98 S70 GLT Emission Woes, DTCs and Stalling (MAF?)

[ncaapicks]

Virginia has a two year cycle for emissions testing and I've had issues for the last two and am right up against the third cycle. It appears P0171 and P0442 have been consistent issues and have been remedied in the past with an evap hose, check valves and/or purge valves.

In preparation for my current date (now past due) with my friends from the Commonwealth, I was going to try and track down those vacuum leaks. A couple of weeks ago, I ended up limping home after the car began stalling. The engine would die almost immediately after turning over. The next morning I pulled the following codes:
P0108 - MAP Pressure Circuit High Input
P0171 - System Too Lean (Bank 1)
P0243 - Turbocharger Wastegate Solenoid A Malfunction
P0442 - Evaporative Emission Control System Leak Detected (small leak)
P0455 - Evaporative Emission Control System Leak Detected (no purge flow or large leak)
P0505 - IAC (Idle Air Control) System Malfunction
*No code presented for my MAF sensor.

I did some trouble shooting, some pulling and tugging, and some cleaning, and reset my codes.

My research suggested that, along with vacuum leaks, my MAF sensor may be bad. With it connected, the engine will not continue to run without playing with the gas pedal and I have smoke coming from the exhaust and a strong smell of fuel. If I unplug the MAF, the car will idle and run adequately. Running codes again, with my MAF disconnected, I obviously have a P0102-Mass or Volume Air Flow Circuit Low Input and a pending P0171. In my fooling around with the MAF connected, I got a P0243.

This weekend, I replaced a number of vacuum lines. Every line between the front of the engine and the radiator has been replaced. The bottom line from the air intake hose (Air Mass Meter to Turbo) that connects to the turbo control valve has been replaced. The elbows from the white plastic line going from the air intake tube to the fuel pressure regulator? and the purple line from the ARW?? to the solenoid valve behind the radiator (secondary air system?) were in very poor shape and were replaced.
The three or four other elbows I see seem to be in pretty good shape.

I think I have two more not including the brake booster line and the three lines for the turbo control valve left to replace. The infamous manifold (passenger side to PTC) and one that runs from the front of the intake manifold to somewhere near the turbo below the air intake tube. I need some help with this one and will post pictures in a second post.

Other maintenance item on my list are to replace the fuel filter and clean the throttle body and idle air control valve.

Thanks for your patience with my narrative. My questions:

1. Is my MAF bad or should I wait on the resolution of any vacuum issues before ordering a replacement? I'm trying to locate anyone with a compatible 70 or 850 to test. Searching for friends of friends.

2. Since replacing the items mentioned above, I only get the MAF code. No sign of a pending 171 in the 7 or so miles I've driven the car since. If I remember correctly, before the work, the pending 171 popped up pretty quicky. What kind of drive cycles does the system have to go through before triggering codes?

[abscate]

Unplugging the MAF and getting good running is indicative of MAF failure OR a vacuum leak. If unmetered air is getting into your engine it won't run well.

[ncaapicks]

Here are the pictures of the line I was asking about in my previous post. The line is in pretty bad shape and crumbles a bit when I handle it.

This line in question is directly under the line with the clamp. The intake manifold is to the left. The idle air control valve is directly to the right. The line runs under the IAC, along the end of the block, and somewhere down near the turbo.



This photo is of the line between the right end of the engine block and the air intake tube. The line is routed under the larger diameter line and the intake tube. What does it do? and where does it end? I imagine I'm going to have to pull the tube to replace this as well as the TCV lines. Thanks for your help.

Roger

[ncaapicks]

I just wanted to clarify a statement above. I do not get a MAF code unless the thing is disconnected.