No way, sounds like changing the plugs are a temporary solution. I'm glad you changed them anyway.
A cracked, broken, fouled, or missing plug wouldn't do what he's describing. His car dies. Powers down he says. A misfire would just be sputtering and slow. .
Spark plugs just provide the spark. Fouled black tips mean rich and one cracked possibly from heat of detonation? Faulty injector?
Then you replace them with brand new clean spark makers, 100% more effective than the ones you've just removed. Wow, the Supra is great now. Thanks guys!
2 days later.... "Check engine light" (I'm reading your future now.)
New o2 sensor has been blasted with rich exhaust for a few days and throws a check engine light. Possibly the AFM threw the check engine light at fuel cut for being maxed.
When you throttle and hit boost it dumps 11.2:1. Way too much fuel for the amount of air compressed during the early stages of spool. The AFM is maxed and the ECU Cuts the fuel and you get a reading of 16:1 so a rod doesn't go through the block.
My guess is you messed with the fuel regulator in some way. Perhaps you just crushed the stock one in too far delivering too much fuel at pressure or you have some sort of aftermarket regulator you installed to adjust but not sure how. Or the boost is maxing out your AFM.
No one gets an AFR gauge all by itself without knowing it'll begin saying some other AFR than what is stated in the manual.
Your Supra's AFR should be not less than 13:1 at 8PSI boost, full throttle. For the set up you have. Normal cruising should be anywhere from 14.2:1 to 14.8:1. maybe leaner I don't completely remember, my car hasn't been stock for a while. Slow deceleration can go to 16:1. 17:1. Foot off gas will pin at 21:1 the Widebands' limit. Half throttle into boost should be around 13.5:1 or 14.0:1 and can drop richer as the boost increases.
There i cut it down for you, in the daylight it did seem a bit rambling. Holy.
A cracked, broken, fouled, or missing plug wouldn't do what he's describing. His car dies. Powers down he says. A misfire would just be sputtering and slow. .
Spark plugs just provide the spark. Fouled black tips mean rich and one cracked possibly from heat of detonation? Faulty injector?
Then you replace them with brand new clean spark makers, 100% more effective than the ones you've just removed. Wow, the Supra is great now. Thanks guys!
2 days later.... "Check engine light" (I'm reading your future now.)
New o2 sensor has been blasted with rich exhaust for a few days and throws a check engine light. Possibly the AFM threw the check engine light at fuel cut for being maxed.
When you throttle and hit boost it dumps 11.2:1. Way too much fuel for the amount of air compressed during the early stages of spool. The AFM is maxed and the ECU Cuts the fuel and you get a reading of 16:1 so a rod doesn't go through the block.
My guess is you messed with the fuel regulator in some way. Perhaps you just crushed the stock one in too far delivering too much fuel at pressure or you have some sort of aftermarket regulator you installed to adjust but not sure how. Or the boost is maxing out your AFM.
No one gets an AFR gauge all by itself without knowing it'll begin saying some other AFR than what is stated in the manual.
Your Supra's AFR should be not less than 13:1 at 8PSI boost, full throttle. For the set up you have. Normal cruising should be anywhere from 14.2:1 to 14.8:1. maybe leaner I don't completely remember, my car hasn't been stock for a while. Slow deceleration can go to 16:1. 17:1. Foot off gas will pin at 21:1 the Widebands' limit. Half throttle into boost should be around 13.5:1 or 14.0:1 and can drop richer as the boost increases.
There i cut it down for you, in the daylight it did seem a bit rambling. Holy.
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