Code 91, O2's again??? WTF???

Hozer 88GTConv · 12-07-2006, 06:05 PM

Update:
The car is running like crap. It starts fine, but smells rich. Then, after it warms up, it's like a light switch. The timing goes wacky (on the PMS screen it varies from 15-ish to 32 degrees at idle!) and the rpm drops to 550 and it backfires.
Sometimes, if I shut it off and start it again, it acts normally for a while, then the condition returns. My brand new 02's read .00vdc at idle. As you might guess, it drives poorly. Hesitation, etc.
I got my wideband 02 bung welded on today and will install the wideband tomorrow or Saturday. The only code is 91, 02's reading lean...
thanks for any tips...
Hozer

Mustang Billy · 12-07-2006, 08:44 PM

Both the o2's should be switching realitively fast from lower numbers too higher voltage numbers...Make sure no grounds came loose or are coming loose...Check the EEC Ground bye the computer also that screws too the side floor of the kick panel...

Check EGR for smutt biuld up...Is that the only code...

12-07-2006, 06:05 PM	#1
Hozer 88GTConv Registered Member Join Date: Feb 2002 Location: Jacksonville, FL Posts: 706	Re: Code 91, O2's again??? WTF??? Update: The car is running like crap. It starts fine, but smells rich. Then, after it warms up, it's like a light switch. The timing goes wacky (on the PMS screen it varies from 15-ish to 32 degrees at idle!) and the rpm drops to 550 and it backfires. Sometimes, if I shut it off and start it again, it acts normally for a while, then the condition returns. My brand new 02's read .00vdc at idle. As you might guess, it drives poorly. Hesitation, etc. I got my wideband 02 bung welded on today and will install the wideband tomorrow or Saturday. The only code is 91, 02's reading lean... thanks for any tips... Hozer __________________ 1988 GT Convertible 331 10:1 TW heads, GT-40 intake, MSD, TRW flattops, B Cam w/ 1.7's, MAC exhaust, 24's, 70 TB, 76 MAF, 3.73's, Pro 5.0, Koni's, Anderson PMS, Wideband 02, yatta, yatta... One week with new motor, two speeding tickets...joy

12-07-2006, 08:44 PM	#2
Mustang Billy Registered Member Join Date: Dec 2006 Location: Houston/Conroe Tx,in the Piney Woods Posts: 19	Re: Code 91, O2's again??? WTF??? Both the o2's should be switching realitively fast from lower numbers too higher voltage numbers...Make sure no grounds came loose or are coming loose...Check the EEC Ground bye the computer also that screws too the side floor of the kick panel... Check EGR for smutt biuld up...Is that the only code... __________________ http://www.turbomustangs.com/feature_cars/mustangbilly.php Untimat Converter Concepts CamMotion C&S Specialties http://www.gofastfuels.com/cms/index.php?page=home One of the Fastest Stock E7 Headed 302's around.. With a Power adder@3000lbs 6.19@110.4 1/8 $100 Invested in total LongBlocks

Thread Tools
Show Printable Version Email this Page
Display Modes	Rate This Thread
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode	Rate This Thread:

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Code 81?? Code 51. HELP!!	blk88lx	Windsor Power	0	03-31-2004 08:22 PM
1972 Mach 1 "H" code but a 351CJ under hood?	757Driver	Classic Mustangs	1	09-16-2003 08:16 AM
code 15	tomazzzo	Windsor Power	1	06-06-2003 11:15 PM
Code 85...see if anyone can interpret	silver_pilate	Windsor Power	1	12-31-2001 06:24 PM
Code 81????	Chevyguy	Windsor Power	0	04-27-2001 10:44 AM