'98 v70 keeps blowing fuel pump fuse

We have a 1998 V70 with a fuel pump fuse problem. Earlier this year, the car developed a problem where it would occasionally blow out the fuel pump fuse and refuse to start. At first, replacing the fuel pump fuse would fix the problem for a few months, but then the fuel pump fuse started blowing more and more often. (It seems to blow the moment you start the car - so, we replace the fuse, start it up and it runs fine, until you turn it off and have to start it up again! The fuse never blows while the car is running.)

Now the car is almost undriveable, it's so unreliable and goes through so many fuses. Sometimes we use two or three fuses just to get it going. We have taken it to two independent garages. The first could find nothing wrong and suggested we replace the 10 amp fuse with a 20 amp fuse (which we did, but it didn't seem like very good advice).

So we took it to a second garage, which also could find no mechanical problems, but they also checked the codes and said the car comes up with all kinds of weird codes that make no sense. The second garage suggests it's a software problem and that we take it to a Volvo dealer, because perhaps the software is causing the fuse to blow.

Anybody heard of anything like this happening before with a V70?

Reply to
k.lzuhl
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Are you sure it's a 10 amp fuse? In my '98 S70 it's a 20 amp fuse for the fuel pump an ignition combined (very dumb combination).

Anyway, mine had a very similar same problem. The fuse wasn't exactly blowing though, the wire inside that is supposed to break was obviously fine. What was happening was the fuse was getting so hot that the plastic part was melting. This made it change shape, which made the spade contacts not make contact anymore. Pretty strange. I figured the plastic fusebox chassis was weak and making the new fuses' spades not make very good contact in the first place.

A few months ago when I first tried this I was down to blowing that fuse every one or two trips, and sometimes more than one to get the car started. Just like you, once it was running it was fine.

My solution was to take a brand new fuse and slightly bend both spades in opposite directions from each other. It seems to work. The car only failed to start once since then, and taking out the bent (bent by me, not by itself) fuse and putting it right back in worked. Since then no problems. I also bought a new battery over a month ago and the car started much quicker (before the engine would turn over at least a few seconds before catching, now it cranks much faster and catches immediately).

Right at the same time my air conditioning compressor intermittently failed to come on at all. The problem was pretty obvious when I found it worked if I pushed down on the A/C relay. This is in the same box as the problem fuse (the one with about half a dozen relays and half a dozen fuses, next to the one with a few dozen fuses). Bending the spades on that relay did the trick, no problems since then.

What can I say... sometimes I wonder if Volvo, Bosch, and Lucas made a secret pact in 1998.

Reply to
Jim Carriere

1st) You state your car is a 1998 model No software for this car 1999& up use software 2nd) get a third diagnose from another qualified repair shop because the first 2 do not sound to swift 3rd) Has the fuel pump been checked & or replaced & all the connections checked?
Reply to
Glenn Klein

Seems like a simple problem to deal with, and odd that the shop did not just replace the pump straight away. Seems like SOP to just replace suspect parts without even testing at all nowadays.

I also thing that unplugging all related electrical connections that supply current to the fuel pumps and cleaning them is in order. After that, just throw in another pump. OWrst case is that you end up with a spare pump. Even a used one to test the situation would be one way to go.

__ __ Randy & \ \/ /alerie's \__/olvos '90 245 Estate - '93 965 Estate "Shelby" & "Kate"

Reply to
Randy G.

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