cranks and wont start
 

Ok, I see the chevy god's want me to buy a new truck.. lol. Ok just recently my 98 5.7 vortec 268K, never had this issue before, wont start when it rains. It will crank but wont start, I think it is flooding out. I say this because, when it happens, I pulled the plugs and dry them off and put them back in, and she fires right up on the first crank. Ive sprayed the wires down with WD-40 when it happened the first time and no help. So yes Im open for idea's...

Thanks

Sounds like the engine is running a bit rich and fouling the plugs.

https://chevroletforum.com/forum/gen...ng-rich-12852/

@ Go-Part Yea I figured the same, but why only on rainey days?

Sounds like condensation in the distributor

Cuz you have something responding to moisture in the air on rainy day, and that something makes ECM believe your engine runs lean, and it pumps ton of gas in?
You ever tried to read error codes, to start with?
Also, betcha you have crappy spark, and it simply does not ignite the mix. We have same model, I don't think you have dizzy, right? Solid ignition packs per plug, right? So wires are likely B-A-D, draining electricity and causing bad spark and so it goes.
Instead of (Why????) spraying WD40 onto wires, spray them with soapy water. If you hear crackling, well, here ya go...

@ Ukrkoz.... No I do NOT have "Dizzy" lol... I will trying soapy water on wires to check for bad wires. I do not have any codes, CODE FREE... If that is the case, which I will check. I will replace all that is involed again... Cap,rotor,plugs, wires..
Thanks

@ Kevinkpk............ Thanks

i had the same issues I have done all above what u comment on still having issues but I found ways to by pass this turn the key on listen yr fuel pump primed lve they key on hold yr foot 3/4 ways down then started it but hold it till it started shaking and then fires up then slowly let off the gas it worked everytime and yr right the ecm is confusing the computer error code causes to flood out thats what i did with what i said i have replaced almost everything and still does