94 F150 4.9l I6

[FORDMAN41291]

ok, so I've had this problem for quiet sometime, I ant figure out why the check engine light won't turn off. when i first start the truck the check engine light doesn't come on. but when you actually start going and after it warms up it turns on. it also had a very high idle at start before I disconnected the IACV. now it idle normal. so you start the truck and you let it sit there for however long and the check engine light doesn't come on until you start to give it gas. aka use the accelerator. I'm thinkin in the TPS. but I could be wrong. I'm also thinking it could be the EGR valve??? any help on this situation would be greatly appreciated. also. it doesn't throw any code except for transmission not in neutral or park. its a 5 spd. M5OD.

thanks.

Ken.

 

[Optikalillushun]

first things first, SCAN THE CODES. we have no idea what the codes are and throwing ideas or parts around wont solve it.

 

[FORDMAN41291]

if i did not state above, it is not throwing any othe codes except for a soft code stating transmission not in neutral or park (its a standard transmission) today I replaced the TPS and I'm able to pull up a hill now without downshifting out of overdrive. I'm thinking it's the O2 sensor now that I'm thinking about it. high idle I now know is from the IACV... any other suggestions are/is appreciated as I try and resolve this problem.