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Hey I bought a 1994 Chevy C1500 with a 5.7L 350 TBI a couple of years ago. Just hit 200K two months ago and everything was great until now. The truck idles great the problem is that when I try to step on the gas the truck almost turns off and then takes off (if it didn't turn off). I have let the truck take off by itself and den slowly step on the gas. Then when im at cruising speed if I step on the pedal all the way the truck will take of well until it hits about 3800 RPM its like its not getting enough air or fuel.

I just changed the fuel pump, fuel filter, TPS, and Air Filter. I'm thinking it might be the fuel injectors but am not sure. I don't want to pay $250 and it not be the problem. Thanks for the help in advance.
 

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I'd check the fuel pressure just to be sure. AutoZone & a few others will loan you a FP guage if you leave a $$ deposit.
 

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A couple things come to mind here. First of all, take a good, hard look at your ignition system. The coil, plug wires, distributor cap & rotor all can cause the problem you're describing, especially if that stuff is original. Also, as mentioned above, it might be well to drive it with a fuel pressure gage attached and make sure it's getting enough fuel. Finally, take a look at the intake air tubing that goes into the air cleaner assembly to be sure it isn't collapsed or plugged with debris of some kind.
Good Luck and God Bless
 

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Discussion Starter #4
Thanks for the help I checked the coils, plugs, distributor and rotor, and all were good I will see if I can find the Fuel Pressure Gage to check it. Again thanks for the help.
 

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Well I checked the Fuel Pressure and it was on point. I also forgot to mention after the truck warms up a little bit the oil pressure is extremely low at idle. I thought maybe its the oil so I changed it and put Quakerstate 10W-40 and its still getting really low
 

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What is really low? it isnt uncommon for the 350TBI to have around 10PSI at idle. I want to ask if the check engine light is on? i doubt it since its OBD1 but gotta ask. Also what shape was the inside of the distributor in? rusty at all? and the crank sensor? Those are known to get weak and wont advance the timing enough and give the exact conditions that you are talking about.
 

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Be sure the computer ground wires are all clean and tight. I've seen lots of trouble with the one that goes on the thermostat housing bolt. I usually move that one to another, cleaner location.
Good Luck and God Bless
 

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Replace the ignition coil, my truck was doing something similar to that, and I have a 94 chevy like yours. It's the ignition coil, if you've never replaced it, which, they tend to start going bad around 150k, then replace it, it's like $40 for a performance coil.

Also, you might be due for a throttle body cleaning, just take it off, and spray it clean with throttle body cleaner, it's something simple you can do yourself. To depressurize the fuel system, take the fuel pump fuse out, and then turn the key, and you're good to go.
 
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