2002 V70 Starting issue, accidentally fixed?

cyberwolf · Post by **cyberwolf** » 31 Dec 2014, 13:37

Our 2002 V70 suddenly wouldn't start this morning. Cranked over fine, but no firing at all. I don't have a pressure gauge but there was no fuel coming out of the check port. The fuel relay sounded fine and there was power at the fuel pump wire, so I started taking things apart for a fuel pump replacement.

I got the drivers side level sensor cover loose and pulled the sensor out a little and then put everything back together finger tight. Moving on to the fuel pump cover I realized that I had not disconnected the battery yet. When I was disconnecting it, I remembered reading something about touching the terminals together to clear codes. I did that and on a whim tried starting the car. It started immediately and now runs fine. One of two things I did fixed it.

Any thoughts on why jostling the level sensor or clearing codes would have immediately rectified this issue?

Post by **precopster** » 31 Dec 2014, 14:16

Next time it occurs try testing the green lead at the fuel pump cover for power upon ignition reaching Pos II. It will be a quick 2 second supply of power.

There is a fuel pump module on plus 2002s so resetting the battery may have got that module going. Perhaps jimmy57 can chime in on this one as I'm not certain of the location.

cyberwolf · Post by **cyberwolf** » 31 Dec 2014, 17:32

I spoke too soon. After a short drive, the car will now start, but almost immediately sputters and dies. It will start again right away, but will not stay running. It acted this way once before and a vacuum line seemed to fix it. Not sure where to look now.

Post by **precopster** » 31 Dec 2014, 19:19

Redo your basic checks again such as pressure at the rail, then go to the green lead at the sender cover as I suggested in my last post to check for power at ignition on. If there is no voltage here the next step is the fuel supply module.

cyberwolf · Post by **cyberwolf** » 31 Dec 2014, 20:37

I don't have a gauge, but there is a lot of pressure at the rail now. Fuel sprays out when the valve core is depressed. I had checked the green wire before, and it had power. The car is in a parking lot now, so further checks are going to have to wait until tomorrow.

Post by **precopster** » 31 Dec 2014, 20:42

Before battery goes totally flat does the cranking speed seem faster than usual?
If it does place a teaspoon of engine oil in the spark plug holes as there may be a lack of compression.

cyberwolf · Post by **cyberwolf** » 01 Jan 2015, 15:20

I did a little more testing for power at the sensor cover with the following results. One of the green wires has no power. There is now no fuel pressure at the rail.

Thanks for your help so far! It is much appreciated.

Post by **precopster** » 01 Jan 2015, 22:54

Sorry no access to wiring diagrams from where I lie (2nd day of back trouble) so just from memory I'm referring to black and green thick wires at the RHS port once the sender has been lifted. These carry power and earth directly to the pump. The other four are red and carry both fuel sender signals.

Post by **precopster** » 02 Jan 2015, 21:16

OK I had a quick look at the connector going to the fuel sender hatch on my 01 XC70 and it's the blue/red carrying power and the black is earth on the smaller connector.

Check that the earth black has continuity to chassis. The blue/red should have power for -1 second if motor is not running. If motor runs it should stay live.

cyberwolf · Post by **cyberwolf** » 03 Jan 2015, 07:06

Excellent. Thank you. I picked up a fuel pump last night and am about to start the replacement right now. This eases my mind that it is most likely the pump.

Hope your back's feeling better.