Q: I changed the motors and it starts and runs great at low rpm. If I try to accelerate it sputters and falls on its face.

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I bought this pickup with a blown not or I got a motor from a salvage yard and put bearings oil pump rings and used the head and intake that waz on the motor in the truck it will start and run great at low rpm if I try to give it over a quarter pedal it sputters and falls on its face I've changed all the sensors except the fuel pressure sensor in front with the vacume hose on it on top of throttle body their is one hard vacume line not going to anything and a box that looks like two vacuum hoses needed to go to it has electrical plug also I am not sure if it's the map sensor or goes in line with the egr valve any ideas

My car has 167459 miles.
My car has a manual transmission.

Hi there. Check all of the vacuum lines to the engine and make sure that they are all connected or plugged off if they are not needed. Check the spark plugs and see what condition they are in. If the engine was at a salvage yard, its possible that the engine may have been sitting for a while and the spark plugs may have rust on them. I recommend putting in OEM spark plugs and new spark plug wires with a new cap and rotor. If you need further assistance with your engine stumbling, then seek out a professional, such as one from Your Mechanic, to help you.

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