[mmmnot]

Hello all.

I have been getting a service engine light soon. Upon scanning with the Bav tool, I pulled up this error code: 29f5

Image:


I have AFE Catted primary headers and 2nd cat delete.

This is the second time I've had to run this code in the past month. Prior, I had one more similar issue, but it was after a dyno run (with headers/post 2nd delete) about 4 months ago.

There are no rear sensors and AFE claims no issues, so I have a few possibilities:

A.) sensors are bad due to higher flow?
B.) bad gas?
C.) o2 sensor is not properly seated or in the middle to get an accurate flow reading

Does anybody have an idea where I should start? Would this cause emissions issues in a fairly liberal state, eg NOT CA.?

My gut says just toss a spacer between the o2 bolt to center it more...

Can o2 sensors be cleaned? If so, is it advised vs. just replacing?

Any guidance or help is greatly appreciated.

Thanks!

PS, I did search and found a thread here http://www.e90post.com/forums/showthread.php?t=555468 but it seemed to offer no real solution with the above modifications.

[MarkkyyMan]

29F5= Catalyst System Efficiency Below Threshold (Bank 2)

[SDemetris]

What do you mean there are no rear sensors.. there absolutely are

[mmmnot]

Originally Posted by SDemetris

What do you mean there are no rear sensors.. there absolutely are

Sorry, I meant secondary cat sensors?

[thomas88162]

The rear O2 sensors (post-cat) ARE what sets these codes, they compare the fuel content to the reading from the pre-cat O2 sensors. Assuming that you mean there are no rear O2 sensors, you either need to tune accordingly or get yourself some.

[mmmnot]

Originally Posted by thomas88162

The rear O2 sensors (post-cat) ARE what sets these codes, they compare the fuel content to the reading from the pre-cat O2 sensors. Assuming that you mean there are no rear O2 sensors, you either need to tune accordingly or get yourself some.

OK, maybe I am confused. Let me rephrase here:

Both of my primary cats are in place with sensors.

However, I did delete secondary cats which has no sensors or wires plugged into them.

Does your above comment still apply or did I just confuse everybody with my wording?

[Ali-E90]

I'm a bit confused by the earlier post also... I always thought that there were no sensors after the 2ndary cats, meaning they could be deleted without worry of any codes.

Is this assumption incorrect?

[mmmnot]

Originally Posted by Ali-323i

I'm a bit confused by the earlier post also... I always thought that there were no sensors after the 2ndary cats, meaning they could be deleted without worry of any codes.

Is this assumption incorrect?

Right. That's what I assumed/knew based on research:

Primary, back diagram indicates no wires, and I can confirm this as I did the install with the 2nd cat delete:



No. 2 in the above diagram.

While my AFE headers retained all of the sensors from the below diagram:



Vs AFE header:



Which have the same placement (or similar) of sensors.

It's worth noting I've driven over 100 miles since my last code deletion with no more errors. It seems to be very, very random...

[thomas88162]

Okay, now I understand. You just deleted secondary cats, but have pre and post cat sensors for the primary(there are no sensors for the secondary). I was sort of confused as to whether you were missing O2 sensors. Placement of the O2 bung could cause an issue like this, but I wouldn't think AFE would have such an issue.

[mmmnot]

Originally Posted by thomas88162

Okay, now I understand. You just deleted secondary cats, but have pre and post cat sensors for the primary(there are no sensors for the secondary). I was sort of confused as to whether you were missing O2 sensors. Placement of the O2 bung could cause an issue like this, but I wouldn't think AFE would have such an issue.

Yeah, sorry for my mis-wording.

Anybody have any ideas where to start looking?

Is it advisable to clean the o2 sensor, if so, what's a proper product?

[thomas88162]

Usually if O2's are bad they are simply bad, no cleaning would work. But, I see no reason why yours would be defect so soon other than installation damage.

[mmmnot]

Originally Posted by thomas88162

Usually if O2's are bad they are simply bad, no cleaning would work. But, I see no reason why yours would be defect so soon other than installation damage.

Thank you for that information. It has yet to pop back up. I'm going to assume it's just bad gas. I'll have my local shop take a peek at it during my next oil change.

Just wanted to see if it was something obvious I might be neglecting.

[xavi718]

Originally Posted by mmmnot

Thank you for that information. It has yet to pop back up. I'm going to assume it's just bad gas. I'll have my local shop take a peek at it during my next oil change.

Just wanted to see if it was something obvious I might be neglecting.

Did you solve your problem? After I installed my AFE HEADERS 4 months after i get the service engine soon .

.