4.2 D4d Scv Valve Replacement

[RupertRAV4]

4.2 RAV4 D4-D SCV Valves:

Ok, here goes with the details I know about the SCV valves and their replacement on the 4.2 RAV4 D4-D. Or at least this is how I did it, maybe not the best way but it worked for me! I have yet to look on the official Toyota technical website to see if there are any better instructions in their service manual.

Background:

The symptoms were fairly similar to others who have posted on the forum, ie: loss of power, especially at the top end of the rev range above 3000rpm. Sometimes it would be fairly intermittent and at others the RAV could not get out of its own way!! There was no MIL to start with but that soon changed..... It would come on and off but then it came on and stayed on. The DTC stored was P0627 relating mainly (as it says there could be something else causing the problem) to the SCV valves as below:

I also checked the electrical side of the valves, but mine were both in spec. You can check for continuity between the valves and the engine block and resistance across the valves themselves:

And if required the following shows the wiring between the SCV valves and the Engine ECU:

New valves were purchased from Kingo [aka Parts-King on the Forum] for £194.16 inc. VAT & p&p. Part # is: 04221-27011 and is described as: "Pump Kit, Supply". Ace service from him!

Replacement:

Firstly I undid the two nuts holding the coolant tank in place. Then carefully lifted the tank off the studs (and the locating spigot under the tank) and moved it to the left. I managed to fix the right hand hole onto the left hand stud (if that makes sense!) and could then hold it in place with a nut put on finger tight. Just kept it nicely out the way although you could achieve the same thig using a cable tie I guess. Then I removed the air intake pipe running between the front of the intercooler and the throttle body. This is the main, large diameter black pipe in the photo below (the location of the SCV valves is highlighted by the red circle):

Once this is done you should have something which looks like this:

I also removed the nut holding the wiring loom trunking in place (in the green circle) to gain better access. The red circle is where the SCV valves are.

To identify between the two valves, the front one is redish brown and is SCV 1, and the rearmost one is green and is SCV2. I did one valve at a time to ensure I didn't mix them up and started with the rear most one (closest to the engine block) as this is the most difficult to do because of the limited access. Always better to start with the hard one as when you're bored and tired the second one seems easier!

After undoing the electrical connectors to each valve I then removed the cap/allen head screws holding the valves themselves in place. I needed to use a small screwdriver between the flange and the fuel pump to carefully prise the valve out of it's housing as it was quite tight. Once removed you can push the new one into place. Due to the limited access I could not push the valve fully home so used the fixing screws by tightening each screw a few turns each, alternating between each one, to make sure that it went in square. The other valve was changed in the same way but was a little easier due to the better access.

The following photo shows the new rear (green) valve in place and the old front (red) one removed before fitting the new one:

Once both new valves were in place I wiped up as much of the spilt diesel as I could (not much came out when the valves were removed really), just helps to check for leaks if the area you're checking is already dry. Then I replaced all the components I'd taken off.

Not sure if it helped but I pressed the priming button on top of the fuel filter head until I felt resistance to make sure the fuel system was full.

That's it! The engine started almost immediately and ran fine. On the second ignition cycle the MIL went out and has been out since (keeping my fingers crossed here!).

I guess it will be a good idea to get the fault codes cleared at some point as the original DTC will still be present as a historic code. Always good practice to clear the fault codes once you have fixed the problem.

The following photo shows the old valves. The new ones didn't look any different to be honest, except cleaner!

All in it took about 1hour from start to finish.

Hope this helps someone else! :)

[chatman]

Top marks Rupert..... :D :D :D :D :thumbsup: :thumbsup:

Mods can you add this to our top section with the rest.......

[markys]

Good thing that I saw this thread. My brother needs to replace his SCV valve. He already purchased the toyota auto parts that he needs but doesn't know how to install it. Good thing that this thread gives a detailed proc. However, I can't seem to find the pictures.

[Ravmania]

Thanks for this post. Really helpful. This is a fairly easy task albeit a little fiddly but I would have had no idea how to approach it without this post. (Some of the missing images can still be found on google images at the moment - search for 'rav4 scv valve').

I have the same sort of problem - loss of power on acceleration over 3k rpm in 5th,engine warning light eventually comes on but clears after a rest, over longer journeys this gradually becomes apparant in the lower gears too although not as severe.

I took my SCVs out and cleaned them and replaced them and the car was ace again for a couple of days but has now returned to the same problem.

I say 'cleaned' but the internal working parts of both of them looked pristine, no sign of gunk or anything like it so I am guessing the valve mechanism must be jamming in some way or not opening as fully as it should, what I cannot understand is how taking them out and putting them back in would have made any difference?

