AFR's jumping like crazy!! HELP!
#1
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AFR's jumping like crazy!! HELP!
So i just put my turbo kit in this past weekend and got it all set. If this makes any difference i bought it used and everything seems to be working alright.
The problem is the AFR's are constantly jumping between 13-16 just cruising and when i let off the gas it goes all the way to the right like past 18. Even at idle it is jumping from like high 13's to like 15.5. sometimes jumping to the 17's.
I am running off the tune that the previous owner had, just for now. I was just wondering what this might mean. I don't get that bad of back firing maybe once in a great while. I also have the stock plugs in, but not for long. I have only takin it on one real ride so far and i just got the colder plugs and will be putting them in ASAP, but not sure if this is my problem. I will also be getting it re-tuned for my car.
Just wondering what the problem is and if any of the things i have yet to do will fix it. Or is it something serious.
ALSO! just to throw this out there but if there is anybody in the RI area that could help me install my turbo timer that would be awesome. Right now I'm just letting it idle for like 8-10 mins
The problem is the AFR's are constantly jumping between 13-16 just cruising and when i let off the gas it goes all the way to the right like past 18. Even at idle it is jumping from like high 13's to like 15.5. sometimes jumping to the 17's.
I am running off the tune that the previous owner had, just for now. I was just wondering what this might mean. I don't get that bad of back firing maybe once in a great while. I also have the stock plugs in, but not for long. I have only takin it on one real ride so far and i just got the colder plugs and will be putting them in ASAP, but not sure if this is my problem. I will also be getting it re-tuned for my car.
Just wondering what the problem is and if any of the things i have yet to do will fix it. Or is it something serious.
ALSO! just to throw this out there but if there is anybody in the RI area that could help me install my turbo timer that would be awesome. Right now I'm just letting it idle for like 8-10 mins
#6
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Originally Posted by java09
8-10 minute IDLES???? hahah thats too long for our cars at such low boost levels.. 1-2 mins tops!
#15
Depending on how wide they swing its normal, when the car is in closed loop mode it uses data from the 02 sensor to correct the afr. So in essence what happens is your ecu and piggyback tell the car to inject a certain amount of fuel which gives you a resulting afr of say 14.0, than the computer realizes this is rich and corrects by leaning out and jumping it up to 15 or so, than back to rich to correct for that, etc. If its too wide, your fuel trims are probably set to high in the fic for vacuum (cruising) thus the factory ecu and o2 sensor is having to overly correct causing very large jumps, if the fuel trims under vacuum are off ive seen it swing from 13.5 to 16 and back and forth over and over
#17
Originally Posted by Boi
whats the ideal afr at wot for the scion tc anyway?
#19
yeah it should be tune related, and plus a BOV vented to atmosphere could add to that.. as long as it doesnt stay lean when you hit boost you should be good, what you should keep your eyes on is the boost afrs since you are untuned dont let it stay above 12.5 when you boost
#20
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yeah i reset my ecu and it seems to hold steady at like 13.6ish at idle and it does go lower during boost but i tend to keep my eyes more on the road haha. At cruising it also tends to stay in the 13's. Occasionally it will jump around but only a little. Also when i let off the gas and still in gear the gauge goes all the way to the right and the three dots come up is that normal? Also i can hear my turbo spooling before my boost gauge is even at 0. j/w if this is norm. It's my fist time boosting a car and i am a little nervous... as you might be able to tell. Just wanna make sure nothings wrong.