CEL - P0170 & P0171
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Joined: Jan 2003
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From: D.P. IL
CEL - P0170 & P0171
Hi,
I have a stock MY02 (have it since 03) and it stays stock. I follow the maintenance religiously and never have any problem with it. The problem started late last year when one day I took it out for a short drive (just to keep the battery charged). When I took it back to my garage (engine was already warm after 30 min of driving) the engine stalled when I backed it in my spot. I thought I goofed and let the clutch go a little too fast so I started it up and then I realized the CEL was on. Called my mechanic friend over and he cleared the code for me and hypothesized that the engine computer might have a problem coping with sudden / drastic throttle change and got upset; so it threw me a CEL. So I thought no big deal and the problem didn't reappear the whole winter. BTW, the code was P0171 (system running too lean)
This time it started about 3 weeks ago. I was out driving on the first hot & humid day in Chicago. Running for a few hours and nothing happened. Then I parked it and went for ice cream with my lady friend. Came back; started the car and tried to back it out of a spot. Then the engine stalled! I thought it was weird; started it again and the CEL came on. Then the engine stalled for a few more times (like 3) before I could take it to the next block!? Long story short; I managed to drive it home (stayed below the VTEC the whole time) and called my mechanic friend. He showed up the next day and found out it was the same code (P0170: fuel system, P0171: system running too lean) before he cleared it. We checked the car and he found out there were two hoses that seemed to have slipped off a little (didn't come off of the connection though). He pushed up the hose and zip-tied them. He also zip-tied the map sensor as well. A few days later I drove it out for on and off about 2 hours (on a warm sunny day). Then I went to get groceries and the CEL came on again when I backed the car out of the spot on my way home! Took it to the local Autozone and verified that the code was P0171: system running too lean....
Since then just about every time I start it; it runs fine in the beginning until the rpm settles and it stays at about 500rpm then a jab in the throttle would send the engine speed up a few ticks and then the engine shudders when it comes back down. It'd hover around 500 or 600 rpm and shudders a bit more. Then I blip the throttle again and it would go up and down and struggle to stay at idle speed and finally the engine would go up (when I blip the throttle again) just a little higher and then drop before it'd stall!!
I don't know what is wrong with the car and don't want to take the chance on driving it out and have it stall on me when I don't want it to... I thought about taking it to the stealer but I don't if they can diagnose the problem. I did a little search and found out from MSN Auto that the 02 could have problems with the Evaporative (EVAP) Bypass Solenoid and cause the CEL to come on. But I don't know how to tell if it is indeed the EVAP solenoid that keeps throwing me the CEL...
Can anyone help, please? Any suggestions would be greatly appreciated!!
K
BTW, here's the MSN Auto link:
2002 Honda S2000 Reliability
I have a stock MY02 (have it since 03) and it stays stock. I follow the maintenance religiously and never have any problem with it. The problem started late last year when one day I took it out for a short drive (just to keep the battery charged). When I took it back to my garage (engine was already warm after 30 min of driving) the engine stalled when I backed it in my spot. I thought I goofed and let the clutch go a little too fast so I started it up and then I realized the CEL was on. Called my mechanic friend over and he cleared the code for me and hypothesized that the engine computer might have a problem coping with sudden / drastic throttle change and got upset; so it threw me a CEL. So I thought no big deal and the problem didn't reappear the whole winter. BTW, the code was P0171 (system running too lean)
This time it started about 3 weeks ago. I was out driving on the first hot & humid day in Chicago. Running for a few hours and nothing happened. Then I parked it and went for ice cream with my lady friend. Came back; started the car and tried to back it out of a spot. Then the engine stalled! I thought it was weird; started it again and the CEL came on. Then the engine stalled for a few more times (like 3) before I could take it to the next block!? Long story short; I managed to drive it home (stayed below the VTEC the whole time) and called my mechanic friend. He showed up the next day and found out it was the same code (P0170: fuel system, P0171: system running too lean) before he cleared it. We checked the car and he found out there were two hoses that seemed to have slipped off a little (didn't come off of the connection though). He pushed up the hose and zip-tied them. He also zip-tied the map sensor as well. A few days later I drove it out for on and off about 2 hours (on a warm sunny day). Then I went to get groceries and the CEL came on again when I backed the car out of the spot on my way home! Took it to the local Autozone and verified that the code was P0171: system running too lean....
Since then just about every time I start it; it runs fine in the beginning until the rpm settles and it stays at about 500rpm then a jab in the throttle would send the engine speed up a few ticks and then the engine shudders when it comes back down. It'd hover around 500 or 600 rpm and shudders a bit more. Then I blip the throttle again and it would go up and down and struggle to stay at idle speed and finally the engine would go up (when I blip the throttle again) just a little higher and then drop before it'd stall!!
