I'm sorry if this seems off-topic being a 4X4 group, but I couldn't find
anywhere else to go regarding this issue. If you know of a more appropriate
group please let me know.
I've got a '97 C-1500 that recently has been getting slower to start. The
engine cranks good and hard, but no start. I'll give it a good 5-10 seconds
of cranking, turn off the key, try again, and Vrooom - it starts right up.
(It seems to have gotten worse over the last few weeks). I've ruled out the
battery connections, battery and alternator. Non of which by themselves
should be the culprit I would think. I'm not thinking the ignition switch
because sometimes I can crank it and after about 5-7 seconds it will start
(I'm going to check voltages at the ECM fuses later on today). I can drive
it and then turn it off and it will start up again right away, but if I let
it set a short while (10-15 miniutes) it is back to the same condition.
Anyway, I was wondering if anyone has seen this particular symptom and if
anyone has a possible cure or starting point for me to start investigating
About six months ago I had a simular problem with long cranking start-ups
too. To start troubleshooting, I hooked a pressure gage up to the fuel
pressure tap and noticed that my fuel pressure was leaking down when the
enigine was off (at about 55 psi while the engine was running and then after
turning it off, the pressure would slowing drop down to about 8 psi in about
10 minutes). My problem turned out to be *too much* fuel. caused by a bad
*Fuel Pressure Regulator*. It has a vacuum hose on top of it that goes into
the air intake plenum.....and gas was leaking into it from that vacuum hose
hooked up to the Fuel Pressure Regulator. When the engine was off gas
leaked into the air-intake plenum and this is what caused the long cranking
to start the engine. I actually stumbled on the problem when I was checking
the 8 new fuel injectors that I had just installed because I believed that
my problem was a leaky fuel injector(s). While I was in the middle of the
"replacing the fuel injectors" procedure and checking them for leaks (with
the intake manifold still removed). I turned the key on (ignition only) to
pressurize the fuel rail to see if I had any leaks in the fuel injectors or
"O"rings when BINGO!....there it was. Fuel was pouring into the air intake
plenum from the vacuum hose coming from the Fuel Pressure Regulator. I
installed a new Fuel Pressure Regulator, completed the assembly.......and my
problem was gone.
You're looking in the wrong places for the problem Scott. If the motor
cranks fine, the battery, alternator and cables + IGN switch are just fine
as well. Your problem is fuel, spark, compression or timing, most likely
fuel (either too much or not enough). Next time you start it, crack the
throttle plates about 1/4 open and see if she starts quicker.
Thanks for the info guys..
Here's what I've got so far. I'm thinking that it IS the ignition switch
because I have noticed that when I crank it and then turn the switch off
completely that it seems to start right away. Also, I've noticed that when
the driver's door is open, the buzzer doesn't come on all the time, AND the
other night the interior light was coming on (if at all) then going off, and
coming back on again. The head mechanic at the Chevy dealer had mentioned
the switch, backing up what I have seen on the groups about this year truck
having had that problem. I mentioned the battery and alt Doc because I have
seen and noticed that the battery can supply the starter and other electical
systems simultaneously...creating a crank and no start condition (not sure
if that's true). Again, this weekend I'm hoping to check voltages at the ECM
fuses per the mechanics suggestion to see if the problem is the ig switch.
Like you guys said, it could be either too much or not enough fuel. I'll
check the fuel pressure reg next. It's either that or the damn things
haunted! :) I'll keep you informed as to my progress. Again, thanks for the
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