cisurfer

So I've been chasing the p1131 and 1151 lean bank 1and2 codes for months. 02 sensors are year old. Brand new frpp manifold. New header gaskets and intake manifold gaskets. Checked vacuum lines. Deleted egr. All new gaskets for iac tb and plenum. Everything has been checked over for vacuum leaks. I added a pcv catch can last week. As of last night I am now throwing 0174, 1130 1131 1150 1151. All system too lean codes and bank 1 and 2. I'm lost. If I clear the codes they stay off until I let my car idle for over 2 mins then the roma start going from 500-800 and sometimes the car will drop to 50-100 rpms and jump back up. Any input? Fuel system?

uberstang1

This sounds similar to what I was expereince when I deleted my EGR. The car started throwing lean codes for both banks and the idle became iratic. I called my tuner up and he emailed me a new tune with the EGR parimeters deleted, I uploaded the tune and never had a problem since. What mods are on the car? First thing would be to check the fuel pressure at the rail.

cisurfer

My tune I had before I deleted the egr was already set to off so it isn't the tune. I also uploaded the stock tune and it threw the same codes along with the egr codes. Everything in my sig. People say it could be then LT headers but I've had them for a good amount of time with no problems. Only thing I can think of is my plenum and tb. I striped the bottom threads for the iac so I jb welded a insert into it. New gasket and it seems sealed as it should be. Only thing I'm thinking is the seal on the tb by the tps. They use o rings on the shaft for the butterfly and they maybe dried up but nothing else makes sense. How do I check fuel pressure?

uberstang1

You can buy a manual fuel pressure gauge which taps into the shreader valve on the fuel rail. Any kind of bad gasket on the intake manifold or TB would probably make a sucking/vacum leak kinda nosie.

cisurfer

Also just remembered when I was messing with header gaskets I bent the hell outta the dipstick tube. I bent it back but I'm thinkin maybe it got cracked somewhere. I'll try replacing that because that is a cause possibly

uberstang1

A cracked dipstick tube? No that can't do anything but cause a leak depending if the crack is close to the bottom. PS: You have no sig.

cisurfer

On the chart on cliffys site it says that could be a cause because air can enter there and travel into the pcv system into the intake. I have a sig but since I'm on my iPhone with this thread it probably only shows on my comp at home

cliffyk

+1 on turning off the EGR in the tune. It's just one setting, EGR Selector Switch (needs to be set to 2), however it affects most of the closed loop fueling calculations.

Also, check the f/p as uber' suggested--have you ruled out exhaust leaks as well? In closed loop mode they can cause lean indications.

Do you have a wideband O2 system--is it actually lean?

cisurfer

No I am buying a sideband with my Xmas money actually lol but the egr had to be turned off because I get no egr codes but when I put it back to stock the egr codes show. I will check the f/p. And I changed my exhaust gaskets with new ford ones about 3 months ago. 99% sure they aren't leaking. I have a tick but it's my head valve guide. Been there since I bought the car with 48k now it has 117k.

cisurfer

Once I get out of basic for the coast guard I'm going to get a truck for a DD and pull my motor and rebuild so hopefully if I can't figure it out before then that will take care of the problem haha