07 A4 3.2L P0172 rich code

Dutchie · Sep 2, 2016

How is the timing of the engine, valve clearance. These can cause mixture errors

Captkrunch · Sep 2, 2016

Dutchie said:
How is the timing of the engine, valve clearance. These can cause mixture errors

Thanks for replying Dutchie! Can these settings be checked with VCDS? I've gone thru all codes in VCDS and didn't find these. Thanks!

Dutchie · Sep 2, 2016

Timing is normaly done with special tools. A experiance diagnostic tec can do a quik check with a scope on the crank and camshaft sensors.

Valve clearance is done with gauches. They dont cost a lot, it's on a v6 a lot of work. If hydraulic are installed they can have some leak and thus not opening the valve all the way.

Captkrunch · Sep 2, 2016

Dutchie said:
Timing is normaly done with special tools. A experiance diagnostic tec can do a quik check with a scope on the crank and camshaft sensors.

Valve clearance is done with gauches. They dont cost a lot, it's on a v6 a lot of work. If hydraulic are installed they can have some leak and thus not opening the valve all the way.

Thanks Dutchie! I`ll have to mention that to the garage i`m going then.

Captkrunch · Sep 3, 2016

So I did a throttle body cleaning and re-learn the throttle body adaptation. Did nothing. I'm still seeing -22% in the bank 1 sensor 1 (this means it's running super rich)

I was told maybe to look at the injectors voltage and see if there was a problem in the wiring. No way to do this while the car is on, the intake manifold is hiding all injectors!

Dutchie · Sep 4, 2016

You can measure on the ECM side

. A LED-tester Midlock is a tool to use. I use the TE-60, the injectors are either positive or negative controlled. The LED shut blink fast between power an ground, compare to get a idea if its ok. When in doubt use a scoop;

Captkrunch · Sep 4, 2016

Hi Dutchie

When you say measure from the ECM side, how would one do that? I have that tool you mentionned but I'm not sure how to use it on the ECM side?

Dank je!

Dutchie · Sep 5, 2016

Take the connectorshield from the ECM connector, and place a backprope on the correct terminals

Captkrunch · Sep 8, 2016

Dutchie, I took the car to Audi dealership.

Result of the diagnostic? They changed the spark plug from cylinder number one to cylinder number two. They notice a bit of carbon buildup on cylinder one. ALl injectors we're tested and non of them are leaking.

They reseted the light and hasn't come back since, nothing in the internal computer as well to report it.

the car is still running rich sitting at idle. So, that's it? The makers of the car can't figure it out too?!

MartinsX · Sep 8, 2016

Captkrunch said:
Dutchie, I took the car to Audi dealership.

Result of the diagnostic? They changed the spark plug from cylinder number one to cylinder number two. They notice a bit of carbon buildup on cylinder one. ALl injectors we're tested and non of them are leaking.

They reseted the light and hasn't come back since, nothing in the internal computer as well to report it.

the car is still running rich sitting at idle. So, that's it? The makers of the car can't figure it out too?!

Sorry, i haven't read all Your thread yet, so I can't comment technical aspects right now, my comments will come later.
Just comment according dealership - dealers do diagnostics and repairs strictly by their workshop manuals, step-by-step fault finding guides and automated fault finding procedures built in dealer level diagnostic equipment. Theoretically any person having basic knowledge of using tools and computer can be a mechanic or electrician at dealers workshop.
I have repaired a lot of cars after unsuccessful repair attempts at dealer's. Just because I use different methods - first of all understanding how things are built, how they must work and then conclusion "WHY it is not working as it have to" comes by itself

Dutchie · Sep 8, 2016

Captkrunch said:
Dutchie, I took the car to Audi dealership.

Result of the diagnostic? They changed the spark plug from cylinder number one to cylinder number two. They notice a bit of carbon buildup on cylinder one. ALl injectors we're tested and non of them are leaking.

They reseted the light and hasn't come back since, nothing in the internal computer as well to report it.

the car is still running rich sitting at idle. So, that's it? The makers of the car can't figure it out too?!

