verbs

I'm on the verge of using header wrap as a last resort to keep my o2 sensors heated up enough to stop me from getting heater codes, which in turn cause the o2's to insufficiently switch.

Is there a way to wire my car so that the o2 sensors get more power allowing them to maintain proper operating temperature, or is there a way for ls1 edit to do this?

Anyone?

I really don't want to destroy my nicely coated headers with header wrap.

Speartech

iTrader: (14)

I don't know anything about your setup, or if you have always had this problem, but a few things come to mind.

1. Bad O2 sensors (old, faulty heater, worn out, etc.)

2. Wiring problem (high resistance connection to the heater part of the sensor, corrosion in the connectors, blown fuse, etc.)

3. You're too far downstream with the sensors to keep everything within the specified diagnostic parameters.

On pre-OBD2 systems it was not unusual for a car to pull up to a stoplight and fall back into open loop for this same reason. Most O2's were 1-wire, unheated sensors and it was just accepted that under low flow conditions, the sensors cool off and the car may drop out of closed loop.

I guess the point is that if your sensors are good, and your wiring has NO high resistance connections in it, turning off the heater codes with LS1 Edit could be a solution. Your closed loop mixture control is probably great when the engine is running some RPM, it's probably just a situation that is happening at idle.
Just a thought.

LS1 Edit has no control over the actual O2 heaters. The heater part is just 2 wires; 1 wire is 12 volts with the key on and the other wire is ground.

NoGo

iTrader: (2)

If the O2's are really generating that much of a problem, just get rid of them.

Keep your car in open loop.

It takes a couple sessions playing with the Fuel to Air Multiplier, but it works fine.

Gulph Emmissions vehicles, and other GM substituant vehicles around the world don't even have O2 sensors or Cats, and the run just fine.

Speartech

iTrader: (14)

I don't think he is to the point of going that extreme. O2 feedback is a good thing! If it's a street driven car, I would much rather deaden some of the diagnostics and keep it closed loop. If it's mainly a track car, then open loop is great; not much time for feedback anyway!

John

NoGo

iTrader: (2)

I am really surprised that more people just don't go open loop. It isn't that difficult to get a good running car that ignores the O2 sensors. If you mention it to most tuners though, it comes back as some sort of taboo. The taboo comes from people that kick the car to open loop and don't properly tune it, and it runs like CRAP!

Anyhoo, just my .02

Good Luck,
Kevin

felton316

What kind of headers are you using? I had the same problem with my SLP's until I used some exhaust sealant on the collector-off road pipe joint.

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by felton316:
<strong>What kind of headers are you using? I had the same problem with my SLP's until I used some exhaust sealant on the collector-off road pipe joint.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Grottyohann.......

So the sealant keeps heat in? What kind of sealant is it and where can I find some?

<small>[ December 08, 2002, 05:59 PM: Message edited by: verbs ]</small>

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Speartech:
<strong>I don't think he is to the point of going that extreme. O2 feedback is a good thing! If it's a street driven car, I would much rather deaden some of the diagnostics and keep it closed loop. If it's mainly a track car, then open loop is great; not much time for feedback anyway!

John</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The car is my daily driver, and makes about 1-2 track appearances per month.

So I'd prefer better daily driving characteristics...

felton316

I used some stuff called Silkolene, its about $20 a tube. I was told the reason that it was crapping out on me was due to a leak from the collector. I put this stuff on, then reattached the exhaust, cleared the codes from the computer. Haven't had the codes pop up since March. I too went through many new O2 sensors, until I started using this exhaust sealant.

Supposedly fresh air sneaking in the slip-on connections of the offroad pipes was reaking havoc with my O2's. No matter how hard I clamped it, it would still leak.

This stuff will go on with the consitancy of snot, but once it heats up, it'll seal. Any excess can wiped off.

<small>[ December 08, 2002, 09:25 PM: Message edited by: felton316 ]</small>

Team ZR-1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by verbs:
<strong>I'm on the verge of using header wrap as a last resort to keep my o2 sensors heated up enough to stop me from getting heater codes, which in turn cause the o2's to insufficiently switch.

Is there a way to wire my car so that the o2 sensors get more power allowing them to maintain proper operating temperature, or is there a way for ls1 edit to do this?

Anyone?

I really don't want to destroy my nicely coated headers with header wrap.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The PCM hardware is supplying the voltage for the heaters and thus also has to handle the current load of the heaters.
Also the hardware logic does compares and reason O2s have a return line and not a ground.
If you were to induce more current or resistance to heaters it would put too much load onto the PCMs total voltage load.

The heaters are only tasked to get the 02s to their minimum operating temp of 600 degrees, so
if your having problems it could be the 02s are not properly placed as to distance from the heads or there is an exhaust leak but then you also should see lean DTCs, esp if the leak is before the Cats.

If the 02 wires were cut/spliced it then would have disturbed the outside air source the 02s get via inside the wires as reference air and would cause ill effects.

