So I lost my key so I took my car to the dealership to get a new key programs and also asked them if there was any available recalls or warranties on my car I didn't know about and they said there was a ECU recall and I had a free reflash as well as a new motor up to 100k miles.

So I had the key made and ECU reflashed. Car ran fine until I hit the freeway. Sudden bogging at 4.5k and 8k rpm and my Air fuel ratio gauge was telling me I'm leaning out like crazy. I never hit ideal or rich even for a second. First I think Okay 4.5k most likely the cat. But I kept thinking why is my AFR gauge reading lean so badly? Before when I'm cruising it's a little bit rich and when I stomp it's perfectly dead center ideal and would only go a little lean when I throw it into neutral or let off the gas suddenly. My CEL is also stuck on. My car is pretty much stock. Intake exhaust grounding kit coilovers. Nothing that would throw off a CEL.

Anyone else have this problem? I'm about to call the dealership tmmr to see what is up.

 

What kind of intake?

 

custom cold air. but I had it for over 6 months already I don't think it would act up now. All the stock lines are still on the accordion tube. VFlad has been removed.

 

I thought this behavior was expected for the first hundred miles driven on the car after a PCM flash.

 

I bet you that while they worked on your car they bumped something and you just have a vacuum leak under there somewhere.

 

Knowing what the CEL code is will help much.

 

it is you intake...... when they reflashed the pcm it erased all that data the pcm likes to keep..... drive it around a few times it should sort itself out or you need to check the design of you intake.... pipe size, screens, and what not..... what your saying sounds similar to what happened mine.... and that is what fixed it for me.... dont know if it will help but check it out.... oh and if it is what im thinking it is the cel will be maf related

 

I'm going to get the CEL code checked today hopefully if I can find a place that will check it for free. If not I'm going to call the dealership and ask them what is going on. Also my vacuum gauge is reading a steady 21 PSI like it always did before the reflash so I don't think it's a vac leak. But I'll check anyway.

 

If your VFAD is removed I would go back to your stock intake. Any "custom" applications are only going to cause problems with the mass airflow sensor which could be causing your driving issues.

The upper RPM stuff I'm not sure about but anything that's in closed loop will be effected by the fuel trims being reset with the flash.

Do you have screens in your intake? If not, that will cause problems.

If the tubing your using before the MAF is larger (most likely) it could cause lean problems in the upper RPM area.

Either way, the stock intake is perfectly fine and does not need replacement. It's got a huge filter surface area and flows all the air you need. It's not glamorous but it works.

Edit:

A vacuum leak is also possible and will cause overall lean conditions.

 

intake tubing is 3''

but either way wouldn't it have caused problems a long time ago.

 

Just reset the ECU and did the 20 brake tap. Still the same. CEL was off turned on after a few minutes.

 

Depends, when was the last time your PCM was reset or battery had been pulled for a couple hours?

If you're getting a CEL however that points to a different issue. If it's a vaccum leak you might be getting a too lean CEL.

Either way, pulling the code would be the first step as it will narrow down the issue.

 

Since the intake my battery was pulled 3 or 4 times. for a few hours I'm ordering a OBD2 reader tmmr so I can find the exact codes. It might just be a dying cat..