Does anybody know how these mechanically operate, do they twist around, from their appearance I thought they would twist around but I couldn't get any play in any direction when I removed mine, I was being fairly gentle so as not to cause any damage, but I

couldn't work out how the valves actually physically open and close or if this mechanical action is something that can be observed or not while out of situ?

[RupertRAV4]

Sorry for the missing photos. I've been back into Photobucket and the photos should be back there. Please give me a shout if you can't see them.

[rambler]

hi folks

my 4.2,d4d has just clocked 85'500 miles..,how likely is it that these 'Scv' valves will 'go' in next few months.....next year?

the engine does give the occassional 'kick',but very rare,thought nothing of it...until now :o

other than that .....,the fuel filter cap 'howling' still (despite been replaced),the engine squeeling when i turn it off,apart from these...its all good

[Parts-King]

SCV Valves can be purchased from Kingo!

PM me for details

Kingo

[Aitch]

We too had the dreaded P0627 MIL Code on our 2005 D4-D Previa @ 43k miles - and glad to say that have successfully resolved with replacement of the SCVs with the aforementioned Pump Kit 04221-27011, £219.77 Delivered - apparently these modded replacement SCVs are suitable for ALL the D4-D blocks (even though the official Toyota part systems apparently say 'non-applicable' for the Previas... :censor: )

Aitch

[Parts-King]

Prices have gone up a little, UK delivered price is £225, we keep them in stock and you would normally get one next day from me

Kingo

[Sensei]

A few weeks ago my car started loosing power for a second or two and as it got worse the check engine light came on. I ordered the ScanGauge II as this would be a nice addition to the car and I could read the error codes. Well that didn't work so yesterday I had to let the dealer read the codes for me. They didn't tell me the codes, but they confirmed it was related to the scv valves. The parts were ordered and arrived this morning. Spent a little less than two hours under the hood today (dealer wanted to charge me two hours as well) and testing this evening was successfull. Alle symptoms of hesitation is gone. Thanks a bunch for the info and pics in this thread! It made diagnosing and fixing the problem very easy! And you weren't kidding about the tight quarters down there!

DMF - replaced

SCV - replaced

Timing belt - replaced (once)

Fuel filter (howling) - needs replacing

What's next? :ffs:

[anchorman]

A few weeks ago my car started loosing power for a second or two and as it got worse the check engine light came on. I ordered the ScanGauge II as this would be a nice addition to the car and I could read the error codes. Well that didn't work so yesterday I had to let the dealer read the codes for me. They didn't tell me the codes, but they confirmed it was related to the scv valves. The parts were ordered and arrived this morning. Spent a little less than two hours under the hood today (dealer wanted to charge me two hours as well) and testing this evening was successfull. Alle symptoms of hesitation is gone. Thanks a bunch for the info and pics in this thread! It made diagnosing and fixing the problem very easy! And you weren't kidding about the tight quarters down there!

DMF - replaced

SCV - replaced

Timing belt - replaced (once)

Fuel filter (howling) - needs replacing

What's next? :ffs:

[macdokes]

A few weeks ago my car started loosing power for a second or two and as it got worse the check engine light came on. I ordered the ScanGauge II as this would be a nice addition to the car and I could read the error codes. Well that didn't work so yesterday I had to let the dealer read the codes for me. They didn't tell me the codes, but they confirmed it was related to the scv valves. The parts were ordered and arrived this morning. Spent a little less than two hours under the hood today (dealer wanted to charge me two hours as well) and testing this evening was successfull. Alle symptoms of hesitation is gone. Thanks a bunch for the info and pics in this thread! It made diagnosing and fixing the problem very easy! And you weren't kidding about the tight quarters down there!

DMF - replaced

SCV - replaced

Timing belt - replaced (once)

Fuel filter (howling) - needs replacing

What's next? :ffs:

LOL

I've replaced the same as you have/had the howling noise

Till today when the car stopped dead

I really hope it ish the fuel filter

[Turps]

Is there any way to test the valve to check it is them before laying out the £225 ?

I have all the symptoms described but am very unlucky when it comes to vehicles! And knowing my luck I will probably replace the valves to find no change :(

cheers

[anchorman]

You can do the electrical checks and it should have stored a code. Other than that it is a bit of a gamble.

[Turps]

thanks anchorman

my error code is p1228 and i have done the checks to rule out the pump so am left with the valves. i hve got the valves out so i suppose i will have to go for it and buy a new pair. fingers crossed!

[Turps]

found this on another site,

P1228 - Injector Circuit Cylinder 3 Intermittent

could it be this and not the scv ??

[ahmad1565]

Hi,

i own a corolla d4d 2.0 2003. aprx a month ago, car started facing problem for cold start but would start in 4-5 attempt and hot start was ok. Now since one week, it won't start at all. When i turn the key, engine runs but no start. glow plugs and fuel flter changed recently. do you think if something might be wrong with scv valves?