P0172 get set if the HO[sup]2[/sup]S has been for a longer period of time has been registering a O[sup]2[/sup] shortage. The ECM tries to correct this via its fuel trims, the long generally runs to +25%, and then the ECM sets a P0172 fault. So be sure that there is no air restriction. An clogged up intake manifault deu to low RPM and EGR is a possible cause. Also a faulty HO[sup]2[/sup] is a cause.
Please provide a exausttest
Thus
O[sup]2[/sup]
HC
NO[sup]X[/sup]
CO
CO[sup]2[/sup]
Lambda

Both idle and underload, thus not reving the engine wilst the car is in the samespot

Please check the following;

Check ignition system
Engine coolant temp sensor, from a cold engine to hot, cold = 2500 Ohm, hot around 300Ohm
MAP
IAT (intake air temp)
Feulpressure
HO[sup]2[/sup]S, if replaced a OEM one installed?
EVAP, a small leak in this system can drive a tec insane i can tell from experiance

Injecton system

Uwe · Sep 8, 2016

Captkrunch said:
Dutchie, I took the car to Audi dealership.
[...]
So, that's it? The makers of the car can't figure it out too?!

Dealers do not make cars. They only sell them (and parts for them) and ATTEMPT to fix them when they're broken.

-Uwe-

MartinsX · Sep 8, 2016

Please make another one autoscan, after Your visit to dealers garage. Better do it twice - clear all faults, make a testdrive and do a new autoscan. Just to exclude faults stored while testing at dealers.

Dutchie · Sep 10, 2016

Just pops in mind, how many times does the ho2s switches from lean to rich per second?

Jack@European_Parts · Sep 10, 2016

Have you tried crimping off the LDP and N80 circuit.......... to see if the fat mixture vacates?

This is additive ..........so a vacuum leak is very likely causing a rich target as a result.

Keep in mind the inverse or control!

The OXS sensors must be genuine ................

Captkrunch · Sep 11, 2016

Hi! So far, the engine light hasn't returned, but that's normal. It'll take a few days for it to come back as you mentionned

I'll try and answer all the questions you had and once again, thanks a lot for providing assistance with this very, VERY frustrating problem.

All coils are new now, all spark plugs are new, both OXS sensors on bank 1 are new, cleaning the throttle body myself and inspecting the intake, i've been black soot in the intake manifold. Some black stuff is stucked inside (like caked in) but no enough to be causing any issues. Timing is good as well.

They we're talking about rocker arms and lifters? Seems straight foward to install them and it's very cheap.

Thanks!

Captkrunch · Sep 11, 2016

Jack@European_Parts said:
Have you tried crimping off the LDP and N80 circuit.......... to see if the fat mixture vacates?

This is additive ..........so a vacuum leak is very likely causing a rich target as a result.

Keep in mind the inverse or control!

The OXS sensors must be genuine ................

My indy mechanic did that already, no change in the mixture unfortunetely. Good call

Jack@European_Parts · Sep 11, 2016

Well Carbon soaks fuel like a sponge in an intake if caked...........and this creates a lean bund hence a rich additive mixture.

Time for the garbage bag test and watch how it inhales.

Spray intake with fault finer Dye externally than let dry and engine run.

Take intake apart and follow the UV glow..........

What about booster lines for vacuum leak/false air?

Dutchie · Sep 12, 2016

Jack, how does the garbage bag test work?

Jack@European_Parts · Sep 12, 2016

Easy ..........

You wash and dry engine area, and grab a bag + duct tape.

A biosphere of sorts for the engine.

You wrap the bag over top of engine and intake........... building a seal with the tape.

Then watch the bag get sucked in "engine running" to see leak or indicating you must disassemble.

Sometimes I wrap with commercial heavy duty sandwich wrap or packing wrap works well.

You can also take a piece of wrap and tape to a screwdriver while moving over intake areas to see if the wrap gets sucked in or stuck indicating a visual leak.

The dye.......... or a water bottle/garden hose to create misfire or intake spray are also sometimes helpful.

Concentrated smoke in a can used for theatrics works to....... for a good visual when sprayed with carb whip attached.

Not endorsed seller just example.......
http://www.ebay.com/itm/Haze-in-a-c...398753?hash=item3f4c524161:g:e5wAAOSwv0tU7-WA

07 A4 3.2L P0172 rich code

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