PO 1133, GM experts any advice??

Status
Not open for further replies.
D

dailydriver

Joined
Mar 14, 2006
Messages
9,619
Location
The only Ivy League town in Joyzee
I get an occasional PO 1133 (driver's side pre-catcon 02, insufficient switching) on the car in sig.
STOCK; exhaust manifolds, EGR system, A.I.R. system, fresh plugs/wires, new MAP sensor, new PCV valve, air/oil separator, new intake manifold/TB gaskets, sparkling clean TB/MAF sensor, and intake manifold, and more I forgot now.
NO OTHER codes appear at the same time, or at all.

It sometimes stays off for a month or so (~750 miles+), so it is for many start/warm up cycles, after resetting.

A few times it comes right back within a few miles (VERY few warmup cycles) after resetting.

This is with a BRAND NEW NTK O2 sensor installed, and both with and without the injector slopes run lean.

The SES light usually comes on during steady state highway driving at ~1750 rpm in sixth gear.

ANY ideas (preferrably from LSx engine, GM techs, domestic bashers need not apply)??
 
Boy that's a weird one. Not seeing many of those around here.

Good luck. Remember that wiring and plugs, connectors, etc., are always suspect, too.
 
Did you have the problem before you put on the new O2 sensor?

I've had many 02 sensors fail on mine, pre- and post-cat. I've always just replaced them and the fault codes went away.
 
Originally Posted By: A_Harman
Did you have the problem before you put on the new O2 sensor?


Yes, it was doing the same thing with a < one year old Denso O2 (changed when I replaced the catcons, since I wanted to start fresh) which is the reason I replaced that one.

If I am not burning oil, and not adding a lot of fuel additives, what else in the mixture could cause this??

Could a too lean/high NOX exhaust flow trigger this code?

There are no exhaust leaks that I can see or hear. (New manifold collector to catcon in-pipe gaskets as well, but not new actual manifold to head gaskets.)
 
If the ECU is saying that the O2 sensor is not switching enough, that makes me suspect something is wrong in the circuit. Bad sensor, pinched wire, bad connector, etc. Since you have put in a new sensor, maybe there is some other problem in the circuit, like 4x4chevydude was suggesting.

As another diagnostic, you could interchange the O2 sensors from side to side, just to see if the code follows the driver-side sensor to the passenger side. But since the sensor is new, the chance of it being bad should be very low.
 
I was going to recommend making a pig tail to hook up one to side the other. You know make the left bank the right bank and the righ bank the left bank and see where that get you.
Sounds like it may be wiring problem.
 
I would suggest you start with the simple stuff first:
-Verify that the wires haven't gotten too close to the exhaust and burned off their insulation.
-Verify that the connector is fully seated and doesn't have any sort of oil or grease in it.
-Verify that you don't have any coolant loss condition.
-If you use any underhood dress-up chemicals, discontinue use for now and rinse away what you can with a bucket of hot water and dish detergent.
-If available, use a scan tool to observe long term fuel trim for both banks at warm idle, at 2500RPM in neutral, and during steady state cruise at highway speed.
 
How about some history, in a later post you stated new cats? Why? In our shop we are more and more using OE only when it comes to sensors and cats. I would be suspect of anything that is not OE. If you have access to a scanner it would help if you could post long and short fuel trims.
 
Originally Posted By: crazy8
How about some history, in a later post you stated new cats? Why? In our shop we are more and more using OE only when it comes to sensors and cats. I would be suspect of anything that is not OE. If you have access to a scanner it would help if you could post long and short fuel trims.


The catcons would have no bearing whatsoever on this code since it is for a pre-catcon O2 sensor.

Now if you are asking about a problem which necessitated the replacement of the catcons in the first place; I wanted to replace 125K mile + converters in order to start fresh (and yes, was also getting an occasional 420/430 on those).

YES, this might have been a mistake since I went with 49 state, direct fit, Magnaflows before realising my car is a CARB calibrated ECM parameter '50 state' setup, and I always thought that CARB cars were ONLY sent to Cali!
frown.gif
mad.gif
 
Originally Posted By: yonyon
I would suggest you start with the simple stuff first:
-Verify that the wires haven't gotten too close to the exhaust and burned off their insulation.
-Verify that the connector is fully seated and doesn't have any sort of oil or grease in it.
-Verify that you don't have any coolant loss condition.
-If you use any underhood dress-up chemicals, discontinue use for now and rinse away what you can with a bucket of hot water and dish detergent.
-If available, use a scan tool to observe long term fuel trim for both banks at warm idle, at 2500RPM in neutral, and during steady state cruise at highway speed.


The wires are all routed away from the exhaust, AND covered in split wire covering which are then wrapped in silver DEI heat reflective/proofing tape.

The connectors were sprayed with the CRC electrical connector cleaner (forgot the name) and air dried before re-connection, and triple checked for seating.
wink.gif


The coolant level has been perfect since new, and there are NO air bubbles, or any foaming in the tank/radiator.

I never have, nor ever will use underhood dress-up chemicals, and only used Gunk degreaser once, a LONG time ago.

I have a PLX Kiwi wifi OBD 2 plug-in device, along with a Dash Command app for the iPod which has a real time fuel trim display on that screen, so I will check that out, THANKS!
thumbsup2.gif
 
What are the fuel trims? ST and LT if you can get them for each banks.

Is the MAF OEM? When was the last time you had the fuel system cleaned?
 
Last edited:
Originally Posted By: mattd
What are the fuel trims? ST and LT if you can get them for each banks.

Is the MAF OEM? When was the last time you had the fuel system cleaned?


I have not had a chance to get the fuel trims yet.

Pure stock MAF with screen still in it.

I change the fuel filter every year (~10K miles), it has brand new, flow matched, stock lb/hr injectors in it, and I use a full bottle of SI-1 twice a year, and a small maint. dose of this cleaner (~2-3 ounces) at every fillup (17 gallons).
 
Originally Posted By: Jim Spahr
Try an OEM AC Delco or Delphi O2 sensor. Sometimes the aftermarket O2's do not work well with GM cars.


Even though NTK, and/or Denso are the (only??) companies which actually manufacture them for Delco and Delphi??
 
Status
Not open for further replies.

Similar threads

S
  • Locked
98 Volvo V70 T5 PO455 Code Resolution
Replies
5
Views
15K
sleddriver
Back
Top Bottom