Code 172

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Aug 18, 2003 | 05:07 PM

markus

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Code 172

I have a 95 F150 5.0 4x4 with about 130,000 miles. Over the past month or so I have been sporadically get a Check Engine light to come on when I'm on the highway usually after driving over a large hill or accelerating to pass but not limited to those situations. Also my truck doesn't appear to run any differently when the light is on.

I pulled codes KOEO passed (111) as did KOER (111) but I have 172 in memory and that's the only code in memory. I started basic. I looked over the exhaust manifolds and y pipe for cracks and I didn't see any. I also looked over all the vacuum tubes and didn't see any leaks there either. I've been using the clean your fuel injectors additive for the past tankful of gas with no results as well. My next step is to check/replace the fuel filter. Is there a way I can test the O2 sensor? What else should I try? My truck is a little on the sluggish side could I need my injectors cleaned or replaced? Thanks.

Aug 19, 2003 | 07:28 AM

fishin1976

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Code 172

Anybody know what a code 172 is? I don't have my book in front of me.

Aug 19, 2003 | 07:37 AM

djd67

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Code 172

172 in my book says hego or ho2s oxegen sensor

Aug 19, 2003 | 07:40 AM

djd67

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Code 172

for more info refer to your haynes man. 4-22(15)

Aug 19, 2003 | 08:09 AM

markus

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Code 172

Oh yeah I forgot Code 172 is O2 Sensor reporting a lean condition.

Aug 24, 2003 | 06:25 AM

markus

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Code 172

I changed the fuel filter yesterday and I still get the Check Engine light to come on while on the highway

. Should I have reset my computer during the filter change? BTW the filter was noticablely harder to blow through than the new one but none of the gas that poured out of it was discolored or murky

. What should my next step be? Professional Injector Cleaning? I'm still looking for an 02 Sensor test.

Aug 24, 2003 | 06:04 PM

steve83

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From: Memphis, TN

Code 172

The Haynes manual tells how to test the HEGO with a multimeter, but check your engine bay for a vacuum leak. Then test the fuel pressure with a gauge on the fuel rail.