I don't know what is wrong with the car and don't want to take the chance on driving it out and have it stall on me when I don't want it to... I thought about taking it to the stealer but I don't if they can diagnose the problem. I did a little search and found out from MSN Auto that the 02 could have problems with the Evaporative (EVAP) Bypass Solenoid and cause the CEL to come on. But I don't know how to tell if it is indeed the EVAP solenoid that keeps throwing me the CEL...
Can anyone help, please? Any suggestions would be greatly appreciated!!
K
BTW, here's the MSN Auto link:
2002 Honda S2000 Reliability
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Joined: Jul 2002
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From: Long Island, New York
Bad evap bypass valve will set a P1457, that is not your problem. and its not just the 02 that can have that issue, its 2000-2009.
Your engine has additional air getting into the engine, through a small leak. It sends the fuel trim up and sets a P0171.
Where do you live? Anytime you wanna stop by i can likely fix it.
BTW, your friend is no mechanic
He's just like every other who has no idea, clears the light and makes an off the wall guess.
Your engine has additional air getting into the engine, through a small leak. It sends the fuel trim up and sets a P0171.
Where do you live? Anytime you wanna stop by i can likely fix it.
BTW, your friend is no mechanic
He's just like every other who has no idea, clears the light and makes an off the wall guess.
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Update: valve adjustment Was performed. All valves were loose. Engine had 75k miles. It has been over two weeks and over 150 miles and the owner reports that the engine is running stronger then ever and as smooth as he can remember. No signs of original complaint to date.
Joined: Dec 2009
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From: VA
^^^Hey Billman,
I get the same thing but only about 3 times a year. It doesnt sound as bad as this guys. I just get those 2 codes and some bogging at idle. It seems to only happen after about a 200 mile trip (mostly summer time). I daily the car and it has a CTSC (5psi), MY01. The car gives me no problems, and typically it clears itself or I swing by Autozone and it is always those 2 codes. Thanks.
Not trying to steal thread.
I get the same thing but only about 3 times a year. It doesnt sound as bad as this guys. I just get those 2 codes and some bogging at idle. It seems to only happen after about a 200 mile trip (mostly summer time). I daily the car and it has a CTSC (5psi), MY01. The car gives me no problems, and typically it clears itself or I swing by Autozone and it is always those 2 codes. Thanks.
Not trying to steal thread.
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Joined: Nov 2013
Posts: 4
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Bad evap bypass valve will set a P1457, that is not your problem. and its not just the 02 that can have that issue, its 2000-2009.
Your engine has additional air getting into the engine, through a small leak. It sends the fuel trim up and sets a P0171.
Where do you live? Anytime you wanna stop by i can likely fix it.
BTW, your friend is no mechanic He's just like every other who has no idea, clears the light and makes an off the wall guess.
Your engine has additional air getting into the engine, through a small leak. It sends the fuel trim up and sets a P0171.
Where do you live? Anytime you wanna stop by i can likely fix it.
BTW, your friend is no mechanic
He's just like every other who has no idea, clears the light and makes an off the wall guess.hello Billman,
on this thread I have the same issue as klui_188... with the P0171. I see you offered your help to resolve this issue. unfortunately I live in California and I wish I was closer to you I would swing by. I've read everywhere on how to fix this im lost. this post is the only post I've seen where somebody actually states they can rid the lean code!
Billman if you get a chance to read this please please HELP ME!
the first time the code appeared was when I let the wife drive it and she did light em up a bit not a crazy burnout or whatever, but that was an accident. Second time the CEL P0171 came up was the same. how I cleared it was a buddy of mine used an obd2 reader to clear it but never fixed or told me how to fix it...
can you tell me or show me how to fix this please. I would be forever grateful for your help!
I just recently bought this 2005 SK2 with 49,000 miles. it is FI with greddys turbo kit. running a emanage ultimate, aem failsafe wideband af/boost gauge, rc 550cc fuel injectors and possibly, maybe a fuel pump. not sure dealer did not specify all upgraded components.
Even without all these upgrades listed. what is the fix or diagnoses you would have suggested to klui_188 can you solve my issue?!
I've gone as far as too changing to a 4bar Map sensor but was told I would have to re-tune... so I have NOT added that map sensor. can my oem map sensor handle all this boost pressure?
may this be why its tripping the p0171? do I just need to tune and adjust fuel into the cylinder that's running lean through my emanage?
now mind you my P0171 is not as bad as klui_188. though when it comes on idle staggers abit but hasn't stalled or lost any power... I hope all this info helps to diagnose my problem. I love this car and would like to get it tip top to drive with my lady around town... :-)
Billman please help me. :-(
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Hook up a vacuum gauge to the car, I would start there(any vacuum leak letting un-metered air into the engine will cause a lean condition). Do the simple stuff first, unfortunately hooking up a fuel pressure gauge to the fuel rail is not easy. You either need the special widget from Honda, or you need to tap the fuel rail. Which sucks because seeing fuel pressure would probably point in the direction of your problem. It's harder to find something clogged than it is to find something leaking as well.
