Fuel Pump Relay

[iaint]

Last night while driving home my engine management warnign light came on. The car was driving normally and the advice in the handbook was that it was OK to drive but I should get it to a garage soon.

This morning I have been to have it checked and the fault was the fuel pump relay had shorted to ground.

The garage checked the relay and it was operating normally, they reset the light and now everything is fine.

My question is, should this be something I should be concerned about. Do I now assume that the relay may be on it's way out and if it fails it will leave me stranded and is it worth changing it as a preventative measure.

Or do I do as the garage advised and to assume all is well, that it was a momentary hiccup which may never occur again and if it does, deal with it then.

Any thoughts and opinions would be greatly appreciated.

Thank you
Iain

[JohnFol]

I'm no guru on the subject, but for the sake of £3/4 I'd change it or keep a spare in the glovebox.

[Keith]

If the information the garage gave you was from Testbook then that could have happened at any time and a short to ground in Testbook speak does not necessarily mean a real Short

If it was the fuel pump relay failing you would have quickly come to a halt my guess something else caused the problem

Can you add car and engine details to your post please

[iaint]

Keith

Sorry for the delay in responding, I've not been around this weekend.

The info you asked for is:

MG ZT, 1.8T on a 53 plate. Current mileage is 64K if that's relevent.

It wasn't testbook that the garage used though, I went to an independent garage which I have used before and they use a general diagnostic tool called something like Solus or Solaris, I can't remember the exact name.

I watched as the chap set it up and it read my vin number and knew all the details about my car, make model, engine type, year of manufacture etc.

Thank you for any help you can give.
Iain

[Keith]

Apart from the normal advice of checking your drains are clear to ensure the engine ECU is not swimming I would go by what the garage said, sometimes these things happen

I had my father in laws X type here a couple of weeks ago that did exectly the same thing one morning but has been ok ever since

I would be interested if you go back to know exactly what diag kit they are using though

[iaint]

The diagnostic tool the garage used was the Solus

http://cgi.ebay.co.uk/Snap-On-Solus-Diagnostic-Equipment_W0QQitemZ330051950514QQcategoryZ30921QQr dZ1QQssPageNameZWINQ3aPOST0Q3aRECOQ3aBIDQQcmdZView Item

This is all I could find on it with a google search but it'll give you the idea.

The chap at the garage seemed to think it works with most cars with the exception of some Japanese manufacturers. Apart from that I know nothing else about it.

Thanks for your advice though, the drains have been checked already due to the number of reports of problems both here and on .org.

Fingers crossed that I'll see no more problems but if it returns I'll no doubt be back.

Thanks
Iain

[Keith]

Another bit of kit to investigate :)
Bit expensive though so not one I will be bidding on :)

[iaint]

Hmmmm

My light came back on on Friday but before I could get it plugged in to identify the fault it went out again.

So I now have three questions:
1. I thought when a fault was logged, the light would stay on until a garage reset it. Is this correct and should my light still be on?
2. If it's now gone out, will there still be a record of the fault for the garage to read?
3. Assuming it's the same fault as last time (Fuel relay shorting to ground), does anyone know what the fault may be. Keith has already pointed out that if the relay had failed I would have come to a halt very quickly and something else may have caused the warning light.

Any help would be appreciated.
Iain

[Keith]

Hi Iain
yes if the MIL came on then a fault code should have been logged and recorded. Hopefully last time they cleared the ECU fault memory so this will then be a real message.

As for what the problem is it really depends on what has been logged

If it is still reported as shorting to ground then a chat with an experienced MGR technician is probably the easiest way to pinpoint what that means.

[iaint]

Thanks Keith, I'll get it in and have it checked out. That will probably be the quickest way to get this sorted out.

Iain

[iaint]

Sorry to bring this one up again but I'm still a way off getting it sorted out.

I took the car for a service and MOT and had the computer error log checked. All it says is "undisclosed fault". UNDISCLOSED FAULT, what does that mean ???

I was told by the garage that it is often caused by a minor intermittent electrical fault which can be very difficult to diagnose. They reset the light again but it came on after about 4 hours of driving.

This is now the 3rd time I've had this light and each time the car is running excellently with no drop in performance. Each time I get it checked I have no genuine fault to speak of and each time I get it reset it comes back again within a days

I was looking to change the car in the new year anyway but I don't want to be selling a car with an engine management warning light permenantly on. However I also don't want to be spending big money on getting to the bottom of this.

Does anyone have any thoughts or suggestions which may be of use.

Thank you
Iain