Ignore the user name, as I confused myself when creating it ...

Anyway, I have a 99 Blazer 4dr/4wd LT that has given me nothing but problems this year. My NYS inspection is up in 3 days, and I cannot get to the bottom of my SEL. Have so far replaced surge pump, one of the check valves (waiting to find time to do the passenger side check valve), have replaced all 4 fuel lines, on top of many other issues. All in all, its running great, and my gas mileage has improved drastically since replacing the surge pump.

Now, the issue I am having is that the surge pump is continuously kicking on and off, and no matter how I search it, I cannot find what would cause this to happen. It kicks on at start up, and does its thing for a few seconds, then kicks back off. However, while driving at lower speeds (most noticed between 30-35mph) it just kicks on and off and on and off over and over, then immediately the SEL comes back on. We've disconnected the battery after every repair to reset it, and it always comes back with the same code. So, at this point, I'm wondering if the other check valve being possibly bad is what could be causing the surge pump to keep kicking on and off. O2 sensors are good. I'm hoping my husband can fix/swap that out in the coming week, but in case that doesn't solve the problem, I'm looking for any other possible directions to look into.

On top of the SEL for the surge/check BS system (sorry, but really Chevy?), there's also an issue of getting gas fumes once the truck is turned off. Never notice it while driving, though I'm sure its there, but turn the truck off and the cabin is swamped with fumes. No detectable leaks, and no signs from underneath of where it could have been leaking. Walking around smelling has made us determine that the fumes are escaping from the rear of the vehicle, close to the gas cap/filler neck. Have replaced the gas cap, and the filler neck is solid with no signs of cracks or possible areas of leaking. Also, it seems to seep fumes once below a 1/2 tank - never when full. Last year the fuel pump was replaced, so I am not thinking its an issue with the pump. It is a NY Blazer - so all the common rust areas are pretty damn rusted, but again, looking underneath shows no significant rust damage to any components that you would suspect to cause a vapor leak.

Sorry for the book here, but I've searched high and low on the forum. I've solved most of the problems with what I've found, but I'm just not finding any help with these specific problems. Thank you in advance to anyone who read this and can help, seriously, I'm at my wits end and not diggin' the idea of being down my "grocery getter/kid carter," for any longer.

 

can you give the exact trouble code? Not sure what a surge BS system is

 

Surge BS system = surge bull shyte =D I'll be getting it re-scanned in the morning to be sure it is the same one this time, but off the top of my head the codes have been p0410, p0414 & p0440. As I stated though, we've replaced the surge pump, one of the two check valves (other one test fine, but, will be replaced over the weekend none the less), gas cap, and fuel lines.

The biggest concern that I have is not know what would be causing the surge pump to kick on and off continuously when driving around town.