Thanks.

[anchorman]

It only needs fuel, air and some compression and it will run in some form or another.

Try pumping the plunger on top of the fuel filter. It should be quite stiff but if not it might be short of fuel. Next jack one front wheel up and with it in 4th gear you should feel the pistons going over the compression stroke (DO NOT have the ignition on or it might start!!!) You can take the air filter out and failing that you have to look at things like valve timing and SCVs but check the simple things first. SCVs usually put a fault light up.

[igormus]

Hi,

i own a corolla d4d 2.0 2003. aprx a month ago, car started facing problem for cold start but would start in 4-5 attempt and hot start was ok. Now since one week, it won't start at all. When i turn the key, engine runs but no start. glow plugs and fuel flter changed recently. do you think if something might be wrong with scv valves?

Thanks.

hi mate

at what T you experience an issue with starting? if less then 5 C -- this might be due to parafine origination inside the fuel filter. in case you experience it at T higher then the possible reasons are:

- glow plugs and their el contacts;

- injection timing;

- poor injection;

- lack of compression;

- SCVs;

- air inside of suction fuel system;

- fault with fuel injection pump.

I presume you must be focused on glow plugs;injectors; bleeding of fuel suction system + do not forget to bleed the pump body using a bolt typed plug on the pump side (do not forget to re-tight it).Cheers/Igor

[ahmad1565]

It only needs fuel, air and some compression and it will run in some form or another.

Try pumping the plunger on top of the fuel filter. It should be quite stiff but if not it might be short of fuel. Next jack one front wheel up and with it in 4th gear you should feel the pistons going over the compression stroke (DO NOT have the ignition on or it might start!!!) You can take the air filter out and failing that you have to look at things like valve timing and SCVs but check the simple things first. SCVs usually put a fault light up.

Hi Achorman,

i was getting fault light quite frequent when i was having trouble during cold start. i will try your recommedation tomorrow. Many thanks.

[ahmad1565]

Hi,

i own a corolla d4d 2.0 2003. aprx a month ago, car started facing problem for cold start but would start in 4-5 attempt and hot start was ok. Now since one week, it won't start at all. When i turn the key, engine runs but no start. glow plugs and fuel flter changed recently. do you think if something might be wrong with scv valves?

Thanks.

hi mate

at what T you experience an issue with starting? if less then 5 C -- this might be due to parafine origination inside the fuel filter. in case you experience it at T higher then the possible reasons are:

- glow plugs and their el contacts;

- injection timing;

- poor injection;

- lack of compression;

- SCVs;

- air inside of suction fuel system;

- fault with fuel injection pump.

I presume you must be focused on glow plugs;injectors; bleeding of fuel suction system + do not forget to bleed the pump body using a bolt typed plug on the pump side (do not forget to re-tight it).Cheers/Igor

Hi Mate,

I am here in Mubikille and av temp is around 20 C in the morning. can you please explain a bit about bleeding fuel sytem to release the air. Where exactly is this bolt on the pump?

Cheers.

[anchorman]

There is no bleed bolt on this system. The HP fuel pump is primed by simply pumping that black plunger on top of the filter until it goes stiff.

[ahmad1565]

There is no bleed bolt on this system. The HP fuel pump is primed by simply pumping that black plunger on top of the filter until it goes stiff.

Hi Guys,

After trying all recommendation there was no success. so i decided to take out SCV valves to have a look. Once SCV valves were out, i tested these by giving 12 V from Battery and there was some vibration. then i fitted these valves back and engine was started at first try. it was unbelievable!

However during this operation i manage to blow ALT fuse( 120 V) and most of components are without power. Hope to get it from Toyota.

I thank you all from your support in this forum.

Imran

[jedi134]

There is no bleed bolt on this system. The HP fuel pump is primed by simply pumping that black plunger on top of the filter until it goes stiff.

Hi Guys,

After trying all recommendation there was no success. so i decided to take out SCV valves to have a look. Once SCV valves were out, i tested these by giving 12 V from Battery and there was some vibration. then i fitted these valves back and engine was started at first try. it was unbelievable!

However during this operation i manage to blow ALT fuse( 120 V) and most of components are without power. Hope to get it from Toyota.

I thank you all from your support in this forum.

Imran

I`ll have to remember this one if im every stuck in the middle of no where..............Stick 12v on the SCV valves..... Are these usually fed with 12v?? Even if not seems to have done the trick, may have freed them up in some way....??

Also must make a note to store a 120Amp spare fuse

[anchorman]

I think you've just nuked them into life. You may end up with new ones but at least you have some reasonable confidence they were stuck.