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182 Posts
Discussion Starter · #1 · (Edited)
Its a 90.

Modded exhaust, now SES EGR code 32 ??

Gutted the pre cats, did it on the car. Opened the bottoms with a cut off wheel on a 4" angle grinder. cut 2"X5" openings, cleaned out the cats then welded patches on. This was the quick way, header install is planned for winter so the head pipe will be thrown out.

Pulled the main cat & fabricated a test tube with air pipe.

I am pleased with the performance gain however the SES light for the EGR has me wondering what went wrong.

The battery was disconnected the entire time during the cutting & welding phase.

Nothing was changed on the motor.

Anybody have a fix or suggestion?


138 Posts
Your exhaust is running cooler now,the loss of backpressure is keeping the o2 sensor from heating up, ya didn't do anything wrong. Every now & then the ecm will do a check on the 02 sensor when the egr opens,if it doesn't like what is sees it will throw the egr code even tho the egr is fine.

182 Posts
Discussion Starter · #3 ·
Thanks for your response Overdrive.

I have a heated O2 on the shelf that I was saving for the header install, might as well get it wired in now & see if it helps.

64 Posts

That is exactly the problem I have been having for almost a year now, and looks like that heated O2 sensor is going to be my fix.

My question on this is, which O2 sensor to buy for that to work? since the one I have found says something like 94 front and 96 rear... would that work?

Thanks guys!

By the way was the cat in the middle of the car empty when you opened it up?? mine is...and dont know if should be...

182 Posts
Discussion Starter · #6 ·

By the way was the cat in the middle of the car empty when you opened it up?? mine is...and dont know if should be...
My cat was intact. A previous owner gutted yours.

Here is the info I used for the heated o2 sensor posted by Flame Red, possibly on another forum.

that have installed long tube headers may find that their engines are
running in opened loop because the O2 sensor is not heated to 600 degrees.
This is especially true if the O2 bung is relocated to the collector. In
the case of the Hooker 2149 header, the bung is located on the #7 tube out
of the box. This makes the stock O2 sensor work properly, however, the
sensor is only measuring the gases from one cylinder, which can be

Thanks to the help of many forum members, here is some
helpful information that may ease the pain of converting the standard O2
sensor to a heated one.

Parts required:

* Bosch O2 Sensor.
This sensor is AutoZone part number 13190 and costs $43.99. This is an
Autozone part number not a Bosch part number.
* 3 Female Terminal
Tower. This is available at Pep Boys Part number 85392. It costs $7.99.
The are a couple of these available This one has leads. There is another
that has no leads and you must puchase leads, insulators, etc.
* 1
Female Terminal tower, which can be cut from old O2 sensor or a new one
can be purchased at Pep Boys.
Miscellaneous wire, insulation, crimps,
tie wraps.

Tools Required: 7/8” wrench, pliers, 10mm socket,
crimp tool, wire cutters, wire stripper.


For those that are anal about proper procedure, disconnect positive
battery connection. For the rest of us, go to step 2.
2. Disconnect
old O2 sensor feed wire by carefully disconnecting clip.
3. Use
7/8” wrench to remove old sensor.
4. Install new sensor. Sensor
has anti-seize on it already. Tighten with 7/8” wrench.
Cut lead from old O2 sensor so you do not have to mangle your car’s
wiring harness. If you prefer to keep your original O2 sensor whole, you
can purchase a new single connector from Pep Boys.
6. Connect 3
female tower connector to new O2 Sensor.
7. Crimp the old lead from
the old O2 sensor to the wire on the 3 female tower connector that
corresponds to the black wire of the new O2 sensor. Insulate well with
high temp insulation!
8. Connect the old sensor lead now coming
from the black wire of the new O2 sensor to the car’s O2 sensor
9. The other two wires of the new O2 sensor are white.
Connect one of the corresponding wires to ground. It does not matter which
one. There is a convenient 10mm bolt that connects to the engine just to
the rear of the oil filter. This is a good ground.
10. Cut an
appropriate length of (red) wire and crimp to the other corresponding
white lead of the new O2 sensor. Insulate the connection.
Connect the other end to your favorite 12V source that is ignition
activated. There is a good source on the Fan Relays that is ignition
12. Tie wrap everything out of the way from the
intense heat source of the header!

Enjoy! You car will behave much
better, at least mine did! No more constant running rich :) due to
constant open loop.

Flame Red

64 Posts

So I went and bought the Bosch heated O2 sensor, here is spain which is 100 euros insetead of 40 usd, but oh well... I will do anything if it fixes it!
Installed it as described above and... NOTHING! it runs just like it did without a heated O2.
Gives me a code 32 at the exact same time and distance from the house as it has been giving me for a year now.

Next thing Im going to try is, since I am going to the US soon I will by, pre-cats and the big one in the middle, since mine seem to have been gutted although no signs of cutting and weldding. The new cats should give me backpressure needed to run correctly?? you think??

Another question is, will a piggy back chip get rid of the problem? or would I need someone to burn me a new one without codes or stuff like that??? in that case who could do it???


64 Posts

There are two big numbers on that box:

0 258 003 995-OBO and 3165143092514

Dont know which one it is exactly...

Should this heated O2 fix the entire problem? no need for back pressure at all?? because my Cats are al completly empty...
Thinking of buying the big one in the back, should that create enough back pressure for EGR to work??


108 Posts
I recently gutted my pre-cats and also the main cat - they are now just hollow "cans". As result of this I did not get any codes.

But we managed to break the EGR solenoid earlier when changing the thermostat and that has given code 32 because of that ever since. I'm getting rid of EGR and AIR completely during winter and burning a new chip with EGR unchecked (or whatever the correct term is... :toilet
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