When Your 2.1 DJ Fuel Pump Doesn't Prime.. ...

[PaulG]

Hi there!

Having struggled with a sometimes non-starting, poor running, random cutting out van all Summer long, here's a soap-opera to hopefully entertain and inform you! My hope is that it will help others avoid all the hassle I've had!

I managed to get the old girl started last night (the van that is!) I found that the wire between the alternator terminal and the threaded connection post in the black terminal box at the rear LHS of the engine bay (do they call this Terminal 21?) was cracked near the alternator end. This explains why the voltage to Pin 30 on the 2 relays in the relay box (fuel pump, idle speed control unit, injectors etc.) sometimes got battery voltage and sometimes didn't. I've re-made that end and bingo! battery voltage all the time, fuel pump primed, idle speed thingy vibrates, and on cranking the engine started first go! Enough smoke to do justice to a coal fire to start with, but it cleared straight away and ran up to temperature perfectly! First time it's run in 3 weeks of trying things.

Longer story is this. Van started to play up in May 2012. Noticed fuel pump not priming. Checked loads of connections in engine bay, cleaned some, replaced connectors on others. Got it working somehow. Packed up again a few weeks later. Changed fuel pump and filter, seemed to cure it. Packed up again a few weeks later. Tried to figure out permenant live circuit from Haynes book. Got some of it cracked. Van would start sometimes but not others. When it did run it was not the silky smooth thing it used to be. Started to 'stutter' and sometimes cut out altogether, at tickover or at speed - scary! Removed fuel tank and found it had crud in it, replaced it and the filter (again). Seemed OK for a while, then packed up again. Started to suspect ECU so bought second hand one, hence original question. Completely seperately, a fuel pipe split on my car in the drive at home, panicced(!) and called the AA. AA man fixed car and wandered over to look at van sitting forlorn in the garage. He started to trace permenant live circuit while he waited for his next call. Got so far and call came so he had to go. Parting shot was to say that he couldn't see battery votage at the relay pins 30 where we all know battery voltage should be! Spurred on again by this man's help, and two evenings of head-scratiching and I finally figure out the current path from battery to relays. And, as I've said above, wire from alternator to Terminal 21 found to be cracked near alternator, at worst the resistance of this wire measured as 2 Megohms! Wire is well hidden under the rear lip of the engine bay. Longer term I intend to re-make the alternator connections again (not entirely happy with the connector I've used) and replace that entire wire altogether.

So, time will tell again I guess, but this feels like it could be the answer. It would explain all the symptoms if the permenant live was dropping out randomly. I Hope so anyway! This Summer's fun has been spoiled to say the least!

PaulG