Po171 code.. again... reposted from mantenance

bamayote · 06-06-2003, 01:29 PM

well, this all started in feb. here's the original thread. http://www.yotatech.com/showthread....highlight=p0171

synopsis: got the 171 code bank 1, changed the upstream 02 sensor, got a 171 code again bank2, changed the downstream 02 sensor, got 171 code again with both bank one and bank two showing. i had the injectors cleaned by the local mechanic. it wasn't the ultrasonic clean, but the snap on motor vac. i can tell a difference, the motor is more responsive, better pickup and accerlation, HOWEVER, the infectios, small pox ridden 171 code came up again. bank one lean.

what next?...... did i get a bad new sensor? or is there something else i'm missing? i've searched the forum pretty heavily so i hope i'm not asking any questions that have already been answered.
thanx
brad

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Dr. Zhivago · 06-06-2003, 01:37 PM

The link you provided does not work...

So, I'm assuming that no one told you to clean the MAF Sensor. Also, check for vacuum leaks. I don't know what year you have, but I can guess that it is a 3rd Gen.

Cleaning the MAF on a 99-02 is a really simple procedure, and not so much on a 96-98.

Look into having the MAF cleaned or replaced and triple check for vacuum leaks. Even the smallest ones can cause this problem.

Hope this helps.
Dr. Z

bamayote · 06-06-2003, 04:33 PM

i cleaned the maf (which made a big difference in performance).
checked for vac leaks till i'm blue.......lol
and i may just replace the maf this time and see if that works.
i was just looking for any other ideas. i've pretty much been down the list as far as the usual culprits that i've read about on yotatech.
lemme see if i can get another link.......thanx for the reply dr z. you were most helpful when this first came up.

http://www.yotatech.com/showthread.p...ighlight=po171

bamayote · 06-08-2003, 10:55 AM

did the link work this time?

FattyCBR · 06-08-2003, 11:21 AM

Has your throttle body ever been removed? It's possible to put the gasket between the TB and plenum in backwards, which can cause a vacuum leak/problem. I'd say if you still have the code after replacing both O2 sensors than you definitely have a vacuum leak.

bamayote · 06-08-2003, 01:55 PM

never thought i'd ever say.......'thanx fatty".
thanx for the reply....i'll go over it again. and no the throttle body has never been removed. and it idles fine........it idles around 6-700rpm.
cya
brad

06-06-2003, 04:33 PM	#3 (permalink)
bamayote Registered User Join Date: Nov 2002 Posts: 142	yeah dr z i cleaned the maf (which made a big difference in performance). checked for vac leaks till i'm blue.......lol and i may just replace the maf this time and see if that works. i was just looking for any other ideas. i've pretty much been down the list as far as the usual culprits that i've read about on yotatech. lemme see if i can get another link.......thanx for the reply dr z. you were most helpful when this first came up. http://www.yotatech.com/showthread.p...ighlight=po171

06-08-2003, 10:55 AM	#4 (permalink)
bamayote Registered User Join Date: Nov 2002 Posts: 142	any ideas? did the link work this time?

06-08-2003, 11:21 AM	#5 (permalink)
FattyCBR Registered User Join Date: Oct 2002 Location: Towson, MD Posts: 524	Has your throttle body ever been removed? It's possible to put the gasket between the TB and plenum in backwards, which can cause a vacuum leak/problem. I'd say if you still have the code after replacing both O2 sensors than you definitely have a vacuum leak. __________________ Milan _ _ _ _ _ __ _ _ _ _ _ _ Support our troops! '98 4R Limited '82 Toy 4.3, SM465, D20 <- Sold

06-08-2003, 01:55 PM	#6 (permalink)
bamayote Registered User Join Date: Nov 2002 Posts: 142	thanx fatty never thought i'd ever say.......'thanx fatty". thanx for the reply....i'll go over it again. and no the throttle body has never been removed. and it idles fine........it idles around 6-700rpm. cya brad Last edited by bamayote; 06-08-2003 at 09:45 PM.

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06-06-2003, 01:37 PM	#2 (permalink)
Dr. Zhivago Away Join Date: Oct 2002 Location: Beaverton, OR Posts: 1,589	The link you provided does not work... So, I'm assuming that no one told you to clean the MAF Sensor. Also, check for vacuum leaks. I don't know what year you have, but I can guess that it is a 3rd Gen. Cleaning the MAF on a 99-02 is a really simple procedure, and not so much on a 96-98. Look into having the MAF cleaned or replaced and triple check for vacuum leaks. Even the smallest ones can cause this problem. Hope this helps. Dr. Z

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