sup, i just had my car tuned by a local tuner, and the air/fuel ratio at idle bounces from 16.9 all the way to 18 sometimes. But its mostly at 17.3ish. It just doesnt seem right to me. And the car misfires and coughs really bad under wot, but if the car is really warmed up like you've been driving it for like 20 mins on the highway, then it doesnt misfire.
He thinks the coils are going out.. the car JUST turned over 90K miles. and i just had the plug wires and coil boots replaced at 88K miles.
what do you guys think?

 

Doesn't sound like you have a very good tuner there.

 

x2
i cant read logs or anything but can u take some and post them for other guys to see?

 

Tuner is lost in the forest ..I would get it checked, might be your maf causing some issues there.Your car might be knocking too.I wouldn't go wot till you find the problem.

 

I think you just got untuned instead of tuned lol

 

Sounds like your injector scaling might be off, or there's a boost leak, or your gauge is not reading correctly, or......

Lots of possibilities, but that AFR is waaaaayyy too lean. Definitely needs to go back to the tuner to get fixed asap!

Also, if your coils, or any other spark related components were going out, then you'd most likely be running rich instead of lean, since the ignition system would not be adequately igniting all of the fuel being supplied.

 

i've never tuned a car before and even i know that your afr's are way too lean. put it back to stock or retune asap.

 

What's your tuner's number he sounds like a keeper?

Just kidding.

But seriously, your wideband sensor could just be going bad, however, due to the fact your car misfires and coughs, your gauge is probably right. Don't go WOT until you get a better tune.

It really sounds like Cali needs a good tuner.

 

Lean afr's at idle won't hurt anything but it should not be like that, whats you afr's like under wot?

 

i dont know i havent checked yet. And everyones telling me not to go wot haha. but ill find out.

 

Don't stay on the gas if you see afr's in the 12's or leaner!

 

Im going to call cobb in LA their supposed to be pretty good. hopefully they can get my car in good running condition

 

If you paid for that **** have him fix it or get some money back

 

I dont think his wideband is going out, if it was going out then the gauge would read nothing when full throttle... Thats how my wideband was, how old is your wideband?

 

well afr at idle is a bit lean however the car stays in closed loop at idle and cruise. So its possible on a long drive your trims change to be closer to stoich, however any throttle input which causes the car to misfire isnt good. However it could be simple issues: Like someone stated your injector scaling could be off? Or you plugs could be worn out or not gapped right. A boost leak would cause the car to run more rich and bog, You could possibly have a vacuum leak somewhere causing your issue, that would cause a car to run more lean. I think personally ditch the tuner, have someone who is knowledgable datalog your car and take a look at your map. Unless you can go to them, id do a remote tune. Before your engine hates you and breaks your wallet. Just my 0.02 good luck.