DaddySS

For all of you have installed headers (with cats)and are throwing codes - 0133, 0134, 0135, 0141, 0153, 0154, 0155, 0160, 0161, etc.

I have seen many posts where we are trying to figure them out but I haven't seen many "permanent" fixes - unless we are so glad to get it resolved we don't bother to come back and post the solution.

My question is then, have you solved the problem without deleting the code via LS1 edit, or replacing the sensor with an 02 sim, and if so what are (were) the solutions?

NoGo

iTrader: (2)

On some of the cars where the problem is cronic, I will kick the car to open loop and run them without oxygen sensors. This solves ALL the problems.

Open loop seems to be taboo amongst people here, but all cars over in the middle east run open loop from the factors with NO problems.

Good Luck,
Kevin

<small>[ March 15, 2003, 07:25 PM: Message edited by: NoGo ]</small>

DaddySS

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by NoGo:
<strong> On some of the cars where the problem is cronic, I will kick the car to open loop and run them without oxygen sensors. This solves ALL the problems.

Open loop seems to be taboo amongst people here, but all cars over in the middle east run open loop from the factors with NO problems.

Good Luck,
Kevin </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks for the reply - can you help me to understand what open loop means and how it works with the PCM?

Also, I assume by what you're saying that some cars with headers don't have these problems. Wouldn't that imply that there is a way to solve them?

NoGo

iTrader: (2)

Some cars don't have the O2 problems because of different exhaust system designs. It depends on the exhaust header, merge collector, Y-pipe, and muffler that is used.

Open loop is computer operation without referencing the O2 sensors. This means that your car is going to try to target a specified a/f ratio without any feedback from the O2 sensors. This mode is actually more condusive for making power (because there is no power enrichment, your car holds the same a/f ratio all the time). The downfall of this mode is gas mileage. In open loop your car will run enriched (ie roughly 13:1 instead of the usual 14.8:1). Additionally, you cannot pass emmissions with the car stuck in open loop.

The benefits of open loop are that you no longer have to run O2 sensors. Without O2 sensors there are couple advantages.
1) You can run leaded gas. This is a big advantage if you ever want to run race gas. Leaded vs Unleaded race gas is much cheaper.
2) You don't have any of the headaches that are associated with O2 sensors. Including the above mentioned problems.
3) No more LTerm crap. You no longer have to worry about your LTerms messing up your tune because they will always be locked at zero.

Before putting your car in open loop, I recommend making the necessary adjustments to your injector flow table to get your LTerms close to zero (they don't have to be near exact, but ~+5 to +10 is preferred for running conditions). Once you have done this, your next tune you will want to kick the car to open loop. To kick you car to open loop multiply the "Open Loop Enable Temp" table by 300 percent. This will do the trick and lock the car in open loop permenantly.
Once done, eliminate any O2 or Cat SES code that can be set. After this, remove your O2 sensors because you are no longer using them.

Again, this method works, but should only be used if you are not concerned with emmissions, you have no cats on the car, and your exhaust is modified.

Good Luck,
Kevin

DaddySS

Kevin: Excellent response and I really appreciate it.

I am encouraged by your statement that some cars don't have the problem, which would imply that I can get these resolved.

I have the TTS headers and GMMG, a combination that should be as manageable as any other.

I do run cats and I have to pass emissions so going open loop is not a choice for me.

The problem is not chronic (yet), since I am only thowing the 0135 and 0153 codes occasionally, and I haven't spent enough time trying to get them resolved.

You are clearly well versed in tuning these systems, where in Connectcut are you?

Thanks again for your help.

NoGo

iTrader: (2)

We are located in Wallingford CT, Exit 14 off of I91.

There are some solutions for the codes that you are seeing, but none of them are 100% (ie pushing the O2 sensor further into the exhaust, coating the headers, etc...)

DaddySS

Wanted to give an update. After several days, the car settled into throwing the 1153 codes on every run. Took it to the dealer and they scanned it and said all 4 02 sensors were bad. Replaced all 4 so we'll see. So far, 4 runs and no codes.