no acceleration

[cancuk]

2001 chevy silverado 4x4 4.3 liter standard transmission

So where do I start. Driving down the hi-way and the truck felt like it lost its power. While in fourth gear it did not want to accelerate past 2000 rpm. I pulled over to check any codes. P0101 & P0304. Cleared the codes and went on my way. Truck drove normal...for awhile. About 45 min of driving started to happen again. So I limped back to the nearest town. Replaced my MAF (PO101) as directed by my mechanic over the phone. $230 later did not fix the problem. If anything it seemed to get worse. Unplugged my MAF as directed and limped home. While driving home the truck started surging and smelled like exhaust ( gas like smell but not quite ). As well my oil pressure started fluctuating low to normal. My oil was darker, not black, but much darker by the the time i got home. The oil level did not change. Last but not least, by the time I got close to home the acceleration was gone in third gear and then second. Before, I had somewhat normal accel. in the lower gears then not. The problem started about 1 mile after I filled up. Sounds like a coincidence to me though. I know that's a lot but any suggestions would help!!!

 

[Jim Fairbanks]

Since it happened after you filled up I would try some HEET in the gas and see if you got water in the gas.....then I would check the catalytic converter and make sure it is not plugged up.....Jim

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[cancuk]

I'll try that. but knowing my luck that would be too easy. it seems to me its too coincidental and progressively losing power under load sounds way more expensive. but start small right. thanks for any input

 

[ironhead]

The P0304 indicates a #4 cylinder misfire. This is likely the original problem. Driving with a misfiring cylinder will dump raw fuel into the exhaust, which can destroy the catalytic converter. If the converter starts to plug up, the amount of air being draw into the engine for a given rpm and throttle opening will drop. This will cause the computer to set the MAF sensor code. The longer you drive with a misfire, the more restricted the cat becomes, and the less power you have. You need to do a backpressure test on the converter to verify it is restricted. If it is, it will need replacing. VERY IMPORTANT, you need to find and correct the cause of the misfire or you WILL destroy the new converter in a very short time. It may be as simple as needing a tune-up. It usually is something very simple, that left unresolved, causes major problems down the road.
Guy

 

[cancuk]

Good information guys. Here is an update. Took the truck to my mechanic and I need a new fuel distributor (spider). Apparently it was pissing fuel. Does this jive with what the symptoms I stated and if so how easy is this fix. I just got the truck out of the shop for the "GM intake gasket" fix in December. Could these be related? I have kept up with all my regular maintenance. Plugs, wires, cap, rotor and such. I appreciated all your input.

 

[Jim Fairbanks]

That could be your problem if it is leaking...You might be able to smell fuel in your oil if it is leaking a lot...Jim

 

[cancuk]

I'll try that. My oil did get dark on my way home.

 

[cancuk]

so I changed my fuel distributor (spider) on the weekend. same problem. smells like gas and won't accelerate normally. the surging is gone but I'm am still getting a random misfire(P0300). Any ideas on what would create the gas smell.

 

[cancuk]

Update!!! pulled my O2 sensors out of two cats. Runs with normal power & acceleration. Finally figured it out. I hope.

 

[Jim Fairbanks]

Sure does sound like the cats are plugged.....Ironhead was right on with that it sounds like....Jim

 

[ironhead]

Even I get lucky once in a while!
Guy

 

[Jim Fairbanks]

LOL..funny...Guy....don't you just love getting LUCKY?........LOL....Jim