CEL P0171 Check Engine Light Code, After Timing Belt Replacement
11-10-2008
#1
Registered!!
Thread Starter
iTrader: (3)
Join Date: Mar 2002
Location: Abingdon, Maryland, US
Age: 44
Posts: 1,389
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 284 
CEL P0171 Check Engine Light Code, After Timing Belt Replacement
2002 Honda Civic HX
130,000 ish miles.
I just had the Stealership do the Timing Belt Replacement, Water Pump, New Drive Belt, New Coolant. And while they were in there I had them Adjust the Valves for $95 extra.
They did this on Saturday 11/8/08 and I wasn't able to pick the car up till this morning 11/10/08 so it Sat for two Days. After picking up the car and driving it to school, the CEL (Check Engine Light) comes on. I went to Advanced Auto Parts and borrowed thier OBD2 reader, and This is what it said
The Manual Reads
P0171 - System too lean (Bank 1)
*Also in Sticky Post for OBD2 codes
The Advance Auto peoples suggested tightening the gas cap and said it was most likely the 02 sensor. I asked which one and they said the one right before the Catylitic Convertor.
After searching the posts, I found this helpful post from rickinthescv
I'm assuming (hoping) rick got this straight from the Honda service manual, can anyone verify that?
My problem is that if I take it to the Stealership and they say it is not related to the work they just did they will charge me $80 just to plug it into the OBD2. And if it's the 02 sensor, then yeah. But rick also mentioned the valve adjustment that I did have done.
QUESTIONS:
1) What exactly does the valve adjustment do? And was it worth the $95
2) Confirm the service manual procedure for P0171
3) Confirm the location of the 02 sensor, if indeed it is related to the code.
4) In step 3, of rick's procedure, do I just measure that with a volt meter? Any details on that? Where to put the prongs?
Thanks guys!
130,000 ish miles.
I just had the Stealership do the Timing Belt Replacement, Water Pump, New Drive Belt, New Coolant. And while they were in there I had them Adjust the Valves for $95 extra.
They did this on Saturday 11/8/08 and I wasn't able to pick the car up till this morning 11/10/08 so it Sat for two Days. After picking up the car and driving it to school, the CEL (Check Engine Light) comes on. I went to Advanced Auto Parts and borrowed thier OBD2 reader, and This is what it said
Originally Posted by OBD2
P0171
Mil On
Monitrs
0 INC
8 READY
Misfire
Fuel Comp
Catylst Evap
02 Snsr
02 Htr
EGR
Mil On
Monitrs
0 INC
8 READY
Misfire
Fuel Comp
Catylst Evap
02 Snsr
02 Htr
EGR
P0171 - System too lean (Bank 1)
*Also in Sticky Post for OBD2 codes
The Advance Auto peoples suggested tightening the gas cap and said it was most likely the 02 sensor. I asked which one and they said the one right before the Catylitic Convertor.
After searching the posts, I found this helpful post from rickinthescv
Originally Posted by rickinthescv
Dtc P0171
If no other trouble codes are listed:
1. Check the fuel pressure.
If the fuel pressure is too high: replace the fuel pressure regulator.
If the fuel pressure is too low: check the fuel pump, the fuel feed pipe, the fuel filter, and replace the fuel pressure regulator.
IF the fuel pressure is okay.
2. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or Neutral) until the radiator fan comes on.
3. Check the primary HO2S (Sensor 1) output with the scan tool.
If it stays at less than 0.3 volts or more than 0.6 volts replace the sensor.
If not:
4. With a vacumm pump, apply vacuum to the evaporative emission canister (EVAP) purge valve.
If it holds vacuum, check the valve clearances and adjust if necessary. If the valve clearances are okay, replace the injectors.
If not, replace the EVAP cannister purge valve.
Fuel pressure should be 40-47 psi. The most likely, cheapest, and easiest thing to fix, would be the fuel filter.
If no other trouble codes are listed:
1. Check the fuel pressure.
If the fuel pressure is too high: replace the fuel pressure regulator.
If the fuel pressure is too low: check the fuel pump, the fuel feed pipe, the fuel filter, and replace the fuel pressure regulator.
IF the fuel pressure is okay.
2. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or Neutral) until the radiator fan comes on.
3. Check the primary HO2S (Sensor 1) output with the scan tool.
If it stays at less than 0.3 volts or more than 0.6 volts replace the sensor.
If not:
4. With a vacumm pump, apply vacuum to the evaporative emission canister (EVAP) purge valve.
If it holds vacuum, check the valve clearances and adjust if necessary. If the valve clearances are okay, replace the injectors.
If not, replace the EVAP cannister purge valve.
Fuel pressure should be 40-47 psi. The most likely, cheapest, and easiest thing to fix, would be the fuel filter.
My problem is that if I take it to the Stealership and they say it is not related to the work they just did they will charge me $80 just to plug it into the OBD2. And if it's the 02 sensor, then yeah. But rick also mentioned the valve adjustment that I did have done.
QUESTIONS:
1) What exactly does the valve adjustment do? And was it worth the $95
2) Confirm the service manual procedure for P0171
3) Confirm the location of the 02 sensor, if indeed it is related to the code.
4) In step 3, of rick's procedure, do I just measure that with a volt meter? Any details on that? Where to put the prongs?
Thanks guys!
11-14-2008
#2
Prowlin' with a Purpose
iTrader: (16)
Join Date: Nov 2002
Location: Minnesota
Age: 41
Posts: 5,239
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 314 Re: CEL P0171 Check Engine Light Code, After Timing Belt Replacement
valves are too tight..
*edit* valve adjustments keep the engine running normally, too tight and it gets lean, too loose and you loose power, over time they get looser due to the carbon buildup between the valves and the valve seat, causing loss in performance and some noise
i had the same thing happen to me when i adjusted my valves, check engine light would come on, then i would clear it, it would drive normally though.. take it back to the dealership and say it wasnt on before you had all this work done
*edit* valve adjustments keep the engine running normally, too tight and it gets lean, too loose and you loose power, over time they get looser due to the carbon buildup between the valves and the valve seat, causing loss in performance and some noise
i had the same thing happen to me when i adjusted my valves, check engine light would come on, then i would clear it, it would drive normally though.. take it back to the dealership and say it wasnt on before you had all this work done
Last edited by WannaBFast; 11-14-2008 at 08:47 AM.
Thread
Thread Starter
Honda Civic Forum
Replies
Last Post
tylerginevan
Hybrid Engine/IMA battery system
10
04-27-2015 12:29 PM
dragonsblood
Mechanical Problems/Vehicle Issues and Fix-it Forum
6
04-27-2015 12:28 PM
dooner24
Mechanical Problems/Vehicle Issues and Fix-it Forum
1
04-14-2015 07:51 PM
