I have a 94.5 powerstroke all stock for now and i went to get emissions and failed because the check engine light came on... usually ill drive for about 30 min without the light then it come on often while "getting on it"... i ran the codes with my edge evolution and P1211, P0472, and P0470 came up when the check engine light is on, AND when its off... so i have no idea which is tripping the light. P1211 is ICP Not controllable- pressure above/below desired. P0470 is back pressure sensor fail and P0472 is low back pressure i believe. my question is which one is tripping the check engine light, and what i can do to fix it so i can get my truck registered. oh and the codes come up wether the programmer is on the truck or not. and rarely itll throw up a PCM Mermory reset code or something... but it doesnt happen very often so im not too worried about it. (usually happens when im driving and plug in the programmer to check codes... it cause the motor to caugh hard when i plug it in while driving too)

im going to start by cleaning the back pressure sensor line and sensor. if that doesnt fix those codes ill need a new sensor...

i have no idea where to start with the icp noor what it really means... ive heard its low or high hpop pressure and can be damn neer anything...

 

I had the same code P1211 I changed the cam sensor and the ERG sensor at the same time Truck is running normal . I dont really know wich one fixed it cause I changed them both at the same time . Or if either one was the culprit I was guessing at the time . But I havent had the code since, and I also have the Edge evolution chip . you might try it .

 

should have checked if you had a cat before you did emmissions

 

There is the EBP sensor and tube that runs from the back of the HPOP reservoir and tube runs from it to the exhaust manifold. Maybe that is what he is talking about. There is no EGR on the OBS's but the funny thing is that in the Ford parts manual that tube is called an EGR VAL tube. And it must be kept clear.

 

a bad ICP sensor will cause this issue... Check the connector for oil inside of it.