Codes p0172, p0175, p223, p2240, p0136, and p0156?

Hi,

By chance, do you have a live data scan tool? If you do, connect it and allow the engine to reach operating temperature. Check the short-term fuel trims and record them. Next, check the oxygen sensors to see if there are changing back and forth in voltage. The voltage should be between 0 and 1.0v. Let me know how they respond when you press the throttle.

Last, the idea that you have a rich fuel mixture on both banks could simply be the result of a faulty fuel pressure regulator. Has that been checked? If not, here is a link that explains how to check fuel pressure. You will need a gauge, but most parts stores will lend one to you.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

I attached the manufacturer's fuel pressure specifications below for you.

Let me know what you find.

Take care,

joe

See pic below.

First, let me thank you for addressing this for me. This site is something that helps a lot of people.

I have an OBD II and OBD eleven for the audi/vw group but do not think they will scan like you have mentioned for fuel trims. Next, awhile a go, i put some fuel injector cleaner in the car and the little paper crap on top that you puncture to open it fell into the tank. Could that get stuck next to the fuel pickup and cause the pressure regulator issue you speak off.

I will try and check the stuff you have mentioned in the meantime.

odd thing is most of the time the car runs just fine and normal.

Again, Thanks.

Hi,

First, you are very welcome. I just hope I can help. It is a lot more difficult diagnosing when the vehicle isn't in front of me. LOL

As far as your concerns with the injector cleaner cap, it could be stuck at the pump, but I don't think this would be the result, but anything is possible.

If that is the case, it will restrict fuel flow and we will see that in the fuel trims.

Let me know if you are able to get that information.

Take care,

Joe

Sorry, it has taken me awhile. I just got the Ross VCDS. i have the following:
O2 sensors
Bank 1 Sensor 1 80 ohm
b1 s2 834 ohm
b2 s1 80 ohm
b2 s2 720 ohm

S1 voltages up to 1.9v
s2 voltages about 0.8v

long term fuel trim is B1 -7.8%
B2 -4.78%

Short term Fuel trim B1 -7%
b2 -7%

Idle 700 rpm

fuel pressure 4750 Kpa

I also have O2 sensor voltage going from about 0.7 down to about 0 with a associated parameter of 99.2%.

car is running fine but the codes show the original O2 issues are intermittent.

Here is a typical fault code reading
engine spd 1237
engine spd actual 1024
normed load value 0%
vehickle speed 46 KMh
coolant temp 91
intake air temp 35
ambiant air pressue 990 mbar
voltage 30 termianl 14.116
MAF_ENVD: 65.36470 mg/stroke
engine operating status: PUC
engien load: 0%
STATE_LS_ENVD(1): 4 (OR DOES SAY 8 OR 2)

Thanks for your help!

Hi,

The ECT and the IAT are odd. Was the vehicle cold when you got the readings? Also, is the temperature Fahrenheit or Celsius? What was the ambient temperature?

As far as the items you listed, nothing seems really out other than the temperatures.

Let me know.

Joe

Temperatures in Celsius (because that is how it reads, argh). Ambient about 100 Fahrenheit. readings taken when warmed up. and yes, the car is running fine. That typical fault code i sent is what sets of the service engine soon light and gives me the bad o2 sensor faults. It clears up, as far as running, usually within minutes but the service light stays on for a while until i delete it or i assume go through enough duty cycles to clear it. I cannot figure out what might be making it go off like that intermittently. I am going to check for vacuum leaks with a can of staring fluid stuff and see if that might be it as i saw a note that, believe it or not, they took out the trans dipstick and it made the fuel trims run negative, put it back in and then all fine. so, it is very sensitive to other crap. I assume fuel trims within +/- 6-7 mis acceptable. I appreciate your thoughts and help. What do you mean by the ECT and IAT are at odds?

Hi,

I wasn't sure about the temperatures (Fahrenheit or Celsius) and what I was reading didn't make sense to me. LOL

If I understand correctly, when the transmission dipstick is removed, the computer tries to lean the fuel mixture. I'm trying to make sense of that.

Also, when you check for vacuum leaks, you may want to use carb cleaner. Starting fluid, if it hits the wrong spot, can ignite.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Let me know what you find.

Joe

Look at around 2:08 in video to see what i was saying about the dipstick. i saw this video, i did not do this with my engine.

https://www.youtube.com/watch?v=yM3iarhSP68

and yes, carb cleaner or other will be used not actual starting fluid. Thanks for the vacuum leak check link.

Hi,

Thanks for the update. Also, I did watch the video and now it makes sense to me. LOL I wasn't thinking of a vacuum leak being created when it is removed. Ugh! I'm getting old. LOL

Let me know how things turn out for you.

Joe

Just wanted to reply that for the last 2 months the error codes have not gone off and i did not change anything on the car. It appears that when the ambient temperature is at 93 or hotter, then that is when the car gets finicky, and the codes will get thrown. Below that Temperature and all is fine. Hmm, odd. I am thinking that maybe the ambient air temperature sensor is going bad and flips out it the hot temperatures here in Texas.

Hi,

Thanks for the update. I went through our replies. You provided an ECT (coolant temp) when at operating temperature. Have you ever checked the ECT temp signal when it is colder outside, and you would likely have the problem before the engine is started and warm?

Let me know.

Joe