Questions about LT headers & O2 Sensors
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11 Second Club
Joined: Dec 2002
Posts: 169
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From: Millersville, Maryland
Questions about LT headers & O2 Sensors About 8 month and 2,000 miles after installing LT headers w/ cats I begin getting codes P0135 and P0155 (O2 Sensor heater circuit malfunctions). From searches I have learned that this is a very common problem. The cause, as I understand it, is that because the sensors are now located further from the block it takes longer for them to get up to proper operating temperature. But I’m not clear on the following:
Thanks.
- have the sensors actually gone bad or is the computer simply reporting that it is taking longer than expected for them to warm up (i.e., not a “real” problem?) I’ve read both versions. I’ve been told not to worry about it but I’ve also been told that the slow warm-up causes carbon build-up leading to sensor failure.
- is there any risk of damage to the engine? The car is running fine.
- what should I do? nothing? replace them?
- is this the reason some people replace their sensors with Corvette ones? If so, what is it that makes the Corvette ones work better than the stock ones?
Thanks.
As I understand it the vette O2s have a more powerful heater, that's why alot of people use them.
As for replace or not, considering all the problems O2s can cause, (lean/rich condition, rough idle, stalling, etc) I'd replace them, but that's just my thought
Something else you can think about, it's possible to eliminate the code with some ECM tuning (LS1 edit, HP tuners) they set the parameters so wide the code is never thrown, and you can monitor your fuel trims to see if the O2s are truely going bad (just another option)
As for replace or not, considering all the problems O2s can cause, (lean/rich condition, rough idle, stalling, etc) I'd replace them, but that's just my thought
Something else you can think about, it's possible to eliminate the code with some ECM tuning (LS1 edit, HP tuners) they set the parameters so wide the code is never thrown, and you can monitor your fuel trims to see if the O2s are truely going bad (just another option)
Originally Posted by Mr Ed
About 8 month and 2,000 miles after installing LT headers w/ cats I begin getting codes P0135 and P0155 (O2 Sensor heater circuit malfunctions). From searches I have learned that this is a very common problem. The cause, as I understand it, is that because the sensors are now located further from the block it takes longer for them to get up to proper operating temperature. But I’m not clear on the following:
Thanks.
- have the sensors actually gone bad or is the computer simply reporting that it is taking longer than expected for them to warm up (i.e., not a “real” problem?) I’ve read both versions. I’ve been told not to worry about it but I’ve also been told that the slow warm-up causes carbon build-up leading to sensor failure.
- is there any risk of damage to the engine? The car is running fine.
- what should I do? nothing? replace them?
- is this the reason some people replace their sensors with Corvette ones? If so, what is it that makes the Corvette ones work better than the stock ones?
Thanks.
I had the same problem. Code would come on and off on its own, no big deal but it started to bug me. Just get some better sensors in there
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Joined: Nov 2001
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From: Live Oak, FL - in the woods where the creatures lurk.
I get the P0135 about once a month. No data I've logged
indicates that the O2 is causing problems with fueling.
I just reset the MIL light with Autotap. If it gets to be
more frequent I'll probably go with the suggestions to
get a better O2.
FWIW, this is a fairly new GM replacement (stock) O2.
For some reason I never get a code for the other O2.
indicates that the O2 is causing problems with fueling.
I just reset the MIL light with Autotap. If it gets to be
more frequent I'll probably go with the suggestions to
get a better O2.
FWIW, this is a fairly new GM replacement (stock) O2.
For some reason I never get a code for the other O2.
