code 91, how to get rid of???
02-14-2004, 11:41 PM
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code 91, how to get rid of???
put a 98 gsr swap in my bro's 96 ek and cant get rid of the damn code 91, evap low pressure or something. anybody got any suggestions on how to get rid of this code?? trying to get the car ref'ed and dont think its gonna happen with the damn light on, thanks for any help provided
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03-08-2004, 09:08 AM
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Re: (Wild_one) code 91 fix
I dropped a 99 b18b in my 96 ek in November. I used the 99 ecu and it keep throwing code 91 fuel tank pressure sensor (FTP). My friend and i figured out that the ODB2A cars don't have the (FTP) and the ODB2B cars do. You can do a couple of things to get rid of the code. Use ODB2A or older ecu, thanks to trey 
i now know that you can turn your car on count to ten then start it and it will not throw the code, I know that you can also change out the gas tank for one with the sensor, But there is a better way you can trick the ecu into thinking the (FTP) is there.
Problem:
you need to get a grounded D15 pin out when tested with multimeter to read around 2.5 volts.
Supplies: tape, solder, one ecu pin, potentiometer (aka volume ****), and 3 wires (one Yel/Blu, one Lt.Grn, one Grn/Blk)
Explanation:
1.take the Lt. Grn solder to the ecu pin and to the potentiometer.
2.pin ecu pin out D15 with the Lt. Grn wire
3.take Yel/Blu wire solder to the Yel/Blu wire in ecu pin (D10) and to the potentiometer.
4.take the Grn/Blk wire and solder to the Grn/Blk wire in ecu pin (D11) and to the ground on the potentiometer. (the grounds is by it self)
5.use multimeter to set the potentiometer at approximately 2.5 volts.
6.tape up wires.
Caution: do not solder with the ecu hooked up could blow the ecu!
i now know that you can turn your car on count to ten then start it and it will not throw the code, I know that you can also change out the gas tank for one with the sensor, But there is a better way you can trick the ecu into thinking the (FTP) is there. Problem:
you need to get a grounded D15 pin out when tested with multimeter to read around 2.5 volts.
Supplies: tape, solder, one ecu pin, potentiometer (aka volume ****), and 3 wires (one Yel/Blu, one Lt.Grn, one Grn/Blk)
Explanation:
1.take the Lt. Grn solder to the ecu pin and to the potentiometer.
2.pin ecu pin out D15 with the Lt. Grn wire
3.take Yel/Blu wire solder to the Yel/Blu wire in ecu pin (D10) and to the potentiometer.
4.take the Grn/Blk wire and solder to the Grn/Blk wire in ecu pin (D11) and to the ground on the potentiometer. (the grounds is by it self)
5.use multimeter to set the potentiometer at approximately 2.5 volts.
6.tape up wires.
Caution: do not solder with the ecu hooked up could blow the ecu!
03-08-2004, 09:20 AM
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Re: (prjctCIVIC)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prjctCIVIC »</TD></TR><TR><TD CLASS="quote">would it help if i change out the stock fuel pump for a gsr one to resolve this problem???</TD></TR></TABLE>
will not help, cause i dropped a gsr in my ek without swapping fuel pump.
check ur wiring. maybe its wired wrong, i had no problems with this
will not help, cause i dropped a gsr in my ek without swapping fuel pump.
check ur wiring. maybe its wired wrong, i had no problems with this
03-16-2004, 06:34 AM
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Re: (96hatchback)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96hatchback »</TD></TR><TR><TD CLASS="quote">obd2b is 96-97 right?</TD></TR></TABLE>
6th gen Civic:
OBD2a = 96-98
OBD2b = 99-00
6th gen Civic:
OBD2a = 96-98
OBD2b = 99-00
03-30-2004, 08:54 AM
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Re: (97mini-me)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97mini-me »</TD></TR><TR><TD CLASS="quote">Did this using the potentiometer get rid of your engine light?</TD></TR></TABLE>
i used a 96 p72 instead of a 98 p72 and that is what solved the problem...
i used a 96 p72 instead of a 98 p72 and that is what solved the problem...
