need some help on likely vacuum leak

[piss&vinegar]

About a month or so ago I had a thermostat stick closed on me. I was not far from the house when this happened and when I began to pull away at the first stop light I encountered I got the bucking action which told me that the car is getting hot. Replaced thermostat and all was good for about 2 weeks then I started getting a p0171 and p0174 code. This was for lean condition on both banks. I did a smoke test and found nothing. I check for exhaust leak on bolts are good and tight. I cleaned the MAF, replaced fuel filter and made sure everything was snug on the intake and on next crank got P2195 and p2197. I then reset the computer just in case as these are codes for stuck conditions. I connected my data logger up and am noticing short term fuel trim high(25% and 32%) on both banks at idle. Now, the car has a canned tuned and it has been working fine for about 2 years. I am not sure where to look next or what to do. I do have 2 questions - if I am looking at a data logger and watching the fuel trim, is the percentage of change(+/-) directly altered by the tune or is the O2 showing the result of what the tune is actually doing? I hope that made sense. Next, does the Eaton have elbow at the back that I believe connects to the PCV that can go bad and need to be replaced. I don't want to take the blower off just to find nothing is there.

Thanks,
Dave

 

[hotcobra03]

About a month or so ago I had a thermostat stick closed on me. I was not far from the house when this happened and when I began to pull away at the first stop light I encountered I got the bucking action which told me that the car is getting hot. Replaced thermostat and all was good for about 2 weeks then I started getting a p0171 and p0174 code. This was for lean condition on both banks. I did a smoke test and found nothing. I check for exhaust leak on bolts are good and tight. I cleaned the MAF, replaced fuel filter and made sure everything was snug on the intake and on next crank got P2195 and p2197. I then reset the computer just in case as these are codes for stuck conditions. I connected my data logger up and am noticing short term fuel trim high(25% and 32%) on both banks at idle. Now, the car has a canned tuned and it has been working fine for about 2 years. I am not sure where to look next or what to do. I do have 2 questions - if I am looking at a data logger and watching the fuel trim, is the percentage of change(+/-) directly altered by the tune or is the O2 showing the result of what the tune is actually doing? I hope that made sense. Next, does the Eaton have elbow at the back that I believe connects to the PCV that can go bad and need to be replaced. I don't want to take the blower off just to find nothing is there.

Thanks,
Dave

if you havent download the manual..

2195/97 are lean codes for lack of switching...

171/174 were for unmettered air...

same o2s just a different function of o2

these are not codes for bad o2s..its what your o2s are reading...

just added,,

there is a hose on a stock cobra on back of supercharger for pcv,,it does T off and goes under supercharger...you will need to pull the supercharger,,,


as a first timer pulling....level of difficulty 1-10 its a 1...

supercharger can be pulled as an assembly and intake gaskets are reuse if not damaged....

going easy it an 1hr job to do this...when knowing what steps are needed..

 

[piss&vinegar]

Thanks hotcobra3! Anything else to check before going that route?

 

[hotcobra03]

Thanks hotcobra3! Anything else to check before going that route?

for wanting to learn you need to first read and understand,,,

the manual is written for someone who has already learned the basics,so it could take awhile to get..

heres small copy/paste from manual...than you will see why ..

P2195 - Lack of HO2S-11 Switch, Sensor Indicates Lean A HEGO sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time.

• 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 oil dipstick
• EGR System:
  • Leaking gasket
  • Stuck EGR valve
  • Leaking diaphragm or EVR
• Base Engine:
  • Oil overfill
  • Cam timing
  • Cylinder compression
  • Exhaust leaks before or near the HO2S(s)

2003 PCED OBDII
SECTION 2: Diagnostic Methods

Adaptive Fuel DTCs Diagnostic Techniques
Adaptive Fuel DTCs Diagnostic Techniques help isolate the root cause of the adaptive fuel concern. Before proceeding, attempt to verify if any driveability concerns are present. These diagnostic aids are meant as a supplement to the pinpoint test steps in Section 5. For a description of fuel trim, refer to Section 1 , Powertrain Control Software, Fuel Trim.
Obtain Freeze Frame Data
Freeze Frame Data can be helpful in duplicating and diagnosing adaptive fuel concerns. This data (a snapshot of certain PID values, recorded at the time the DTC was stored in Continuous Memory) is helpful to determine how the vehicle was being driven when the fault occurred, and can be especially useful on intermittent concerns. Freeze Frame Data, in many cases, can help to isolate possible areas of concern as well as rule out others. Refer to Freeze Frame Data in this section for a more detailed description of this data.
Using the LONGFT1 and LONGFT2 (dual bank engines) PIDs
The LONGFT1/2 PIDs can be useful for diagnosing fuel trim concerns. A negative PID value indicates that fuel is being reduced to compensate for a rich condition, while a positive PID value indicates that fuel is being increased to compensate for a lean condition. It is important to know that there is a separate LONGFT value that is used for each rpm/load point of engine operation. When viewing the LONGFT1/2 PIDs, the values may change a great deal as the engine is operated at different rpm and load points. This is because the fuel system may have learned corrections for fuel delivery concerns that can change as a function of engine rpm and load. The LONGFT1/2 PIDs will display the fuel trim currently being used at that rpm and load point. Observing these changes in LONGFT1/2 can help when diagnosing fuel system concerns. For example:

