Big problem after o2 change
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From: Owasso,Ok/Honolulu, HI
Big problem after o2 change Ok, I changed my right front O2 today and now something is really fucked up. Car idles at maybe 800rpm and when you give it gas, it does nothing until past half throttle. Plus when it is at cruising rpm, the whole car shakes and feels like the motor wants to fall out. The exhaust smell is almost overwhelming as well. Is it just running ungodly rich/lean or could it be more serious. Oh, and it runs just fine when the SES light is on.
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From: Owasso,Ok/Honolulu, HI
I think it is a Bosch. Whatever they sell at autozone, don't have the box with me at the moment. I want to get it scanned but won't be able to until tuesday next week.
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From: Decatur, TN (N-W of Athens)
Everyone says the Bosch suck, but for me which is a single wire, $18/ea I just couldn't pass up. Delco is what everyone here swears by for the O2s.
Make sure the wire/s didn't melt on the exhaust, or it's plugged in right.
Make sure the wire/s didn't melt on the exhaust, or it's plugged in right.
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From: Owasso,Ok/Honolulu, HI
well, I was able to get it scanned today and the codes were 43-Knock sensor and then one was for the electronic spark control. Not sure what that is. Though I see no reason an o2 would affect it.
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Verdad Gallardo code 43 is the knock sensor. That's a fairly serious code, basically the computer will pull a really high amount of timing and you will lose a lot of power. It's usually either a bad knock sensor or bad wiring/connection to it. You can do the diagnostic on shoebox's site to find out which it is.
Not sure how you can think the o2 would not affect it if you only noticed this behavior after changing the O2s. It's been proven over and over that the bosch o2s do not work well in these cars.
Not sure how you can think the o2 would not affect it if you only noticed this behavior after changing the O2s. It's been proven over and over that the bosch o2s do not work well in these cars.
I ran with new Bosch O2s since I built my 383. The car ran filthy rich at everything except WOT. I just finally changed to new AC Delcos and have notice a major improvement. I'd only use the AC Delcos from now on.
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From: Owasso,Ok/Honolulu, HI
Originally Posted by infinitebird
Not sure how you can think the o2 would not affect it if you only noticed this behavior after changing the O2s. It's been proven over and over that the bosch o2s do not work well in these cars.
Change the o2 before you mess with the knock sensor. The KS is stuck in there good anyhow. It could be working properly and pulling timing because the crappy o2's are showing a lean condition.
Originally Posted by Ralls
Change the o2 before you mess with the knock sensor. The KS is stuck in there good anyhow. It could be working properly and pulling timing because the crappy o2's are showing a lean condition.
Originally Posted by lookin4aTA
So no one has any idea?
Originally Posted by infinitebird
no, code 43 means there is an electrical fault in the KS circuit. Basically the computer can not get the correct signal from it. It wouldn't have anything to do with the O2s. What you're describing could occur but the knock sensor would still have to be working correctly to provide a signal to the computer. code 43 means it's not.
One thing to look for is how your plug wires are routed. It is possible for the KS to see incorrect reading by induction from a spark plug wire if rapped around it.
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From: Owasso,Ok/Honolulu, HI
Originally Posted by infinitebird
no, code 43 means there is an electrical fault in the KS circuit. Basically the computer can not get the correct signal from it. It wouldn't have anything to do with the O2s. What you're describing could occur but the knock sensor would still have to be working correctly to provide a signal to the computer. code 43 means it's not.
LT1falcon-you aren't the first to get confused by that. I have even done it myself when not paying attention lol.
It could be the knock sensor or the pcm/wiring. You need to do the resistance test to find out which.
See here: http://shbox.com/1/4th_gen_tech2.html#knock_sensor
See here: http://shbox.com/1/4th_gen_tech2.html#knock_sensor
Originally Posted by lookin4aTA
What do the ports look like on the PCM? Never done one of these before.
On The Tree
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From: Smithfield, VA
I believe that the pass side O2 wiring and the knock sensor wire run down from the pcm together on that side of the engine. It is possible that you did someting to the knock sensor wire while you were trying to get the O2 out.