Vacuum system

[CCCars]

Been doing a bit of work on my brakes with a little success, in the course of my investigations I have been looking at the vacuum system as initially a PO had pulled off the vacuum hose at the T piece between the vacuum pump and the servo (TD Auto EPIC fuel pump) so servo assistance was compromised to say the least!
In my research I've been sidetracked into performance, or lack of! EGR waste gates etc. at the moment my vacuum hose is still disconnected as before but blanked so at least my servo is now functioning but what I'd like to know is what are the components which are now not getting any vacuum and what are the effects of this? I have identified the EGR valve and what appears to be a cold start device? then there are some solenoids? in a block at the upper edge of the engine compartment which I can't figure out, the other issue is if I connect my vacuum pump to the disconnected hose I am unable to draw a vacuum no matter how hard I pump so the system is drawing in air somewhere, I've tested the EGR and the cold start flap actuator and they are sound, no leak at the diaphragms and the levers move as they should which leads me back to the unit at the top edge of the engine bay, just below the windscreen, I have had a good look around the transmission but can see no vacuum connection there so assume it is controlled from the ECU?
Another thing I need to clear up is my check engine light remains lit for 5 seconds after starting the engine which I understand is to show there are fault codes present? If the diagnostic socket is in the fusebox under the dash behind the spare fuses it doesn't match the plug on my code reader!
Sorry it's a bit long!
Graham

[MinorMatt]

Im not sure what you mean by a cold start device?

The vaccum only really operates the EGR. Just blank/clamp the pipe at the tee and see if the brakes improve.

Diagnostics plug is just the standard 16 pin OBD type plug - but the van isn't compliant to modern standards

[CCCars]

Hi Matt, on top of my engine there are 2 devices operated by vacuum, the EGR and another which appears to operate a flap in the inlet that I took is to mix warm air into the inlet when the engine is cold but as I can't find any information about the vacuum system I may be wrong, it wouldn't be the first time!
Mine is not the "banana engine" at least it doesn't have a bunch of bananas on top like my mates truck, 2.5 turbo diesel EPIC injection pump auto trans so from what I've read I'm stuck with that so no way to soup it up!
I'll have another look at the diagnostic socket (in the fuse box?) and see if it matches my machine.
A diagram with explanations of the vacuum system would be very helpful as I'm trying to track down the air leak which is destroying the vacuum, at the moment my vacuum is only connected to the servo to make it operate but if I try to draw a vacuum on the rest of the system with my hand held pump and gauge it just leaks away immediately.
Thanks
Graham

[MinorMatt]

Take some photos Graham, there are several variations of engines and parts fitted

If the EGR doens't work its not a problem really

[CCCars]

Hi Matt, progress so far, I removed the components that the vacuum goes to and I think the solenoid valve may be faulty, I unplugged the electrical connection and with ignition on there is 12v to the plug, there are 3 pipe connections on this valve, one from the vacuum pump, one to the EGR valve and the flap valve in inlet and a third one which goes to the air filter housing.
The other component in the mounting I think is a MAP sensor measuring the pressure in the inlet manifold, this has a 3 wire connection plug.
I measured the resistance at the solenoid and got about 30 ohms but when I put 12v on it there was no evidence of anything happening, no click and no change to the passage of air through the valve.
I tried to connect to the diagnostic port, my plug fitted but the scanner couldn't communicate so still no further forward with that one.

[CCCars]

Forgot to mention I noticed a fair bit of oil leaking from the turbo air outlet so suspect the seals are on their way out and the waste gate appears to be seized as I can't move it one way or the other so looks like I may be in the market for a new turbo fairly soon
Also a slight fuel leak at the back of the injection pump, seems to be from one of the injector pipes but they were all tight, may be from somewhere else as there's not much room to get a proper view of the area.
Graham

[CCCars]

Just been doing a bit more research and found reference to the air inlet valve, so which position should it be in, lifted by vacuum or in the down position? I can pipe vacuum to it permanently with a bit of hose if that is best?
Graham

[MinorMatt]

Ok, so the 3 pin one is the MAP (boost) sensor - that won't be connected to the vacuum system at all. The pipe from that should go to the nipple on the front of the manifold.

The solenoid is what controls the EGR. I would leave it, and the EGR electrically connected at the moment and blank the vaccum pipe where it tee's off the pipe between the vacuum pump (on the alternator) and the servo). The EGR vac pipes can be left open to atmosphere.

See what happens with the brakes and see if they improve.

From memory, the vaccum comes from that tee, goes to the solenoid, leaves the solenoid, tee's off one goes to the butterfly and one goes to the EGR itself.

Matt

[CCCars]

OK that's how I left it last time, so just to confirm in it's normal run position there is no vacuum to the EGR and the air inlet flap? At the moment if I apply vacuum to the pipe from the solenoid valve both the EGR and the air inlet valve move but what does the electrical connection on the EGR valve do? is it a switch that detects when it is open? Can't see room for a coil in there so guess it is?
Wish I had a diagram to figure out how this system is supposed to work!
Thanks
Graham

[MinorMatt]

The vacuum is connected to the solenoid - one side has permanent vacuum. The solenoid (via ECU) controls how much vac the EGR assembly will see. If the EGR has no vacuum it should be in the closed (safe) position. You can cable tie the flap in the open position if you want.

The electrical connection on the valve itself is to feedback its position to the ECU. If the ECU requests the EGR opens (i.e. vacuum to the EGR) and the sensor doesn't feedback the appropriate opening it will register a (minor) fault in the vehicle memory. This will have no effect on how the engine runs, but will illuminate the engine management light for 5 seconds when starting.

[MinorMatt]

Something a bit like this

[CCCars]

Hi Matt, don't know what you attached but I got this message You do not have the required permissions to view the files attached to this post.

[CCCars]

OK Matt, got it now, yes that was what I worked out after finding the electrical diagram buried in my Haynes book, I assume the connection to the airbox is to vent the vacuum when the solenoid closes in allowing the flaps to return to the rest position, looks like my solenoid valve is goosed as it is permanently open between the vacuum inlet and the vent destroying the vacuum in the process, so for now I'll leave things as they are.
Have to look at the turbo situation next, I've always felt oil leaking from the turbo is bad!
Graham

[CCCars]

Just wondering if there's an alternative to the Lucas 2000 scanner, I read somewhere it uses an ISO system rather than the more common EOBD OBD2 systems?
Graham

[MinorMatt]

Just wondering if there's an alternative to the Lucas 2000 scanner, I read somewhere it uses an ISO system rather than the more common EOBD OBD2 systems?
Graham

Forscan with a modified ELM327

Or Fords own FDS2000 system