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Fuel Pump problem again, done some testing need some directions

02-14-2011, 05:07 PM
Hi everyone.

1988 chevy s10
4.3L CPI 92-95 (no idea what year, or Vin letter)

My fuel pump quit on me late friday night just as I was heading away for a military exercise. I had my dad get it toed home as I was already late, so I only have been able to look at it today.

I know the sending unit was either bad or not hooked up during the engine swap that I mentioned in a previous thread. And I had a issue with the pump once before where it needed a few wacks to get it going. For the past 2 months since then I have not had one issue with it. I even drove it twice on Friday and no issues at all. When I went to get a pizza, I got their and on my way out the door she didn't want to start. (cranked over with no prime)

The fuel pump is not turning on in either the on or crank position. I know that because normally I hear it inside the cab. (gota love our gm fp's) Today I went to check the fuse and notice I couldn't find a specific fuel pump fuse. No label for one on my box anywhere, unless I am blind, so what else could it be called? I also notice that my 3A crank fuse is missing, and must have been since I got the truck since its been running fine the entire time. Other then a rough idle issue.

I can check my relay on my friends truck if I need to, but I pulled the connector off at the fuelpump and was getting around 5V DC and 2V AC on my DMM at the on position. Battery is too dead to crank. Are these proper readings or at least good enough signs to tell me which ever fuse and the pump relay are working fine?

I noticed what seems to be a ground wire broken off that runs along the connector too. Its just a green wire that seemed to be tied somewhere along the frame. Should the fuel pump run without this ground? I don't know if the tip just broke up recently or if its been like this for awhile.

Now to bring back my old thread that was never really answered. What fuel pump can I go with? I have no idea what is in my truck now, it looks like they used the orig. 88 fuel pump from the 2.8L thats inside the tank, but it could be the one with the swap. The top serial code wore off and I couldnt see a number last time I checked.

I have a 65L tank give or take, so im assuming thats the 13Gal one that pops up under searches?

I found these on ebay, would this work? I am broke, so the cheapest fix would be the best right now for me. If I can find a cheap sending unit and pump like the second one I'll make the effort and buy it because I would like my gas gauge working too :)

just pump

full unit

13 GAL

20 GAL


02-15-2011, 10:01 PM
anyone? I'm running short on time this is my only week with an extra vehicle and I need to get something order. Any help would be greatly appreciated.

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