Got a real issue with gas
#21
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Well for one your charcoal canister is clogged or a return line is clogged. It's pretty common since the charcoal cans only have a shelf life of a few years on a DD. You can rather find a gas cap that fits the threading with a vent built into it (since the LT1 cars have a charcoal can they don't have vented caps) or replace the charcoal can... I'd just get a vented cap and see if that fixes it.
Poor fuel mileage can be a bunch of things. What gears do you have? What do your plugs look like? Do you have anyway to read the O2 sensors? How do your O2 sensors look? How does the car idle? Does it feel sluggish/down on power?
An improperly vented system can cause it to run funny but it isn't causing that kind of fuel mileage.
Poor fuel mileage can be a bunch of things. What gears do you have? What do your plugs look like? Do you have anyway to read the O2 sensors? How do your O2 sensors look? How does the car idle? Does it feel sluggish/down on power?
An improperly vented system can cause it to run funny but it isn't causing that kind of fuel mileage.
Check the two small hoses under the radiator cap. One is the steam pipe return line, and the other goes to the overflow. The one going to the overflow tank is supposed to be on top. They are the same size hoses and it is a common mistake to switch these two on accident when replacing the radiator.
#24
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A charcoal canister has vacuum lines running to it. When the can clogs or the charcoal starts to break apart and clog those vacuum lines, what happens to the gas tank and fuel supply?
Have you ever taken a non vented cap and stuck it on a vehicle that was designed to use a vented cap? You will get the same results as a clogged charcoal canister/vacuum line; hard starts, rough idle, power surges. It will also stink like fuel and cause the "hissing" gas cap sound.
#25
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I must have missed where I said the charcoal canister was affecting his fuel economy. I actually said the exact opposite.
A charcoal canister has vacuum lines running to it. When the can clogs or the charcoal starts to break apart and clog those vacuum lines, what happens to the gas tank and fuel supply?
Have you ever taken a non vented cap and stuck it on a vehicle that was designed to use a vented cap? You will get the same results as a clogged charcoal canister/vacuum line; hard starts, rough idle, power surges. It will also stink like fuel and cause the "hissing" gas cap sound.
A charcoal canister has vacuum lines running to it. When the can clogs or the charcoal starts to break apart and clog those vacuum lines, what happens to the gas tank and fuel supply?
Have you ever taken a non vented cap and stuck it on a vehicle that was designed to use a vented cap? You will get the same results as a clogged charcoal canister/vacuum line; hard starts, rough idle, power surges. It will also stink like fuel and cause the "hissing" gas cap sound.
And no, I do not know what happens when a charcoal canister "clogs." In the 100k miles I have driven my car, mine has never clogged. Nor did it ever clog in the 90k miles it was driven before me.
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from what ive discovered; while idling in park my rpms jump from 715 to 743 back and forth, sometimes falling to 688 on the dot. the thermostat and coolant sensor are within 10 of eachother, and my o2s seem in order too
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dont worry moe change it every 3k doesnt smell like fuel.
my stepdad has the snapon modis it comes preprogrammed with all kinds of tests that it can perform pretty sweet i unplugged the cts and the temp stayed the same
my stepdad has the snapon modis it comes preprogrammed with all kinds of tests that it can perform pretty sweet i unplugged the cts and the temp stayed the same
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Also, if you have headers on your car, check the harness that runs down by the passenger side header. I had a few of these wires get to close to the header a couple of years back, it melted probably 4-5 wires, and threw a MAF code. The car ran like absolute **** until I got it figured out.
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checked the wire harness no dice it was secured nd heat taped. now heres something ive noticed for a while theres quite a few sensors unplugged all throughout the engine bay anywhere i can find a diagram of them?