OT: Need help with Taurus codes

Hi guys,

The 1998 Taurus is throwing codes P0171 and P0174, and I need help troubleshooting. Anyone know a good source of info for the Taurus?

Arlie

Reply to
Blue Gator
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Here ya go Gator :)

Kate

Diagnostic Trouble Codes (DTCs) P0171 bank 1 (Cylinder 1) and DTC P0174 bank

2 indicate the fuel/air ratio is too lean. The fuel trim system is at the rich correction limit.

DTC P0172 bank 1 and DTC P0175 bank 2 indicate the fuel/air ratio is too rich. The fuel trim system is at the lean correction limit.

HO2S DTCs Reference list:

-- HO2S-11 = DTCs P0171 and P0172

-- HO2S-21 = DTCs P0174 and P0175

Possible causes:

Fuel system

-- Excessive fuel pressure.

-- Leaking fuel injector(s).

-- High fuel pressure.

-- Low fuel pressure.

-- Contaminated fuel injector(s)

Ignition system

-- Spark plugs.

-- Spark plug wires.

-- Coils.

Induction system

-- Air leaks after the MAF sensor assembly.

-- Vacuum leaks.

-- Restricted air inlet.

-- PCV system.

-- Improperly seated engine oil dipstick.

Base engine

-- Oil overfill.

-- Cam timing.

-- Cylinder compression.

-- Exhaust leaks before or near the HO2S(s).

l Check intake air system for leaks, obstructions and damage. l Check air cleaner element, air cleaner housing for blockage. l Verify fuel level. l Verify integrity of the PCV system. l Check for disconnected spark plug wires. l Check for vacuum leaks.

l Verify customer did not run out of fuel.

l Are any of the above concerns present?

Yes REPAIR as necessary. RERUN «Quick Test».

No GO to Pinpoint Test Step «DC25». If MAF reading is within specification, return to Pinpoint Test Step «HA42».

Reply to
Kate

Wow, that was fast. Now I have to wade through all that! At least I know where to start. Thanks, Kate.

Arlie

Reply to
Blue Gator

"Blue Gator" wrote : Wow, that was fast. Now I have to wade through all that! At least I : know where to start. Thanks, Kate. : : Arlie

You're welcome :)

Hope you find the problem.

My guess is, check the PCV valve first if you haven't changed it in awhile, reset the computin machine and try again.

Kate

Reply to
Kate

Clean the MAF

Reply to
Backyard Mechanic

Just thought I'd give you an update. Once I figured out where the PCV valve is on the *danged* Taurus, the problem turned out to be a hole in the hose from the valve to the intake manifold. The area around the hole was soft, sticky and spongy. Don't know what caused that, but a new hose fixed the problem. Put a new PCV valve in while I was at it.

Thanks for your help, Kate. You won first prize!

Arlie

Reply to
Blue Gator

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