Q: Engine not running correctly - high idle, little acceleration, p0400, p0300

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My idle is high, about 1,400 RPMS. Idles smooth (while still high) but when put into gear and with no acceleration is sputters. It accelerates without my foot even on the gas, although not quickly but for example, if I get to about 25mph it will continue at that speed. It accelerates very slowly. It almost seems like it just doesn't want to go into gear or that the computer doesn't recognize how much I'm trying to accelerate. Even when I put the pedal to the floor it takes a second for it to register and even then it only seems like the RPMs raise but the actual acceleration doesn't. I ran the codes and I'm getting a P0300 and a P0400. I have tried to adjust the timing and it seems like the distributor has to be clocked all the way to one side in order for it to run even somewhat smooth, the same is with the TPS. If I even try to adjust the TPS slightly the RPMs skyrocket. TPS, distributor, IAC have been replaced. For the P0400 I think it's the BPT but idk about the TPS/P0300 issue.

My car has 98000 miles.
My car has an automatic transmission.

Hi there. You might want to read this article about the P0400 OBD-II code which includes what it is, what causes it and the possible solutions. The EGR valve or solenoid might be the source of your high idle issue.

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