I just got a new clutch and flywheel installed. AFRs were normal before I brought it into the shop. After I get the car back, the car is running lean at idle and cruising(dont want to go into boost since its a new clutch). Idle is reading over 18 and cruise is mid to high 15s. Shop told me I would be fine driving it home and that they would check it out tomorrow. What could be causing this; how could this be related to a clutch install? They dont seem to know what it could be. Said they preformed a boost leak test. Will I really be fine driving it like this as long as I dont get on it?

Car is e85 plus bolt ons

 

clutch has noting to do with your AFRs maybe some kind of vacuum leak check everything i am sure when they were putting it back they left something loose or disconnected

 

Yeah, they probably loosed or removed something to get it out of the way and never replaced it. I can't see what that would be that would cause your car to lean out, but that's my guess.

Also, this is why it's important to take your car to a shop that specializes in them to get work like this done. I learned from owning a B5 S4 that although the shop might have seen the 1.8T or 2.0T come in every once in a while, their faces would go blank when they popped the hood on the S4. I would get half assed jobs, unfinished jobs, problems they couldn't figure out, etc., so I started either doing the work myself or taking it to a shop that specializes in European cars, mainly VW/Audi/Porsche and the car started to smile again.

 

They need to do a boost leak test, and fix any boost/vacuum leaks...

 

Thanks for the answers. Yea I did take it to a performance shop that has worked on evos.

They did do a boost leak test but said they didnt find any leaks. I will be bringing the car back to them soon. My tuner said the car should be fine to drive in the meantime as long as the CEL doesnt start flashing.

 

Exhaust leak? Where is your wideband sensor located?

 

x2...

 

Ive never set eyes on it myself but it should be on the downpipe.

 

Take it back, don't drive it lean

 

either an exhaust leak or vacuum leak.

 

Does your car have a dual map? If so, it could be running on the premium gas map. I always have to check this every time after I finish a job.