My Exhaust seems to be popping lately on the rev down, and I think I may be running rich. What's the easiest way to tell if I am running rich other than pulling my plugs, or is there one? I guess I can always go pull a plug and check. Also, what could cause the exhaust to pop? Thanks in advance for any reply. ------------------ Smile, you're in my rearview I'm joking, I have a v6. See pics @ Billy's Firebird 92 Bird 3.1L Auto Best $750 I ever spent.... DRIVE IT LIKE YOU STOLE IT! Kills: 93 Mustang LX (Before Mods),98 or 99 Dodge Stratus (tough one, edged out at 40), 92 Camaro RS 305 TBI-Not too fair, his fuel pump went out 2 days later. Nice car, but not running right. 97+ Honda somethin or another...modded....kept at my door the entire way Close Calls 94 Grand Am 3.1 V6, 92 Cavalier 3.1 V6 01 Porsche 911 Turbo (Had em till first gear) Mods-Jet Stage 2 Performance Chip, Accel Cap/Rotor, Accel 8.8 MM Wires, Accell Coil, AC Delco Rapidfire Plugs, Dynomax Catback, K&N AIM name OVRCLCK350

Exhaust that backfires during decel is a good indication of a rich condition....BUT, check your A.I.R diverter valve...mine was causing a backfire before I ripped the whole system off. I just left my Air pump that I directly connect to the inlet tube that runs down to the cat for emission tests....works like a charm, and plug changes are MUCH easier.
: )

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89 GTA G92
305 TPI WC 5spd w/3.45
Accel Cap & 8mm Taylor's
Custom 4" Cold Air Induction
Jet Airfoil
K&N Airfilter
160 deg stat/fan switch TB Bypass - Steel Rad
Cat back 3" Exhaust w/Terminator Muff.
HiGh FlOw Dynomax Cat
Spohn LCA's - KYB GR-2's
Moroso Crank Bolt and roller pilot bearing.
Autometer Vac+Oil Temp

I know my plugs aren't bad, I was just going to look and see if they have any color indication of rich.

To elaborate on what Steve said:

"an indication of a rich condition" but specifically, under those conditions. It may be fine all the rest of the time but only rich when decelerating. So you rplugs may not show a thing.

Carb cars are particularly prone to this, because the idle circuit is active when decelerating, and it's pretty hard for the carb to "know" when it should or shouldn't feed extra gas based on the manifold vacuum (which is the only thing that "tells" the idle circuit how much gas to feed). But in a FI setup, that can be readily adjusted with programming. I notice you have a chip in your sig....

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