fuel pump prob

[benzburner]

in an attempt to determine whether the fuel pump was dodgy or not, i accidentally short circuited the terminals. the car stopped immediately and refused to re-start. if you leave it for a few minutes it splutters and almost starts then refuses.
does anyone know if maybe i've done real damage or not??

 

[Sprint'n'Go]

I have done similar in my early days. I had a 3ltr vauxhaul senator and hooked up an external 12v supply to the fuel pump to check it out. Unfortunatly I neglected to disconnect the original wires and may have also crossed the polarities. The end result was a fried ECU (AA very nice man came and diagnosed the fault after i reported a home non-start). I was lucky and managed to source the right replacement secondhand for about £100. I dread to think what a modern day merc equivelant would cost!

 

[benzburner]

s***e. that sounds expensive.

 

[television]

in an attempt to determine whether the fuel pump was dodgy or not, i accidentally short circuited the terminals. the car stopped immediately and refused to re-start. if you leave it for a few minutes it splutters and almost starts then refuses.
does anyone know if maybe i've done real damage or not??

Youn normally have a fuel pump relay and fuse, but you do not give any info on what car it is, Put up first 6 figures on VIN

Malcolm

 

[benzburner]

1990 200E. wdb 1240212 b 188619. recently had a new fuel tank. do you think sprint is right about it being the ecu?

 

[C220GJS]

Check the fuse in your OVP relay, it is there to protect the ecu's from voltage surges and may have blown. In the C-class the OVP relay is in the ecu compartment at the nearside rear of the engine compartment , I think it is the same for your car , tall silver relay with a fuse on top .
Geo.

 

[benzburner]

please forgive my ignorance but where will i find the ecu in my car and what should the compartment look like??? thanks everyone

ps is there any other fuses which might have blown in my carelessness?

 

[Richard Moakes]

You are about to reap the benefits of owning an older car

As had already been said, you have either blown the fuse in the OVP relay or blown the fuel pump relay.

Open the bonnet, look in the nearside rear of the engine compartment by the battery, you will see a couple of relays, one of which is silver in colour, but may well be covered by a black cover. On top of that relay (after removing cover), you will see one or two fuses, check to see if they have blown and replace if necessary.

Nearby you will see a rectangular black relay with writing on it such as 4-Zyl or Kickdown etc.... this is the fuel pump relay, and if you have been very unlucky is all that you have blown.

The ECU on these cars doesn't get involved in running the fuel pump, so don't panic, you haven't fried it.

Good Luck,

RIchard

 

[benzburner]

thanks richard.

checked the fuse (10 amp). which was okay. the relay with no fuses had a code 0015459005 on it, is this the one you mean? if so, is there any obvious damage i could look for? i suppose there isn't but better to ask the dumb question.
can i use another from a newer/ older one or bigger engined one?

 

[Richard Moakes]

The relay is specific to the number of cylinders, it acts as a rev limiter to 4000rpm when in neutral.

The relay provides power to the fuel pump(s) when it receiveds a signal that the engine is running or when you are cranking the with the key.

Have you checked the fuses in the main fuse box? Maybe there is a fuel pump fuse in there, it's too cold and wet for me to look outside tonight ;-)

Good Luck,

Richard