Bosch VP30 simple fault diagnosis

[Cap'n ZS]

As fitted to Rover 25 and 45, MG ZR and ZS

As a rule the Bosch VP30 pumps fail in one of 3 ways. Its quite easy to diagnose what the problem is.
First of all the three problems.
1 Timing solanoid failure
2 Metering solanoid failure
3 Pump psg5 ECU failure
lets look at each one in turn.
The image shows the position of the parts on the pump.



1. Timing solanoid failure
IF this happens the engine will still run, but will sound like an old tractor on its last legs. You'll also get a loss of power. Its not advisable to run for prolonged time as the timing is now heavily advanced and puts alot of strain on the engine. This can start intermittently or suddenly happen.
The timing solanoid is under the pump. It can be replaced in situ. Heres a link to a howto by Mad http://forums.mg-rover.org/showthread.php?t=412181. Its held by two torx bolts which are quite hard to get at. Also its sealed against diesel so will be tight to get out. The wiring to it is not on a plug and will have to be cut and spliced. This also applies to the metering solanoid.
Heres a picture of the two solanoids removed from the pump.


2. Metering solanoid failure
IF this happens the engine will stop. This usually happens suddenly without warning. It can be confusing as to what the problem is because if the injector pipe union is cracked open, diesel will still come out. Its just not under enough pressure to cause the injector to open.
To replaced the metering solanoid in situ is fairly easy if you have the tools to do it. This youtube vid shows a metering solanoid removing tool being made. It can be made from 32mm pipe, you dont need to use a socket
http://www.youtube.com/watch?v=uontvecMqI0
You'll need to remove all the injector pipes, and the extensions that they are bolted to. Once the sleeve has been loosened the metering solanoid can be extracted from the pump, but it will be very tight. To refit you'll need to use a "C" spanner, something like this.
www.ebay.co.uk/itm/140811513502
As you tighten the sleeve it draws the metering solanoid into the pump. It will get tight when its fully home. You'll need to use the extracting tool to just finnish off the job as it has to be done up very tight. Carefull positioning of the metering unit is essential as it can spin round and the removal tool won't quite do 1/4 of a turn.
Here's some tools I made and used



3 Pump psg5 ECU failure
This unfortunately will 99% of the time give exactly the same symptoms as a metering solanoid failure. Sometimes, but not always it will put the engine light on.

To successfully differentiate between metering solanoid failure and pump ecu failure there is a simple test you can perform. Cut the two wires from the pump ecu to the metering solanoid. put a multimeter on the two wires from the pump and get somebody to turn on the ignition. You should see 12volts or there abouts, and then dropping to about 6 volts when the engine is turned over.
If no power is registered the ECU has failed. If you do get power then the metering solanoid has failed.
If the pump ecu has failed is usually down to a crack in the circuit board which cannot be repaired. Easiest thing to do is replace the pump in this circumstance as removing the circuit board from the pump is very difficult due to overly tight torx screws that are not very strong.



As you can see I managed to get them out, but dont even try unless you have a quality T10 torx bit. A cheap one will just break off in the top of the screw.



After replacing solanoids
The pump will be totally drained of diesel and despite pumping the priming bulb and bleeding at the injector pipes the engine can be very hard to start afterwards.

[jakeybayliss]

Very help full

[R420SLDI]

Thanks this pretty use full, does anyone happen to know if these solanoids actually have a quoted service life ?


Sent from my iPhone using Tapatalk

[Dakta]

they should last the life of the pump

question is, how long should the pump last


Nice thread, it's about time we nailed this subject down. I don't like chucking good pumps away.

[Bunny_Brain]

This is an accurate summary from my experience.

When my psg5 ECU failed I got a "loss of communications with fuel pump" (to paraphrase my SP ACR 4 reader) message and a "fuel quantity solenoid" error also came up after a period of cranking. I,m not sure how the latter code was derived with the pump ecu dead unless the main ECU knows the lift sensor is not being lifted, in which case slackened pipes should give the same fault. I got no EML, the car just stopped.

I took the pump to CF Parkinsons in Lincoln and they could not extract any fault codes from the psg5 and confirmed my worst fears. They replaced it and with it comes both solenoids for reasons mentioned above; they are not pluggable and there are no splices in my repaired pump.

There are people who claim they can repair the ECU for about 250- 300 quid, its not the route I would take, its not far off that for a new one if you go to a decent non ripoff Bosch agent, and you get both solenoids thrown in.

[mad]

yea good write up, would just mention the fault codes and make it a sticky. Is coming more and more common.

[Rik420SDi]

As above - good work Jim, useful info and a definate <sticky> candidate

[E_T_V]

Sticky it and can I lift it for my rover diesel site (particualy when pics are added)

Pretty please?

[jakeybayliss]

You have a website.. Oo doo tell

[Cap'n ZS]

Originally Posted by mad

yea good write up, would just mention the fault codes and make it a sticky. Is coming more and more common.

If anybody can list these fault codes I'll gladly list them.

Originally Posted by E_T_V

Sticky it and can I lift it for my rover diesel site (particualy when pics are added)

Pretty please?

Yeah no probs Dan. I didn't get chance to get to the workshop today to take pictures, but I'm definitely going to be there tomorrow.

[Bunny_Brain]

Originally Posted by Cap'n ZS

If anybody can list these fault codes I'll gladly list them.


Yeah no probs Dan. I didn't get chance to get to the workshop today to take pictures, but I'm definitely going to be there tomorrow.

Add the connections to the pump as well if you want. Viz

pump pinout is as follows

Pin 1 Yellow to pin 99 on ecm (canbus low)
pin 2 white/grey to pin 100 on ecm (canbus high)
pin 5 red to pin to pin 105 on ecm (labelled fuel shut off so must supply/control the fuel quantity solenoid circuit as there is no shut off solenoid as such)
pin 6 black to earth
pin 7 orange/brown 12 Volt supply from relay 191 in engine management fuse box)
pin 8 green/orange pin 91 on ecm (engine speed output to pump)

[E_T_V]

www.roverdiesel.co.uk

Fault codes are here I think
http://www.roverdiesel.co.uk/electri...ult-codes.html

When the photos appear I'll set you up an account on my site so that you can add stuff in future if you want to.

[Cap'n ZS]

I think I might have one already Dan. I'll check.

[Cap'n ZS]

Updated with pictures

[E_T_V]

Copied accross to my website for posterity.

http://roverdiesel.co.uk/menucommonf...t-finding.html


Cheers

[Bobby_Dazzler]

IF this happens the engine will still run, but will sound like an old tractor on its last legs. You'll also get a loss of power.

Just curious about this...When you say loss of power, are we talking a loss of acceleration? Because I am having issues with a loss of acceleration at higher speeds (around 80-90 mph)

[Cap'n ZS]

I'm talking about serious loss of power. I very much doubt it would make 90 mph, and mores to the point it would make so much noise trying you'd back off....seriously you would!

[MG Nabz]

Would a failed pump make the glow plug light on the dash not work? My car turns over but doesn't start, it is squirting fuel out when I cracked a nut off but not sure if its under hi pressure or not

[E_T_V]

No, as stated in your other thread.

If the glow plug light isn't comming on (and I'm guessing the engine management light isnt either), then chances are the ECU isn't getting power.

If the pump is dead the ECU will still try to switch the plugs on and off at the appropriate time.

[markiboy]

hi guys, what would cause lumpy tick over from time to time and if you restart it its smooth again?

thanks mark