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2009 xrs "too lean"

1411 Views 10 Replies 6 Participants Last post by  FlameyFart
i installed an injen cold air intake into my car a couple months ago and about a month ago my car started to worry my a little. to date i have about 17k miles on it thats it! and now when im idling or slowing down the car either fights me back a little bit or shuts off..i took it to a valvoline that my friend works at and the reading said the system was too rich as well as too lean..its clearly cause of the intake but my carr runs perfect once i get moving and up until im under about 10 mph i dont know what to do some help!?!?!?!?
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might wanna mention if its auto or manual
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Sounds like a mass air flow sensor issue to me
What is the internal diameter of the intake? It has to match the factory specs or the readings will be skewed.

I do not understand why so many on this site cannot comprehend this element of tuning. An intake nine out of ten times needs a tune. Its not a true 'bolt on'.
most likely its a MAF sensor related issue, have you also serviced your filter recently? it might be overly dirty causing inconsistent airflow.
most likely its a MAF sensor related issue, have you also serviced your filter recently? it might be overly dirty causing inconsistent airflow.
Almost definitely a MAF/intake issue. If he has only had the intake on for 2 months and the problem stated a month ago I would say that could be ruled out (unless he drives insanely high miles), but who knows.

OP, do you have any CEL codes or did you friend just log the car to find the fueling issues by the A/F ratio?
im not exactly sure what the diameter is i will find out, but the injen fits in very different than the stock intake does..also the injen supposedly comes "tuned" already so i never thought different
also im not sure of the codes that came out yes my friend just loged up and scaned through it
im not exactly sure what the diameter is i will find out, but the injen fits in very different than the stock intake does..also the injen supposedly comes "tuned" already so i never thought different
Just take a tape measure and measure the MAF housing ID and then the stock MAF housing ID. If they are different then the MAF needs to be scaled or you will always have rich and lean conditions. Most just deal with it, but you really shouldn't if you want the intake to actually make a little more power and you want your car to last. Also, the intake itself cannot be tuned, the cars ecu must be tuned.
Just take a tape measure and measure the MAF housing ID and then the stock MAF housing ID. If they are different then the MAF needs to be scaled or you will always have rich and lean conditions. Most just deal with it, but you really shouldn't if you want the intake to actually make a little more power and you want your car to last. Also, the intake itself cannot be tuned, the cars ecu must be tuned.
ID = Inner Diameter, if someone is wondering
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