VR6Steve 0 Posted March 9, 2004 Report Share Posted March 9, 2004 MorningSome of you may be aware that my 97 VR has a bit of a starting problem that my friend is currently trying to solve.Basically the fuel pump is not getting the signal to prime when they key is turned. Therefore the engine struggles to fire until the pressure has built up.He has had a look at the electrics along with an auto electrician and has confirmed ignition live at the fuel pump relay and is now starting to look at the ECU &| If i get this right, having openned up the ECU !dodge he is looking to trace some lives from the EP (?) ports. (Sorry if i am relaying this badly).Now to the point are there any manuals out there that will tell us what each one does and what readings/values we should be seeing from each?Will a Bently manual cover it ?! Thanks in advance for any help you can offer.Steve Link to post Share on other sites
VR6Steve 0 Posted March 9, 2004 Author Report Share Posted March 9, 2004 P.S. I should add that he has AUTODATA at work, but its not giving him the info he wants. Link to post Share on other sites
marco 0 Posted March 9, 2004 Report Share Posted March 9, 2004 Steve,I have a Bentley manaul, I'll have a look later - got to go out for a meeting now.Not sure that the ECU has any effect on the pump feed before cranking, I would have thought it would be a pure switched circuit from the ignition. When you say your mate has established there is live at the relay do you mean in or out from the relay ?I'll get back later. Link to post Share on other sites
antera309 3 Posted March 9, 2004 Report Share Posted March 9, 2004 There is a relay that controls the fuel pump, check this first (assuming you've already checked all fuses). It is relay number 18 or relay number 12 (depending on model year). The arrangement of relays in the fuse box is as follows:19 20 21 22 23 2413 14 15 16 17 181 2 3 4 5 67 8 9 10 11 12---------FUSES----------Hope this helps. Link to post Share on other sites
antera309 3 Posted March 9, 2004 Report Share Posted March 9, 2004 Note that a knackered relay could still show a + output voltage when engaged, but be incapable of flowing the amps required by the fuel pump. Link to post Share on other sites
marco 0 Posted March 9, 2004 Report Share Posted March 9, 2004 Was just about to say the same thing - try a relay as it looks like the power to the relay comes from the ECM. So if the earths are ok it may be that the relay is not handling the current under load - although it runs when cranking ? Link to post Share on other sites
jcorallo 0 Posted March 9, 2004 Report Share Posted March 9, 2004 Yes - the signal for the fuel pump relay comes from the ECU. It simply closes/completes a circuit - so you can check the continuity and subsequent fuel relay and pump operation, by removing the plug to the ECU, and jumpering the appropriate connections. When you do this, you'll hear the pump operating and fuel will flowing through the rail.From the Bently book - note: as far as I can see, it doesnt make a distintion between OBD1 and OBD2:"Jumper terminals 6 and 55 with the ignition ON - fuel pump runs - relay will click"Jules Link to post Share on other sites
VR6Steve 0 Posted March 9, 2004 Author Report Share Posted March 9, 2004 My relay is currently in Jason's Mk3 16v and working fine!Apparently he MAY (nit confirmed) have found the info he was looking for from another friend of ours who works for BOSCH technical.Head scratching continues. I am now suffering severe VR withdrawal symptoms after a week and a half without her. :-( Link to post Share on other sites
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