Poor running 92 Suburban

I have a 92 GMC k1500 Suburban 5.7L with 208K on it, it has started running very poorly, it starts very very hard when cold and will not idle until I run it at a fast idle for 10 to 15 seconds, it seems to not have near as
much power as it did. When it is warm and started it will not idle and when you get it in gear and take off it will surge really bad for a minute or two before it runs smoothly again, it does not do this every time however. It has set code 44 many times since this started (lean exaust), I have replaced the O2 sensor and put new plugs in it. Anyone have any idea what I might be facing here?
Thanks,
Tim
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Could your fuel pump have gone bad. Is it a throttle body or Multi Port.

running
when
two
replaced
be
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I
It
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running
when
two
replaced
be
vacuum leak.
Check the bolts on the throttle body, make sure it is tight to the intake manifold. Also check all of the vacuum lines and make sure the EGR valve is not leaking.
good luck, mark
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I
It
is
Doubt it; vacuum leak would be consistent the whole time he's driving, not intermittant.
Doc

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intake
valve
Ok, I had a similar problem in my suburban and the dealer replaced the tbi to manifold gasket. They said they thought it was sealing when it warmed up and when cold everything contracted breaking the seal...this was on a 91 which should be the exact drivetrain. Thanks for the help I appreciate it. :-)
mark
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Doc, I have changed the fuel filter on it, I forgot to mention that on my original post.

running
when
two
replaced
be
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had similar symptoms in a 93 S-10 4.3
needed a fuel pump
G

I
It
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until
as
and
or
might
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quick test: take one of those 'heater hose clamp-off' type vice grips and clamp down on the return line while watching the O2 sensor readings and injector pulse width on a scan tool
you will see (at idle) the IPW return to around 1.2 mS and O2 go from 'lean' to switching back and forth from rich to lean if the pump is on its way out
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fuel
so
all.
I filed that message for a rainy day G, thanks. Beats the shit outta adapting the damn line to get a pressure guage in there.................
Doc

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Well, I am going to change the fuel pump tonight, I will post results when done, thanks everyone for your input.
Tim

system
as
and
its
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Well I changed the fuel pump and that fixed it, runs like a new one now. I was really dreading the job but it wasn't that bad, 2 hours and I was done. Thanks for everyone's help.
Tim

at
anyways
and
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done.
Good for you. You dropped the tank and reinstall everything in 2 hrs.?. I am impressed. :-)
mark
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Must have been an empty tank.

I
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I
Must not have gotten into the beers whilst working on it eh? A 2 hour job usually takes me 4-5 due to numerous beer breaks............
Doc

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I always try and finish the job first then double up on the beer to make up for lost time. Yep, the tank was empty, in fact I ran out of gas on my way to the shop where I worked on it, a friend of mine has a nice shop with a lift so that made the job much easier.
Tim

now.
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I have never been able to do the beer thing while working on trucks. Always have my buddy jim beam with me.

was
job
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one
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