'03 Avalanche problems

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First, the codes:
P0101 - P0101 MAF or VAF Circuit Range/Performance Problem P0300 - Random/Multiple Cylinder Misfire Detected P0576 - Shift Solenoid B Performance or Stuck Off
The symptoms:
Rough idle, very little power.
What happened:
I was driving at highway speeds yesterday with no issues. After a stop light, I noticed a slower than normal acceleration. About 10 miles later I came to a small hill, nothing large, just an overpass. The truck began to decelerate and MIL began flashing. I took the next exit and barely made it up the ramp, engine running very rough and very little power. I stopped the truck and shut off the motor. I checked the fluid levels and all was fine. I restarted the truck and decided to drive 1/4 mile to a relatives home.
I returned today and retrieved the codes listed above. I then cleared the codes and restarted the truck. It was still running rough. I only got the first 2 codes and no flashing MIL. I then drove down the drive and got no additional codes. I then drove it down the short road to a small incline which was too much for it to overcome and caused the light to begin flashing again. By small, I mean the intersection was raised about 3 feet higher than the road I was on. This 3 foot rise is over a length of 10-12 feet. I then got the last code again.
I don't even know where to begin with this. Fuel filter, fuel pump, computer, sensor? A year ago I would have just taken it to a shop and asked them to fix it. Unfortunately, it's now my grocery money that I have to work with. Ant ideas or similar experiences? Thank you so much.
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Those codes and symptoms could be the intake gaskets......seen this before.
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Is there a quick easy way to check this? Ha-ha, nothing is really quick and easy I suppose.
Thanks
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James Horn wrote:

Well a bad MAF/VAF signal can cause the symptoms your seeing.
Does your scan tool allow you to read live data? If so I would look at the MAF/VAF signal and see what you have in relation to the TPS signals.
--
Steve W.

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Unfortunately my scanner only reads and clears codes. I do have software for my laptop that will do this, But I don't have a cable.
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The last time I experienced your symptoms, one of my plug wires had burnt through. I doubt that's your problem, but they always say check the easy things first ;)
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I did look at them, even in the dark looking for arcs. They all appear to be good, I replaced them all at just under 100,000 miles, it's at 109,000 now so they should be good, but you never know. I did get random misfires which led me to believe it's something before we get to that point.
Thanks
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I know it is a PITA, but if you still have your old ones, maybe a temp swap out for a no cost test. ??

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That certainly can't hurt. I'm not going anywhere anyway.

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That is an excellent idea. I will look into it today.
Thanks

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Hess Gas?

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Ha-ha, no. Speedway. I filled up earlier in the week and used 3/4 of it before the problem developed. I am going to change the filter tomorrow, can't hurt.

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On Sun, 07 Jun 2009 22:41:31 -0400, James Horn fired up the etcha-a-sketch and scratched out:

Seen the other posts too.
Some guesses - fuel injectors? Cat clogged? O2 sensor(s)?
What do you have the 1500 or the 2500? Any mods?
--
perfectreign
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Can a clogged Cat cause an engine to run rough??
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In a Heartbeat!

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Are you sure?
I have seen a lot of clogged cats, and even stuffed a few potatoes over the years, but I have never seen an exhaust restriction cause an engine to run rough.
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Simple test, remove it and see.

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Simpler test, take any vehicle running well, and stuff a potato in the exhaust, see if it runs rough.
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On Wed, 10 Jun 2009 12:31:00 -0500, Tim fired up the etcha-a-sketch and scratched out:

Writing from experience, yes.
Well, actually, the clogged cat wasn't the original root cause, but it sure messed stuff up.
I had a '95 Jimmy 4x4 with the 4.3L V6. The injector in one or more cylinder got clogged and I started experiencing misfirings at around 70K miles. (The injector for this truck sucked!)
After I got the injectors replaced, I was still having issues. I figured the O2 sensors were fried and - upon checking - that was true. Replaced them.
Next it still was running rough. It was the cat.
Because of the other issues, the cat got clogged and needed to be replaced. Did so at about 120k miles and all was well after that, except for the 4x4 system going out. :P
--
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