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by felton316:
<strong>I was told the reason that it was crapping out on me was due to a leak from the collector. Supposedly fresh air sneaking in the slip-on connections of the offroad pipes was reaking havoc with my O2's. No matter how hard I clamped it, it would still leak.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I think my scenario is different. If fresh air was getting into my o2 sensors, they'd be ruined.

Just for testing purposes, it put all the malfunctioning o2 sensors on my Cavalier Z24 and they all work fine. So basically, while they are on my car they don't work. So fresh air isn't killing em off or else they wouldn't work on my other car.

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Team ZR-1:
<strong>so
if your having problems it could be the 02s are not properly placed as to distance from the heads or there is an exhaust leak but then you also should see lean DTCs, esp if the leak is before the Cats.

If the 02 wires were cut/spliced it then would have disturbed the outside air source the 02s get via inside the wires as reference air and would cause ill effects.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Well, I'm not getting any lean codes at all, and haven't during this dilemma. It could possibly be spliced wires, but I can't really find any. I still think its the placement of the o2's in relation to the heads, as other people have had this problem as well.

Team ZR-1

Being the 02 work fine in another car that says they are not the problem.
Being your not getting other types of 02 error codes ( unless someone turned the codes off in the PCM) it does not sound like a exhaust leak close to the 02s.

O2s must be mounted within the distance stock ones were else if mounted downstream it would be cooler and thus 02s would report incorrectly.

If the 02s were installed downstream and the stock wires were too short then someone would have either hacked the wires to make them longer or installed longer wires with more connectors.

Along with loosing the air reference flow of cut wires or using wrong type of wires, any splice would add resistance to the circuit and cause a lower output of 02s ( since 02s only output from 0 to 1 volt) to the input of the PCM for that compare circuit.

Return lines of 02s are not ground, thus if someone hacked on wires if they took returns to ground would confuse the compare logic of PCM hardware and 02 outputs would be skewed.

One other issue could be the pins on the PCM have been burned or corroded so I would check them and the 02 connectors and measure their resistance.

I've seen twice where knock sensors were suspect but it ended up it was connectors pins at fault.

<small>[ December 09, 2002, 07:19 PM: Message edited by: Team ZR-1 ]</small>

pedaltothemetal

If you want to place the front o2 sensors closer, you can have a muffler shop weld a new bung closer up. They all have the bungs in stock.

Leo

wrencher

iTrader: (2)

You don't have any o2 performance codes, just heater codes. Use edit to deactivate ses illumination on these codes, or chase the poor heater performance down. Does it set these codes on a cold start ? Done any amperage testing on heater circuits?

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by wrencher:
<strong>You don't have any o2 performance codes, just heater codes. Use edit to deactivate ses illumination on these codes, or chase the poor heater performance down. Does it set these codes on a cold start ? Done any amperage testing on heater circuits?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The problem is that with the heater codes come insufficient switching codes as well. When my car is throwing these codes, my L-Trims seem to lean out a lot more than they should. This may have an adverse effect at WOT since at part throttle my L-trims are as high as 14%.

C5 Tweaker

I looked at your location expecting to see you are in Canada or something - but you are in friggin Phoenix for God's sake. In 40 degree weather, my sensors go active in about 30-45 seconds with long tube headers. I doubt it is a heating issue.

It is more likely that you have a leak at the flange, bad air check valve(s), or leak(s) at the collector(s).

Was the other test vehicle OBDII? A non-OBDII vehicle may not be as sensitive to bad sensors.

As TeamZR1 indicated, a crimp or repair in the sensor signal wire can cause havoc as the sensor requires a minute air source through the wire strands for proper fresh air reference.

You really need to connect EFILive or AutoTap to this thing to see what is really going on. Are you getting errors on both sides? Any other codes, misfires, etc.?

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by C5 Tweaker:
<strong>Was the other test vehicle OBDII? A non-OBDII vehicle may not be as sensitive to bad sensors.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yeah the Cavalier Z24 is OBD II. I used autotap to see if there were any problems, but there were none.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by C5 Tweaker:
<strong>You really need to connect EFILive or AutoTap to this thing to see what is really going on. Are you getting errors on both sides? Any other codes, misfires, etc.?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I get errors on both sides. I even get a rare o2 heater code for one of my o2 simms <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> . That makes me think wiring right away since an exhaust leak won't make a difference on an o2 simm.

verbs

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by wrencher:
<strong>Does it set these codes on a cold start ? Done any amperage testing on heater circuits?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No amperage testing on heater circuits. The codes are being set in hot or cold weather, and not upon startup.

C5 Tweaker

Since you have AutoTap, what is the O2 voltage doing on a cold start? Do they both drop in voltage at about the same rate? How many seconds before they start switching (cold start, idle only)?

What are the minimum and maximum voltages do they achieve at cruise? What are the voltages near redline at WOT?

Have you driven the car for extended periods with AutoTap connected? You should be able to watch and get a good idea of what is going on.