A couple problems...need your help!

Hello all,

I know I don't post much but I've been busy with the new house still. Anyway, we were coming home from dinner last week and I got 2 codes that popped up on my Aeroforce at the same time. They haven't come back since I cleared them.

P1811 Max Adapt and Long Shift

P1133 Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 1 Sensor 1

I understand the P1811, and I have a shift kit on the way for the time being (something I wanted to do anyway). Since I have a tuner now, which I have not messed with, would it do any good whatsoever to change the shift pressures even though I'm getting that code? Seems more of a mechanical issue since the computer can't seem to keep the shift times where they should be. A PCS in my future?

The P1133 has me a little puzzled. My O2 sensor is not old by any means. I believe it is about 3,000 miles old and a Denso. Still a possibility of it being bad, but I poked around the car, smelled gas by the right rear wheel, and opened the access panel in the trunk. After I cleaned up all the dirt I found this:


This is one of the worst I've seen. Could this be causing an EVAP vacuum leak, leading to my O2 problem? Is there anything supposed to be connected to that middle nipple? It smelled like gas pretty strong when I popped the panel off. My Aeroforce has been indicating to me for some time as well that my fuel trims swing wildly between +16.4 and -12.5 when the car is cold, and aren't much better when the car is warm.

Thank you for reading and in advance for your help!

As for the P1133. These are the conditions to set the DTC

Conditions for Setting the DTC
•No injector circuit, MAF sensor, TP sensor, EVAP system, IAT sensor, MAP sensor, Fuel trim , EGR , ECT sensor, or H02S sensor 1 heater circuit DTCs set.
•The engine is running in closed loop.
•Engine speed is between 1000 and 3000 rpm.
•Mass Air Flow is between 10 and 30 gm/s.
•The above conditions are present for a 100 second monitoring period.
•The PCM monitors fewer than 40 rich to lean and 40 lean to rich switches for HO2S 1.

From my experience, 99% of the time, a "Insufficient Switching" O2 code means that the O2 is bad, unless there is something causing it to set the code (refer to above). A leaky fuel tank won't set an O2 code. A leaking exhaust system will though.

As for the P1811....it could literally be anything inside the transmission, including a clogged filter or debris in the VB pressure circuit. The list is like 2 pages long. If the trans continues to shift more then .65 seconds between shifts, it will set the P1811. A failing or bad TPS sensor can cause this code as well, but you'd more than likely have TPS codes for that.

As for your Fuel Tank, I'm surprised it hasn't set an EVAP code yet. There really isn't any adverse driveability effects from it. The Pump is still going to pump fuel regardless of pressure inside the tank.

Thank you Scott. I didn't think to check my exhaust. I have a PLOG, new crossover, and new downpipe as of last year. No audible exhaust leak sounds, but I can check no problem. I suppose it's not out of the question that the O2 sensor may be bad. Looks like I'm doing some more investigating this weekend! For now it's sitting in the garage with the battery disconnected overnight to attempt to try and reset fuel trims/the PCM.

Once I saw how rusty the lock ring was on the tank, I was surprised I didn't see that kind of code either.

I'll scan my TPS, though I don't think that's an issue. I've had a couple bad TPS's on a few cars and this isn't acting like that at all.

I'm not TOO concerned about the transmission. It usually shifts great when the car is cold but after driving for 15 minutes or so it starts to shift just a hair softer, and pretty long in high-RPM shifts. It's always done that. I wanted to put a shift kit in anyway, so that's going in. My fluid has always been clean and red, and I've changed it twice since I've owned it (12,000 miles). Never any debris in the pan whatsoever.

No problem. I was more or less using the TPS as an example. If you've ever seen the trans pressure table (which you will once you start using your tuner), it literally relies on throttle position as a reference for line pressure. So, a skewed TPS would absolutely affect the cars shifting.

Let me know what you find.

That would explain why I couldn't drive my 2000 SSEi very well whenever that TPS started dying .

I'll get back to you this weekend. I hope to do some proding and poking Saturday and Sunday.

Well I reset my PCM via battery disconnection, and the car started good like always and the fuel trim was at 0.0, and after about 2 minutes it slowly climbed up to 16.4 again. I checked the O2 mv and they were a little wild, and then stuck at 445mv for a while, thrn would jump around for a while and go back to 445mv for a while again.

I'm not terribly familiar with cold-start O2 operation, but that doesn't seem real normal. I didnt check to see if it was in open or closed loop at the time. I'm still guessing bad O2 sensor even though it's newish. No noticeable exhaust leaks or vacuum leaks.

The control O2 will jump around wildly and continuously ALL the time. It moves so fast that even a TechII doesn't refresh fast enough to see it. The only time you'll ever get a "constant" reading out of it is at WOT. Normal idle operation is ~98mV-950mV fluctuating. If it's getting "stuck", there's something wrong.

You can't read O2 mv and have it tell you anything meaningful with the rare exception of WOT. It's supposed to jump around. That's actually what the "switching" is that's referred to by the P1133. Switching means the O2 volts went above and then below a certain voltage, which is what happens when each exhaust pulse goes by. It happens with such speed that you can't read it on a digital readout. The PCM has special coding to make useful sense of it. Insufficient Switching is one of the few O2 sensor codes that actually points to the O2 sensor as being the problem, also referred to as a "lazy O2 sensor". FWIW I will only use OEM O2 sensors as replacements.

Thank you for clearing that up, guys. I knew it bounced around quite a bit I just wasn't sure about cold start operation. Either way, i discovered something!

My O2 sensor was loose. WAY loose. Like it wasn't tightened down when it was replaced, at all. It was 2 full turns loose and just wobbling around in the bung. I'm surprised it didn't burn one of the spark plug wires or something. Oh well, all fixed now. I'm not going to replace my sensor just yet, in case nothing is actually wrong with it, and it was just the MASSIVE exhaust leak lol. The fuel trims are looking better already. I'm sure in a few days they'll be lovely.

I also got my shift kit installed today. The shift times aren't as short as I'd like (I installed a mild kit) but they're very consistent, which is more than I could say before. I'll watch that for a while then tune the trans line pressures when I get a few days to just sit and play with the tuning software.

Ah HA! Glad you found it, that wasn't so bad then! I'm surprised you couldn't hear it.

Keep in mind that shift TIMES are also PCM controlled. So even though a "shift kit" has larger hydraulic passages allowing shift pressure to apply quicker, the pressure control solenoid is also in play - the PCM watches historical shift times and adjusts the pressure from the solenoid to match. So if you haven't reprogrammed your shift times, you aren't going to see consistent faster/harder shifts from the shift kit alone.