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Technical fuel relay

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Technical fuel relay

noooooo,

dried it and still no luck. still not sending power to the rear pump.

do you think my ecu is knackered as the left plug was really wet rusty and greasy, looks like it has been festering for years and just built up to this.

i am sure it has been tampered with as though its done this before and they have bodged it somehow and sold it on.

I had arranged for a mobile auto electrician to come and look tomorrow, do you still think its worth it as its got to be the rusty etc plug hasnt it??
 
actually does the ecu have a fuse? due to all the water this could have shorted and blown
 
Hi mate,

Just been looking back through this thread.

You have bridged the hight current side of R10 and you get power to the pump.
When you tested the low current side of R10 you say you have 12v. That would indicate the relay is faulty, as the low current side should be switching the high current side. (Effectively bridging the HC side as you have done manually) HOWEVER due to the fact that you have swapped relays etc i would suggest the problem there is more likely due to me not explaining the procedure for testing the low current side well enough, than simply the relay being faulty. It would suggest that you don't actually have 12v on the low side possibly.

Technically the fuel pump and relay should energise without permission from the ECU. As it is switched from the ignition via R9 and then seperately via R10.

So you may well have two seperate issues. You may well find that even when you get the pump running the engine still won't start.

Regarding the ECU connector, that certainly is an issue. If its not causing you issues now it certainly will at some point! As you say it's also possible the water has ingressed into the ECU and caused damage. Also if the pins are tarnished /rusty they won't be making a good enough contact.

I'm sure your auto-electrician will be able to get to the bottom of it, or at least point in the right direction. If you could post back your results here, good or bad, that would be great!

Hopefully all that makes sense! I have my fingers crossed for you (y)

Alan
 
thanks again al and ziggy,

the auto electrician spent over an hour on it and after various tests says the ecu has had it.

he has removed the ecu and given me an address in matlock that can often repair them so hope to try and get this done. ill keep the post updated.

he too thinks the car has previously been bodged up :(
 
Thats a shame, must admit it was starting to look that way. Water ingress on the ECU connectors is a fairly common problem, and that in turn can short various parts of the ECU internally.

Thanks for keeping the thread updated! Fingers crossed they can sort the ECU for you.

Alan
 
just through interest if they cant repair the ECu is the car likely to be scrap?

no idea how much an ecu is, then doesnt it have to be programmed to car by fiat, and then that could not be the only issue anyway :(
 
If the ecu is FUBAR' iwouidnt scrap the car,
Just buy a ecu and bsi from a donor car.
You wouid need the chip from the ignition keys swapping over too. Not a big job to do


There was a company on eBay doing ecus 'they where claiming that they where plug and play-virginised ecus.
 
Hi mate,

As oldhammer says there are ways around it without spending big money.

I do believe that you MAY have a secondary problem though with regards to the fuel pump not priming. However if the auto-electrician has deemed the ECU to be faulty, then best bet is to get that fixed first and then IF the pump still doesnt prime, you can supply the pump manually to test the ECU/ engine and then work on getting the pump going correctly from there, as there are still a few places left to check.

Alan
 
back to the drawing board.

ecutesting want £300 to test and fix my ecu and then they still wont guarantee that it will work ok.

i am not throwing that money at it given they wont guarantee anything so unless i can get one on a breaker i think its game over.

could i ask what the bsi is that i need please?
 
Zipster09 said:
unfortunately not on mine
Click to expand...
You can find which relay is connected to the fuel pump as follows. Firstly remove all the relays. You can then see that one connection of each large relay contact on the fuse box always has battery positive. The relay then switches battery positve to the device being turned on by connecting to the other large contact. So if you put battery positive on the fuel pump purple wire you can see which relay connection now has battery positive on these 'other' large contacts. If you cannot find that contact then you have something broken between the connection and the fuel pump. The fuel pump earth goes via the inertia switch just above the carpet on the right hand side just under the dashboard
 
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