Codes 1171 and 1174
 

I have a 2000 DII with 113,000 miles. I’m getting error codes P1171 and P1174. I’ve replaced the MAF sensor and still get the codes. Occasionally with the above codes I also get a P0305 or P0308 and an occasional P1300. I’ve looked for a vacuum leak but have note detected any. Not sure how to detect such a leak other than looking and listening. It started off with about 100 miles between getting a code. The frequency is getting shorter and I get a SES light at about every 20 miles now.

Here is a list of the things that I have previously replaced.

At about 112,000 I was getting P0305 so with the mileage I have it made sense to replace all 4 oxygen sensors with sensors from Atlantic British. This fixed the O2 errors but did not fix P0305.

At 91,500 I had a slow coolant leak and was getting P0307 Cylinder 7 misfire codes. I took the heads off and took them to a shop to resurface and check the valves. Installed new head gaskets, 8MM Magnacore wires and Bosch +4’s. After I got everything back together I still had the misfire. I then replaced both coil packs. Everything was good until I got the O2 error at 112,000.

I got the truck at 81,000 and have always used premium gas. Any ideas on what I can do next?


Thanks,
BIG g