fuel pump issues

**SuperStock** · 07-16-2008, 07:49 PM

OK so I changed the fuel pump on my 98 formula about 3 months ago. It happened that I really didn't need it because the regulator was the issue. No big deal new pump (Walbro 255 lph knock off from HighFlow Fuel systems) is probably a good thing. So I left the filter on for probably to long but finally changed it last friday. I head into Salt Lake City (about 30 miles from where I live) and about 5 miles from my destination I get a power loss and SES light comes on. I keep driving to where I was going shut the car off and try to restart it... nothing. I shut everything off nd listen for the pump to kick on and nothing. I leave it there and tow it home the next day. It sat in my drive way from sat to today (wed) and I go to cut the access panel so I don't have to drop the tank again and out of pure curiosity I turn the key on and theres the pump. So I clear the codes, go for a ride around the block and pump stops again. I cut the access panel pulled the pump out and checked voltage. I get 12 volts for about 2 seconds then dead. I plug it back in and no pump. Is it the pump or something else. Thank You!

P.S. Also may have maybe 700 miles on it since the new pump went in.

**bigrondownhiller** · 07-17-2008, 01:20 PM

Could be the relay. Switch it with another one and see if there is till a problem.

**0rion** · 07-17-2008, 01:44 PM

I agree. Try swapping out that relay and see what happens. Should be able to just switch it with another relay next to it to test it.

**SuperStock** · 07-17-2008, 04:02 PM

that was the first thing I tried next to checkin the fuse... the pump has a 1 year warranty so I am sending it back. Hope thats the problem

**shadowsnkx** · 08-12-2008, 11:08 AM

how hard is the pump to replace. I have a humming in the rear of my car, loss of power and ses flashes. p0307 cyl 7 misfire code. I thought that it must be the pump because of the humming.

**0rion** · 08-12-2008, 01:01 PM

if it were your pump you'd most likely be getting p0300 misfires which would be random on all cyl. The first step is to check your pressure at the rail and see what you have there....should be ~58psi and hold steady. The humming in the pump is probably the bearings in the pump. Mine hummed for a couple of years and when I swapped fuel pumps it was still going. There's a thread somewhere where people have had good luck with a fuel additive for hushing those bearings up some. I'll try to find the thread and post a link for you. Have you pulled that #7 plug and looked at it and the wire?
At the end of the day it could be your fuel pump but I would diagnose it as such instead of just throwing a pump in there. It's time consuming and pricey to swap a pump. If you do the pump yourself you can get them from harris speed works for a couple hundred bucks. If you pay a shop to do it expect to pay around $1k for an OEM replacement.