• A contaminated MAF sensor would result in matching LONGFT1/2 correction values that are negative at idle (reducing fuel), but positive (adding fuel) at higher rpm and loads.
• LONGFT1 values that differ greatly from LONGFT2 values would rule out concerns that are common for both banks (for example, fuel pressure concerns, MAF sensor, etc. could be ruled out).
• Vacuum leaks would result in large rich corrections (positive LONGFT1/2 value) at idle, but little or no correction at higher rpm and loads.
• A plugged fuel filter will result in no correction at idle, but large rich corrections (positive LONGFT1/2 value) at high rpm and load.

Resetting Long Term Fuel Trims
Long term fuel trim corrections can be reset by resetting the PCM Keep Alive Memory (KAM). Refer to Resetting Keep Alive Memory in this section to reset KAM. After making a fuel system repair, KAM must be reset. For example, if dirty/plugged injectors cause the engine to run lean and generate rich long term corrections, replacing the injectors and not resetting KAM will now make the engine run very rich. The rich correction will eventually be "learned out" during closed loop operation, but the vehicle may have poor driveability and have high CO emissions while it is learning.
P0171/P0174 System Too Lean Diagnostic Aids
Note: If the system is lean at certain conditions, then the LONGFT PID would be a positive value at those conditions, indicating that increased fuel is needed.
The ability to identify the type of lean condition causing the concern can be crucial to a correct diagnosis.
Air Measurement System:
With this condition, the engine may actually run rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the Powertrain Control Module (PCM) is not able to compensate enough to correct for the condition. One possibility is that the mass of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM. For example, with a contaminated MAF sensor, the engine would run lean at higher rpm because the PCM would deliver fuel for less air than is actually entering the engine.
Examples: MAF sensor measurement inaccurate (corroded connector, contamination/dirty (a contaminated MAF sensor will typically result in a rich system at low airflows (PCM will reduce fuel) and a lean system at high airflows (PCM will increase fuel), etc).
Vacuum Leaks/Unmetered Air:
With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the Powertrain Control Module (PCM) is not able to compensate enough to correct for the condition. This condition can be caused by unmetered air entering the engine, or due to a MAF malfunction. In this situation, the volume of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM. Vacuum leaks will normally be most apparent when high manifold vacuum is present (for example, during idle or light throttle). If freeze frame data indicates that the fault occurred at idle, a check for vacuum leaks/unmetered air might be the best starting point.
Examples: Loose, leaking or disconnected vacuum lines, intake manifold gaskets or o-rings, throttle body gaskets, brake booster, air inlet tube, stuck/frozen/aftermarket PCV valve, unseated engine oil dipstick, etc.
Insufficient Fueling:
With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This condition can be caused by a fuel delivery system concern that restricts or limits the amount of fuel being delivered to the engine. This condition will normally be most apparent when the engine is under a heavy load and at high rpm, when a higher volume of fuel is required. If freeze frame data indicates that the fault occurred under a heavy load and at higher rpm, a check of the fuel delivery system (checking fuel pressure with engine under a load) might be the best starting point.
Examples: low fuel pressure (fuel pump, fuel filter, fuel leaks, restricted fuel supply lines), fuel injector concerns, etc.
Exhaust System Leaks:
In this type of condition, the engine may actually be running rich of stoichiometry (14.7:1 air / fuel ratio) because the fuel control system is adding fuel to compensate for a perceived (not actual) lean condition. This condition is caused by oxygen (air) entering the exhaust system from an external source. The HO2S will react to this exhaust leak by increasing fuel delivery. This condition will cause the exhaust gas mixture from the cylinder to be rich.
Examples: Exhaust system leaks upstream or near HO2S, poorly welded/leaking HO2S boss, malfunctioning Secondary Air Injection system, etc.
P0172/P0175 System Too Rich Diagnostic Aids
Note: If the system is rich at certain conditions, then the LONGFT PID would be a negative value at that airflow, indicating that decreased fuel is needed.
System rich concerns are usually caused by fuel system concerns, although the MAF sensor, and base engine (for example, engine oil contaminated with fuel) should also be checked.
Air Measurement System:
With this condition, the engine may actually run rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the Powertrain Control Module (PCM) is not able to compensate enough to correct for the condition. One possibility is that the mass of air entering the engine is actually less than what the MAF sensor is indicating to the PCM. For example, with a contaminated MAF sensor, the engine would run rich at idle because the PCM would deliver fuel for more air than is actually entering the engine.
Examples: MAF sensor measurement inaccurate (corroded connector, contamination/dirty (a contaminated MAF sensor will typically result in a rich system at low airflows (PCM will reduce fuel) and a lean system at high airflows (PCM will increase fuel), etc.).
Fuel System:
With this condition, the engine may actually run rich of stoichiometry (14.7:1 air/fuel ratio) if the Powertrain Control Module (PCM) is not able to compensate enough to correct for the condition. This situation can be caused by a fuel delivery system that is delivering excessive fuel to the engine.
Examples:

