not wreck the valve.

So apart from cleaning up the mating faces and any dirt or excess oil, there is little more to be done to the valve.

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The actuator can be tested using a power supply (12v to 15v) and a multimeter. I would not advise using a car battery or car 12v supply, as there is a substantial risk of short circuits between the test probes or clips. A low powered (3A max) battery charger would be fine, or a bunch of AA cells to make 12v might suffice.

I found that mini croc-clips just fitted inside the connector, like these:

https://www.rapidonline.com/rvfm-crocodile-lead-pack-63868

or:

The connections to the EGR are;

First try a mutimeter on ohms between Vref (2) and Vgrd (6). See pic (The top cover had been removed from the actuator here, but this operation is not needed, at least not yet!):

The reading should be about 4.5k to 6.5k, but must be stable when the unit is tapped, or when the quadrant gear at the base is rotated by hand. Be careful the clips make decent contact, or you will mistake test clip problems for real problems.

Then test resistance from Vout (4) to Vgrd (6). This should be in the range about 0.5k to 5k, but must be stable when tapped. This reading should change smoothly as the quadrant gear is rotated, and be stable and repeatable at both ends. Test it for quite a few cycles to be sure.

If these readings jump around, are way outside these limits, or do not repeat, then there is a problem with the feedback pot. I had this problem, several times. I have managed to remove an inner cover to access the pot, and adjust the spring tines that contact it. Repairs were needed as no actuator replacement was available at first, in 2012. But the repairs have proved to be rather short term, and a new actuator is probably a better option. For interest, the feedback pot is shown in the photo here:

Next test the motor. It is worth testing the resistance first. Between pins 1 and 5 there should be a low resistance, under 3 ohms. If the quadrant gear is moved, this reading will jump about due to motor back EMF, but if the gear is held completely still at any point in its travel, the resistance should return to the low value.

A simple 12v charger will suffice to test the motor further. Apply 12v, positive to pin 5, negative to pin 1. Ensure the gear is free to move, and apply the power. With 12v (or more), the gear should rotate rapidly to its end stop. On power off, it should snap shut quite abruptly. If a variable power supply is available, this is better as the valve can then be moved slowly over its range, to check for brush problems. But the resistance test also does this.

There is a return spring under the quadrant gear. If this breaks, the valve may not close. One end can just be seen in this photo:

The slotted ring that locates on the valve operating rod can be seen here also.:

I found that the feeble connection between the top plastic cover, and two pins on the motor (see photo) was not good, and I closed down the gaps in the forked parts to make better contact. Unlike the pot repair, this repair has lasted quite well. The motor pins and forks can be seen here. There is also a circlip which holds the main shaft and quadrant gear in place, that is visible here. Removing this circlip (not easy!) allows the return spring and motor to be removed.

As you may be able to tell, my EGR actuator has had various electrical problems. Mostly in the plastic top cover part, but also some connections inside the motor. It has had 130k miles of high vibration and varying temperature to endure (at the start of the problems, more now!), and it has not stood up to it. There are several design weaknesses in it. So it looks like a replacement actuator is now needed.

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Replacement is basically the reverse of dismantling. A few points worth noting are:

Clean (with fine sandpaper if needed) the locating pins and use a near fitting drill bit (not bigger) in the holes to ensure a smooth fit. Ensure the valve operating rod is aligned in its closed state. Trial fit the actuator to the manifold. Check all the screws go smoothly into their threads, clean and oil if needed. Check the mating faces are clean and smooth. I seem to recall there is a gasket, which may need a little repairing if being re-used. I then apply a little silicone grease (non-setting) to the pins and mating faces prior to final assembly. A total seal is not vital here, it will be internally pressurised with intake air, so tiny leaks will not matter.

Care in re-assembly will aid future removal, especially if it is being re-fitted pending replacement. As I said above, removal is really quite easy after the first time, when all the stuck bolts and pins have been dealt with.

 

 

[July9]

On 12/8/2017 at 6:16 PM, Tdci-Peter said:

 

Thanks for your detailed guide!