jack rabbit55

i have a ls motor in my 1955 chevy, for the last 3 times when i washed the car it wont start afterwards, normally i can here the fuel pump for 7-8 sec or so , when it wont start i only here it for a sec , the first time i check everything i knew to check, fuel pressure and volts i gave up and after about 3 to 4 days it started right up , the second i washed i was careful when washing it it happen again i let it set fora few days it started up again ,now the third time here i am ,wont start , each time it cranks fine, but i only here the fuel pump for a sec not the normal 7to 8 sec or so. now what could cause this , i have replaced both relays and check all fuses for being wet or damp, i have check my ecm the plugs ( red and blue ) are dry,i even removed them and installed them back. i hate to wait until it gets ready to start. where do i start to look ?
thanks for any help

G Atsma

When washing the car, are you getting the motor wet?
With the electronics involved, that should be minimized as much as possible.

jack rabbit55

i am not raising the hood and not spraying toward the motor

jack rabbit55

i jump out the relay and made the fuel pump run for a long time and it started and run , turned it off and no start again took the plugs off the pcm and reinstalled them and it started and ran waited a few minuets and again no start , so i am going to start with 2 new relays and go from there, thanks

jack rabbit55

i looked and this what i bought back in may of last year

Che70velle

iTrader: (6)

Did you utilize the dialectic grease? With the smaller than normal terminals that this particular relay has, any moisture in there would cause issues. I’d be tempted to replace this with an automotive style relay setup with normal sized blades. They will be more robust than what your using currently…

jack rabbit55

changed relays to fuel pump and no start

the_merv

iTrader: (88)

Sounds like water might be getting in the Fuse Box if you have one under the hood that might be in the wrong spot.

jack rabbit55

yes i used the grease

jack rabbit55

everything was dry , i checked all fuse and they were good

jack rabbit55

went out last night and all of sudden it started, i dont know whats going on, i installed ne relay even went back and tried my old one still started, i think it might be a my key switch