41 Primary oxygen sensor heater
Thread Starter
Registered!!
Joined: Dec 2011
Posts: 2
Likes: 0
Rep Power: 0 
41 Primary oxygen sensor heater
1994 Honda Civic EX. I pulled a code 41 so I proceeded to change out the o2 sensor and it still wouldn't start and pulled the same code. I discovered a green electrical fitting that was snapped off. It has a nut with a small thread that goes into ??. It's behind and just above the distributor cap. I'm assuming that it is the other end of the o2 sensor, hence the continued code 41. I need to know what it is called so I can go out and buy it. Where I can get one is appreciated.
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518 
Re: 41 Primary oxygen sensor heater
My pics are in B&W so I can't tell which one is green.
Really looks like the VTEC pressure switch. Wires would be blue/black, and black. Rearward from distributor. Won't cause a no start, but will spew oil all over if you leave it out. If you go to a dealer for the part, ask for their wiring diagram book for this car (the ETM). Flip through it, near the back are pictures. Pic #12 has a shot of it.
Or, print and take this with you: #16 switch, and #25 O-ring here: http://www.hondaautomotiveparts.com/...R+HEAD+%282%29
Code 41 is the O2 heater circuit. Heater should measure 10-40 ohms. Many aftermarket sensors are wrong. I always recommend OEM.
Really looks like the VTEC pressure switch. Wires would be blue/black, and black. Rearward from distributor. Won't cause a no start, but will spew oil all over if you leave it out. If you go to a dealer for the part, ask for their wiring diagram book for this car (the ETM). Flip through it, near the back are pictures. Pic #12 has a shot of it.
Or, print and take this with you: #16 switch, and #25 O-ring here: http://www.hondaautomotiveparts.com/...R+HEAD+%282%29
Code 41 is the O2 heater circuit. Heater should measure 10-40 ohms. Many aftermarket sensors are wrong. I always recommend OEM.
Thread Starter
Registered!!
Joined: Dec 2011
Posts: 2
Likes: 0
Rep Power: 0 Re: 41 Primary oxygen sensor heater
I took the broken sensor into ABC Auto Parts and they identified it as the oil pressure switch and quoted $79.99. I cried poverty and got a discount of $10 or so. I really only had $75 on me. I went home and put it in. Turned the car over and no start, crank, but no fire. I checked my codes again and the CEL was solid, no flash. I did some looking on-line and that means a potential ground problem. I went back out and checked all the grounds and there was a piece of wood logged in between the bare ground wire and the frame. I removed it, tried it again and she started. Not sure if that was it or just giving it a rest was it, but it runs great now that I've replaced the o2 sensor as well. Thanks for your help!
David
David
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518 Re: 41 Primary oxygen sensor heater
I took the broken sensor into ABC Auto Parts and they identified it as the oil pressure switch and quoted $79.99. I cried poverty and got a discount of $10 or so. I really only had $75 on me. I went home and put it in. Turned the car over and no start, crank, but no fire. I checked my codes again and the CEL was solid, no flash. I did some looking on-line and that means a potential ground problem. I went back out and checked all the grounds and there was a piece of wood logged in between the bare ground wire and the frame. I removed it, tried it again and she started. Not sure if that was it or just giving it a rest was it, but it runs great now that I've replaced the o2 sensor as well. Thanks for your help!
David
David
Almost any dealer can usually have parts ordered for next day delivery, if you order it early enough. Our cutoff time is 3PM for next day delivery.
Glad it's running though. Good job.
Thread
Thread Starter
Honda Civic Forum
Replies
Last Post
BootyDo
7th Generation Civic 2001 - 2005
8
Jun 21, 2016 03:45 PM
mistermenphis22
Mechanical Problems/Vehicle Issues and Fix-it Forum
13
Jul 13, 2015 04:43 PM
CivicsClass101
1st - 5th Generation Civic 1973 - 1995
0
Jul 9, 2015 11:14 AM
