[Dfeeds]

I've been trying to figure it out and I've not had much luck. Just recently I got a new exhaust (MAC L/T's, 2.5" tubing, flowmaster 40s, O/R H-pipe). I installed two MIL eliminators from AM on the back o2 sensors as well.

My issue is this, when I first start the car (winter so it's cold) it'll idle at about 1500 for about 30 seconds or so (normal) then drop to below 1000. It'll sit like that for a couple of minutes then it'll drop even lower and start to sputter like it's going to die (but doesn't). If I let it sit for another 3-4 minutes or so it will go back to normal and everything will be just fine (driving wise as well). However, if I try to drive before that alloted period of time, my car won't go anywhere. I can rev the engine but as soon as I shift into gear it doesn't do anything no matter how hard I step on it. My trouble shoot (if I had to move) would be to shift into neutral, rev it high (up to 2k or above) and shift into gear which solves the problem, until the RPMs drop below 2k then it all happens again.

I also had my codes pulled for the CEL and I got p1152 and p1132.

P1132: lack of bank 1 02 at its rich limit
P1152: lack of 02 switches, bank 2 senors 1 - rich.

Both have a probable cause of either high fuel pressure, EGR stuck open, or engine mechanical condition. Considering I had no issues before the exhaust I can probably rule out the latter and first, so could it be an issue with my EGR tube?

[dgt_mustang]

Funny...i have the exact exhaust setup as you, +2 high flow catalytic converters and my car does the exact same thing but in less time increments, mine will act like its going to stall for about 20-30 secs and then go back to normal, sometimes while driving it will suddenly just feel bogged out and no matter how far down the gas pedal goes i dont go any faster. it will resolve itself after like 30 secs but its awefully annoying. I'm looking at my exhaust tomorrow, i think my cats got banged up and are clogging, i bottomed out a couple of times on speed bumps which happens to land right on top of them. sorry my post was lengthy and not problem solving.

[Dfeeds]

It's fine. At least you know exactly what I'm talking about. I wish I had time intervals of that. It's rather annoying having to wait 10 min to go anywhere (especially when you get off of work).

I don't have cats though so that's odd and could mean it's something else for you? I'm still going more towards the CEL being a huge key factor in this whole thing. Is yours on by chance?

[mcqueen]

I found this on several forums with people pulling the same 2 codes:

Electrical - Short to VPWR in harness or HO2S - Water in harness connector - Open/Shorted HO2S circuit - Corrosion or poor mating terminals and wiring - Damaged HO2S - Damaged PCM Fuel System - Excessive fuel pressure - Leaking /contaminated fuel injectors - Leaking fuel pressure regulator - Low fuel pressure or running out of fuel - Vapor recovery system Induction System - Air leaks after the MAF - Vacuum Leaks - PCV system - Improperly seated engine oildipstick EGR System - Leaking gasket - Stuck EGR valve - Leaking diaphragm or EVR Base Engine - Oil overfill - Cam timing - Cylindercompression - Exhaust leaks before or near the HO2S(s)

It's basically a list of everything that could be causing the issue, and I believe it is straight from a Ford service manual. A guy on another forum suggested starting by checking that the connectors (of the upstream O2 sensors) are clean.

[stephen]

P1132 means there is a lean condition detected.

I believe one cause can be a leak into the exhaust upstream of the sensor. Another
possibility is that with the modified exhaust the sensor is at a different distance from the engine.

I would say check for an exhaust leak and replace the upstream sensors.

[Jessn29]

dont worry about the high idle in the morning. i doubt that has to do with your new mod. mine is high too and also drops back down after a min.
but the low might be your running lean like everyone else said.
maybe get a tuner to get a higher imput of fuel....idk

[Dfeeds]

I don't think there is any leaks but the sensors are definitely in a new spot. The stock position is right at the end of the exhaust manifold which is only a few inches away from the block if I'm not mistaken. The new location is at the end of the L/Ts and that's a considerable distance away.

What puzzles me though is that the car runs literally just fine after letting it sit for a few minutes, if there was a leak of some sort wouldn't it be constant, or does the engine "learn" to compensate?

[TheAntiricer]

i didnt believe it at first, but someone else is here was having the same problem after getting LTs for a while i didnt think the new place for the 02s would make a difference but whit you is like the 3rd person i hear having this problem. ...... does anyone esle have this issue after getting long tubes? your more than welcome to enlighten me.

[Dfeeds]

Not to revive an old threat but I figured since it wasn't answered and there were people with the same issue I might as well post the solution. It only needed new o2s... but here's why if anyone is curious:

Sensors need to reach a certain temp before they are actually "read" by the computer. Before the computer gets a signal from all sensors it runs in something called an "open loop". While in open loop the computer attempts to guess what the engine should be doing, now because my car isn't exactly stock that causes problems. Being that my old o2s were probably old and carbon filled, that and being so much farther away from the engine block, they simply weren't heating up. The result is that the sensors are stuck at "lean" and the computer is trying to compensate. The computer needs the reading from every o2 sensor in order for it to enter a "closed loop" in which the engine operates on its own and operates properly based on the air/fuel intake, etc.

[6ER THEN I 8ER!]

well you really only need the front o2 sensors to tell the car how much gas to give...the rears really only tell the car if the cats are there or not. i wish i had saw this thread a month ago i could have just told you the issue. There was a newer member on last night with bad idleing issues after new full exhaust was installed. it's fixed now

[Dfeeds]

Yeah, the fronts were the ones that weren't giving a signal which caused everything. If it were the downstream I wouldn't have had all the hassle...

I know most of you probably know all this but I figured I'd share what I learned about the computer just in case someone else was looking around