03-30-2004, 10:08 PM
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Re: (97mini-me)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97mini-me »</TD></TR><TR><TD CLASS="quote">Did this using the potentiometer get rid of your engine light?</TD></TR></TABLE>
Sorry, for the delay haven't checked this post in awhile, but yes it did. total cost was about $10.
Sorry, for the delay haven't checked this post in awhile, but yes it did. total cost was about $10.
04-04-2004, 01:14 PM
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Re: (John Conner)
I installed the volume **** yesterday. I fried two of them in the process, but the third one was a charm! It took care of my code 91. I thought I was never going to get rid of that damn thing! Thanks a lot!
04-07-2004, 04:24 PM
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Re: (John Conner)
My car was throwing code 91 and I preformed the potentiometer fix. When my car gets low on gas it will throw code 90 (Evap leak in canister area). If I fill my gas up and reset the light it will say off until the gas gets low again. If anyone else has this problem. I don't have a permanent fix for this but, I'm trying when i find one i will post it. Until then I'm keeping my gas above 1/4 tank.
Modified by John Conner at 12:04 PM 4/10/2004
Modified by John Conner at 12:04 PM 4/10/2004
04-09-2004, 04:02 PM
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Re: (John Conner)
I ran mine til it was almost empty and didn't throw that code. I flashed out the codes today and didn't get a code 90. Does it go away when you refill?? I did put gas in it before I checked the codes.
04-10-2004, 07:55 AM
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Re: (97mini-me)
If it didn't happen to you Mini-me i wouldn't worry about it. I'm going to check all-data today. To see if the exhaust manifold leak would cause it. <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by W C L »</TD></TR><TR><TD CLASS="quote">my boys had this problem.... check for exhaust manifold leak!!!!!</TD></TR></TABLE>
It might have just a coincidence that it happen when my gas was low a couple times.
It might have just a coincidence that it happen when my gas was low a couple times.
05-18-2004, 10:27 AM
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Re: (97mini-me)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97mini-me »</TD></TR><TR><TD CLASS="quote">I installed the volume **** yesterday. I fried two of them in the process, but the third one was a charm! It took care of my code 91. I thought I was never going to get rid of that damn thing! Thanks a lot!</TD></TR></TABLE> how can i obtain a volume **** part #? radio shack?
05-18-2004, 06:15 PM
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Re: (EE_Chris)
My buddy tried this procedure on his 98 EK and he's not getting CEL 91 anymore..but instead he's reading CEL for secondary o2 sensor, and CEL 92. When he takes out the ****...both these CEL doesn't apprear. He also tried using 2 differenty type's of 96 USDM GS-r ecu's and still it does not work. Check engine light 91 still apprears. What could be the cause of this?
05-18-2004, 07:04 PM
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Re: (slixxracing)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slixxracing »</TD></TR><TR><TD CLASS="quote">My buddy tried this procedure on his 98 EK and he's not getting CEL 91 anymore..but instead he's reading CEL for secondary o2 sensor, and CEL 92. When he takes out the ****...both these CEL doesn't apprear. He also tried using 2 differenty type's of 96 USDM GS-r ecu's and still it does not work. Check engine light 91 still apprears. What could be the cause of this? </TD></TR></TABLE>
The only thing I can think of is that the Ecu's that your friend tried are out of newer integra. As far as I know the 96-98 OBD2a Ecu's are not programed with the code 91 because the 96-98 cars don't have the FTP sensor, and the 99 and up OBD2b Ecu's are programed with code 91 because they have the FTP sensor. also try double checking your wiring.
The only thing I can think of is that the Ecu's that your friend tried are out of newer integra. As far as I know the 96-98 OBD2a Ecu's are not programed with the code 91 because the 96-98 cars don't have the FTP sensor, and the 99 and up OBD2b Ecu's are programed with code 91 because they have the FTP sensor. also try double checking your wiring.