hi i have 99' 2wd Lt that i put a Delco fuel pump in back in april. Prior to that i changed the filter thinking that it may solve the hard starting every 4 days. Not successful but i gained alittle more mileage. With the new pump installed the truck started on contact no cranking then about 3 months later i got fuel ant an Arco that was bad. It started crankin funny again but this time it was on full tanks only. I ran the bad gas out and it was fine the rest of the summer. Now since late august it starts funny every 6 starts on a full to near full tank.(by the way i run chevron mid grade only, vegas gas sucks). Im stumped. the blazer has never died while driving on me ever but has a delayed start. . I had the fuel pressure monitoredover two hours of sitting then starting andand she was steady 59 to 65.Any help would be appreciated.

 

Have you run any fuel injector cleaner through the system while you were working the bad gas out of the system? I'd start with the cleaner through a couple fill-up cycles and see if things clear up. If not start with the easy stuff, like cleaning the MAF air sensor, changing the fuel filter (maybe no so easy but do-able), hitting the intake with carb cleaner, etc....Good Luck.

 

Thanks, i cleaned the Maf before i changed fuel pumps. The only thing i did not do was change the fuel filter after i recieved the bad gas because it only had 1400 miles on it(now it has 3500. I also have run chevron and STP fuel injector cleaners. and i Seafoamed it in july. Thanks for your help again, i did research all night and i came up with bad Fuel spider due to the fact that it is originaland /orposs. bad cat coverter because in the morning u hear it rumble through my 10 series flowmaster and it has a slightring at normal operating temp. I am going to stick a new filter on there to se if that helps. any before i do anything major other than the cat.

 

Just a crazy thought here, but I wonder if the fuel filter/strainer on the fuel pump is compromised. The strainer is a very finely meshed filter that keeps particulates out of the pump. Anything getting past the the pump strainer should then be caught by the fuel filter under the vehicle. Anyting getting past the fuel filter has a clear shot to the spider and injectors. The spider and/or an injector(s) could be compromised. You could also suspect the FPR (fuel pressure regulator) as well.

When you had the fuel pump replaced, did you have the tank cleaned and flushed? That is a necessary part of the pump swap process.

 

thanks junkmonkey. I seafoamed the thing today and it has a smoother idle which it basically had. it seems to have a better start so far. i do hear the cat rattling alittle so that could be soomething. As for cleaning the tank i did not clean it at all. i ran the tank down to nothing with Gumout on a 1/4 of a tank thats all. The odd part about the spider is that i dont know if it has been changed or not due to the fact that the upper plenum looks about a year old. Tax time i am upgrading to the new MFI unit.