• Fuel pressure regulator causes excessive fuel pressure (system rich at all airflows)(fuel pressure can be intermittent, going to pump deadhead pressure, then returning to normal after engine is turned off then restarted).
• Fuel pressure regulator vacuum hose off (causes excessive fuel pressure at idle, system rich at idle airflows).
• Fuel pressure regulator diaphragm ruptured (fuel leaking into intake manifold, system rich at lower airflows).
• Fuel return line crimped/damaged (fuel pressure high, system rich at lower airflows).
• Fuel injector leaks (injector delivers extra fuel).
• EVAP canister purge valve leak (if canister is full of vapors, introduces extra fuel).
• Fuel rail pressure sensor (electronic returnless fuel systems) concern causes sensor to indicate lower pressure than actual. PCM commands higher pressure to the fuel pump driver module (FPDM), causing high fuel pressure (system rich at all airflows).

Base Engine
Engine oil contaminated with fuel can contribute to a rich running engine.

 

[piss&vinegar]

I did detect a small idle change when spraying TB cleaner around the EGR area/PCV line near back of supercharger. I am not against taking the supercharger off I just want to make sure that it is the problem. Is there a way to know for sure? I am going to get more cigar tomorrow to do a smoke test by injecting smoke into the PCV line near the back of the supercharger. This is becoming a major PITA!!

 

[hotcobra03]

there is an elbow on back of supercharger that crumbles...and causes these codes..

it is on the pcv line....the green vaccum hose on egr is known to get melted...

these are so common that yours should have had those issues already...but than again maybe not...

this site will have pics in color from members that will help..

top of each section has stickys..these contain information that is important to us..

you will find a link for the 2003 factory manual ....read and read...

these codes are great for a first timer to learn from...

on my first time i pulled the complete vaccum harnes off and found 3 issues..

i had issues with the line going under intake also..line has harded over time..it didnt pull off the nipple but it would spin on it...thats a leak...had to clamp it

 

[piss&vinegar]

Thanks! I guess I will start removing it tonight. The only thing I find interesting is that one side is 32% while the other will range around 25%. I guess I would think they would both stay close to the same but either way it seems that the supercharger has to come off.

 

[hotcobra03]

Thanks! I guess I will start removing it tonight. The only thing I find interesting is that one side is 32% while the other will range around 25%. I guess I would think they would both stay close to the same but either way it seems that the supercharger has to come off.

take a pic before touching anything..
1 hose in the wrong spot will get you
here is what it all looks like

http://www.accutach.com/Documents/VacuumHarnessSchematicR2.pdf

 

[piss&vinegar]

Thanks for the link!! Will definitely help!

 

[piss&vinegar]

Problem fixed. Was 2 of the 3 PCV hoses. The one from the valve itself and the one that goes to the plenum. Both had cracks in them. Thanks for your help!!

 

[03cobra#694]

^^^Dry rotted and cracked? Glad you got and thanks for posting results.

 

[piss&vinegar]

Yep. Dry rotted and crack. I think the heat and oil did them in. If I had to remove the supercharger to get the line that goes to lower intake it would have been replaced with a mammoth or a whipple.

 

[hotcobra03]

Yep. Dry rotted and crack. I think the heat and oil did them in. If I had to remove the supercharger to get the line that goes to lower intake it would have been replaced with a mammoth or a whipple.

glad you got it..

if you did pull blower for bottom ,you would really be amazed to how fast you can r/r the upper intake...solo:beer:

 

[lucasmelo]

How?

How did you fix it? Did you change the the whole harness?
Running into the same problem.

Appreciate any advice...:??: