My Throttle Bodies fell off the other day, don't ask. So I removed them completely and refitted with new rubber hoses. However, since then I have noticed that the fuel pump runs continuously when I switch the ignition on. Before the pump would run for a few seconds then shut off until I cranked the engine. I did remove the fuel feed and return from the injector rail but have re-fixed them without leaks. Essentially I am running GXSR TBs on to a modified Vauxhall manifold with the original Vauxhall injectors and rail along with a MSnSE. I should say that the car drives perfectly, the only problem is that the fuel is being returned to the tank unnecessarily via the return piping.

Any ideas why?

Did you replace the regulator in the correct place? After the injectors' fuel rail?

had a similar ting on mine,turned out to be a dodgy tranny in the ms unit,worth a look?

As conrod says, usually the fuel pump driver on the ms board. It's Q3 if it's the 2.2 version, not sure about V3. I think some people have uprated it to a TIP120 (you need to check this though...) to make it a bit more 'robust'.

Poo, didn't really want to be taking the whole lot and removing parts etc.

It is a V3 board so an exact location and part type / number would be great as I am definitely not skilled enough to work that out myself.

Thanks for the technical feedback, sorry for being miserable about it.

Steve

If it's stopped working properly since the TBs fell off and were replaced/replumbed, I'd concentrate on finding out whether something's been refitted incorrectly, rather than fret about the EFI system...

...unless a connection shorted out when the TBs fell, of course!

I was probably a little dramatic in my initial statement. The rubber tubes that connect the manifold to the TBs came loose so I removed the TBs, replaced them and refitted the whole lot. They came off as a complete unit and I only had to unclip two electrical connectors to the TPS and air temp sender and the two petrol pipes. I don't think I could have done much damage during that process?
Rescued attachment DSC02130a.JPG

Shouldn't be an electrical problem then!!!

Did you disconnect the tube going to the regulator from the carbs? If so have you put it back on again?

Strange........

Where the two petrol pipes the ones to the fuel rail? Could you have connected each pipe to the wrong tube? IE running the fuel rail backwards therefore stopping the regulator from working?? Then again, that should prevent the engine from running properly... Very strange.....

It's difficult to make any logical connection between what happened to your t//b's, and the problem you're now having with the fuel pump. If yours is the V3 version, it looks less likely (but still possible) to be the fuel pump driver, as this version has better protection for it.

There's a good drawing of the external wiring here:-

ms v3 external wiring

.......which may hopefully assist in your efforts to track the problem down, scroll towards the bottom of the page to find the diagram. Good luck!

Edited to add:-

Probably the easiest way to diagnose it is to remove the large ms connector and turn the ignition back on - if the fuel pump still runs the problem is in the external wiring (or relay), if it stops it's an ms problem.

[Edited on 5/1/09 by GeoffT]

Can't help with your problem Steve but it may be a good idea to fit some bracing between the T/Bs and the manifold. Silicon hoses tend to slip off when used as you have . Found mine had slipped when I got it on a rolling road , they were tied on with a couple of hefty cable ties for a while until I made some metal straps.

Is the fuel pump switched via a relay?

If so, try hitting / replacing it...cold could have got to it...

[Edited on 5/1/09 by stevebubs]

It is operated via a relay, and I like the hit it approach, my kind of mechanics.

Dumb question - could any part of the fuel rail/regulator have got knocked when the TBs fell off the engine?

Steve have you tried reloading your MSQ??