whatsit

[clivvy]

guys, on the TDI, whats the thing on the left of the engine, near the intercooler. brass coloured, with a sort of lever you can push upwards, and theres an adjustment screw there as well...what does it do? I noticed my screw looked out of adjustment, and I want to put it right...

 

[rayf3262]

Its probably the air dozer valve... shuts off the air when you stop the engine.
If so, it should snap shut on switch off and the slowly return.

If not it could be the EGR nonsense...

 

[clivvy]

no idea, i dont think its the EGR though as thats at the back. This thing seems to operate a valve of some sort in the I/C "tube", so if I push it up, it opens (or closes cant remember!) but I dont know what it is, or why there is an adjustment screw....

 

[rayf3262]

no idea, i dont think its the EGR though as thats at the back. This thing seems to operate a valve of some sort in the I/C "tube", so if I push it up, it opens (or closes cant remember!) but I dont know what it is, or why there is an adjustment screw....

It stops engine judder/shake when you switch off... by strangling the air supply.
You can always bin it as its pretty useless really. Just another restriction in the air flow...

 

[clivvy]

ohhh, is that what it is! hmm, ill try fidilling with the screw a few times and see what happens.

cheers!

 

[rayf3262]

ohhh, is that what it is! hmm, ill try fidilling with the screw a few times and see what happens.

cheers!

If you are going to leave it in place the best adjustment would be to ensure it is fully open under running conditions.
You dont want it parked at an odd angle disrupting the air flow.

 

[clivvy]

ah ok thanks for the advice, it is currently set to be fully open, although with that in mind why there is an adjustment screw in the first place beats me!?!

 

[badger]

It is the air balance flap or butterfly, it works by limiting the incoming fresh air when the EGR is operating, if you block off the EGR and leave this flap in place it will screw up the air/fuel balance, and make your economy and smoke output worse.
If it is not working correctly and EGR is still in place you will get the similar effect.
I have read many times on this forum that it is some kind of anti judder device, but don’t know where this info came from, the service manual explains the devices operation and it is in the EGR circuit.
Page 431 of the manual explains its operation, reason it closes at engine stop is the vacuum is lost, all the valves return to normal state, it is called a throttle control unit.
If it wasn’t there the EGR wouldn’t work properly, not that it does anyway.
Ditch the EGR and remove the round plate in the device you have pictured, it is attached by two screws and then slides out.

steve

 

[clivvy]

thansk for the info Steve, very informative. I have blanked off one end of the egr pipe nearest the egr itself, thats all I have done, and not noticed any difference really (i dont feel its running that great as it is) so by your suggestion, removing the plate from inside the air balance thingy I might notice a positive change? If so, ill do that this weekend. How do I open this device, does the top just screw off? Is it easily reveresed if something goes wrong (i.e. pop the plate back in) OR do you recommend completely blanking off the egr as well?

 

[badger]

Manual shows different opening times for each valve, egr and throttle at each stage.
Blocked off the EGR, either by stopping vacuum (ball bearing) or making plate, but ECU (computer) will still assume it is present and working, so when it thinks EGR is open and pumping in air all but dirty air, it will close fresh air flap, so your car will be short of one of it main requirements, air to burn the fuel.
Take off intercooler, two machine screws hold the butterfly to shaft, undo them and round plate comes sliding out, ECU thinks both this and EGR are working so no issues with mil light and all air is clean and fresh and cool, why fit an intercooler and then half the time squirt hot air in, on modern engines the egr gas is cooled by yet another radiator/cooling system.
putting back is just as simple if you need to.
I also changed the valve in the outlet banjo of my fuel pump, I am now getting more power and average of 440 to a tank of fuel, prior to the valve/spring I was getting 390, so 10% increase, for a £16 part

steve

 

[clivvy]

thanks Steve, I realise which part you mean to replace, inside the I/C pipe I remove the butterfly flap, ill give that a try and see what happens! It does feel under powered to me, expecially underload such as going up a steep hill...

I have still to check my fuel injectionpump to see if it has a banjo filter or not. I can certainly see some pipe going in at the top but no idea if there is a filter in there or not!

 

[badger]

I am not on about the mini filter, other end of pump has a spring and ball pressure valve which fails or rather deteriorates and reduces internal pump pressure, results in lack of power and hard starting, for the Zexel pump it was £16 and made a big big difference.
Bocsh has same part, don’t know the price.
Best way to get to it is through wheel arch.
I really do drive and love my Maverick, I bought it as near scrap, rebuilt and have done 10,000 miles in 5 months, most of which towing big heavy loads.
Only way I can afford the fuel is someone else is paying at the mo.
I really love it, it is honest if that makes sense, for last 15 years I have had a new car every 3 years, big nice posh, but no soul!
I may buy a newer Terrano one day, but at the mo am happy.

steve

 

[clivvy]

ahhh right I see what you are saying, i might make that one a summer project, but the butterfly egr jobby I can look at this weekend and see if itmakes a difference.

like you, I love my Maverick, despite all the problems I bought it with. I just want to get that little bit more out of it (so need to remove the egr system) and ill be happy!

 

[badger]

your pic of car looks the spitting image of mine, dark blue? p reg?
mine was a Irish car, still on irish plates (northern) odd uk log book entry, no exact date of first use, just a decalred built on or after xxxx, changed to swansea in 2003.my car lacked power on hills and tended to missfire a bit at lowish revs, with new valve all gone, power now very good.
glad i get the chance to drive it so often.

steve

 

[clivvy]

mines that funny sort of mauve/purple colour, wish it was dark blue lol!

I have a few projects in mind but first I want power and better running, so thanks again for the throttle/egr tip and im going to look into this valve thing that you have done, if possible, can you give me more info on it (when you get time)?

I dont have a misfire, the only issues I get is the feeling of a lack of power (not maf or turbo, they are working and it does GO, just not quite as fast as I feel it should) I do however have this very hard to describe idling issue where it seems to almost hunt or rev up of its own accord, and only very slightly (you can see the rev counter needle lift a bit when it does it).

Its certainly a lot better than it was, just not quite perfect! As soon as I have done this, I will start tarting it up. I have a set of Mistral wing mirrors to fit (electronic close), both front arches to repair of the common rust, bumpers to return to black, full service and a good clean. thats about it, other than that, i am very pleased with it and love it to bits, certainly better than my old Fourtrak, and I loved that!

 

[badger]

http://www.nissan4x4ownersclub.com/forum/showthread.php?t=11236&highlight=fault+code

have a look through this thread.

steve

i like the fact that dark blue Ford Maverick, Ford paint code is Nissan Blue!