skibbe_96z

I just installed a new Walbro 255 lhp fuel pump because my old pump was going out. I installed the pump in the factory bucket with jb weld on the lid and the factory rubber ring at the base. I spliced the wiring for the new plug with the old plug, soldered it, and heat shrank it. I put it all back together, turned the key, the pump primed and it fired right up, idled rough, then died. It did this over and over again. It finally started to stay alive idling rough around 500rpm but anytime I hit the throttle, it died. I was finally able to get it started while on the throttle and it would rev up to 2500-3000 and fluctuate there until I got off the throttle and it would either die or idle at 500 until I hit the throttle and then die. The wiring for the new fuel pump is a thicker gauge than the existing but splicing it instead of connecting it at the terminals like the other plug wouldn't be causing the issue, would it? Any other suggestions?

Kevin Blown 95 TA

One thing that often goes wrong after a pump swap is the hose comes off the pump. One guy even found a small hole in his replacement hose causing all the trouble. So I would start by checking the fuel pressure.

skibbe_96z

Thank you for your response. I took it apart again tonight to find out I didnt have one of the clamps tight enough on the main fuel line. I put it back together and runs like a champ. Thanks again.

skibbe_96z

Well, I thought it was fixed. It ran for 20 minutes yesterday great. I let it set all day today and went to start it this evening and it was hard to start and idled rough at 500 rpm and died. I took the fuel pump back out and all the fuel line connections were good. The only thing I noticed was the heat shrink had become loose. The soldered connection still looking good but could fuel hitting the bare wire cause it to short out in any way? Has anyone else had a problem with splicing the wires? What has been done to keep fuel from hitting the wire? I am out of ideas. Any help would be greatly appreciated. Thanks.

Injuneer

Where di you buy the Walbro? There are reports of a large number of Chinese counterfeit Walbro pumps on the market.

skibbe_96z

High Flow Performance at Walbro 255 Fuel Pump : Walbro 255LPH : Performance Fuel Pumps : Cheap Fuel Pump : Discount Fuel Pump : Ford : Chevy : Chevrolet : Range Rover : Dodge Ram

Injuneer

Still sounds like you need to check the pressure.

Mystery Bird

That link is not a real Walbro but a knock off. I bought one similar to that which lasted exactly 20 minutes before the car started to run wierd then slowly died.

Lt1son

the walbro i bought and others ive seen that are "real" have the walbro name and part number engraved in the side w/ a made in usa... not sure if yours has that.

Injuneer

If you work your way through the link, it does end up at a (supposedly) made in the USA Walbro:

Walbro F20000169 255LPH Fuel Pump Chevrolet Camaro 1985 - 1997

Not to say it really is a Walbro. I suspect the Chinese just might have figured out how to engrave the Walbro name and part #, and the words "Made in USA" directly into the pump casing. They are masters at copying and counterfeiting anything.

Mystery Bird

Ahh, that's a different link. I used the one from earlier and just scrolled to bottom to see the knock of one and assumed. You know what happens when you assume?

skibbe_96z

I didnt have time to work on it yesterday but I will work on it this evening. I plan on redoing all of the connections, reinstalling it, and changing out the fuel filter and see if it runs well. If it doesnt run well, I will check the fuel pressure to see if the pump is bad. I will keep everyone posted. Thanks for the input.

skibbe_96z

Ok. Finally had time to work on the Camaro again. I checked all the connections, redid the electrical connections just to be safe with a water tight crimp splice and heat shrink, and put in a new fuel filter. It had a hard time getting started. I finally was able to get it to stay alive idling really rough at about 500rpm and checked the fuel pressure. The gauge was showing less than 15 psi. There is no fuel in the vacuum line at the regulator so I am assuming the new pump is bad?

Kevin Blown 95 TA

Sure seems like it. If you really want to rule out the regulator, maybe you can disconnect the return line, block it off, and deadhead the pump.

Injuneer

Seems like it would have been a lot easier to check the fuel pressure before totally reworking the installation.