1999 Blazer LS 4 door 4.3L (3 button 4x4)

22F outside
engine warm (Engine Gauge = 140F OBD II = 150F)

Engine = Off on tests below
key on = 60 and then drops to 55 very quickly
key off = 60 then drops to 55 very quickly
11:00 = 55
11:01 = 53
11:02 = 50
11:03 = 48
11:04 = 46
11:05 = 45
11:06 = 42
11:07 = 39
11:08 = 36
11:09 = 35
11:10 = 32

Engine On
car running (idle)
needle shaky but steady at 54
when Wide Open Throttle jumps to 62

pump looks like its working correctly but i bet my fuel regulator or something leaking in there.

I had been having problems with how the car has been running but i found out i havent been high enough temp to

go into closed loop
so that might be part of the problem
im gonna change out the thermostat and put a 195F i just got in.
i will report back with more data

I had been smelling raw fuel but i wasnt sure if it was out the tail pipe or if i had a leak in a line

somewhere

from the data above please reply to what you think about it.

 

Hmm. test it at the fuel filter,if it does this again then its the pump. if it holds,then id look at the regulator. its hitting 60,which is what it needs,but the 27 psi drop in 10 min is not good.


By the way,THANK you for posting actual info that we can use to determine problems. so many people lack this kind of info and expect us to fix it for them.

 

23 PSI in 10 mins

from key on (engine off) to key off = 55 then it drops to 32 in 10mins

but yea that would be a good idea to check (before fuel filter) but i guess i need to get a fuel pressure gauge.
i was at oreileys auto and they let me do it in their parking lot with no deposit.

man i really hope its not the fuel pump or the fuel regulator

just got the thermostat changed and also cleaned the EGR up and new gasket.
EGR felt nice...no problems with it as far as i could see

gonna see if i can at least get into closed loop (hopefully with new thermostat i can)