I bought a POS civic dirt cheap a year ago and I've been (very) slowly fixing it. The wiring looks horrendous under the hood so I'm sure these are faulty wiring. The CELs it's throwing are:

21 - Vtec solenoid valve
41 - primary O2 sensor heater

**Pics, prepare yourself for the horror**


1. Merry Christmas Vtec solenoid?



2. Random plug


3


Thanks.

 

Trace the red vtec wire back to the ECU it should go here:


It's hard to tell in your second pic but if its two wire than its the reverse light switch,4 wire it might be the 02. Do you have an 02 hooked up at all? If so check this thread for both codes above
https://honda-tech.com/forums/hybrid-engine-swaps-18/%5Bfaq%5D-%22my-vtec-doesnt-work%22-1812135/

Picture 3 is the intake air temp sensor are you sure you don't have a code for that as well (code 10)?

 

Thanks HondaPartsHero. I got the vtec solenoid CEL cleared. I do not have code 10, just 41 now.

The wiring for the O2 sensor is really long. It starts from under the dizzy and goes to the (only) O2 sensor, at the end of the header. The wiring is horrible; it is SPEAKER WIRE!!! I'm redoing the wiring tomorrow, hopefully that's all it needed.

I noticed my reverse tail lights don't work and now know why

Two questions:
-Should I only have 1 O2 sensor? Autozone said I should have a precat and post. I only have pre.
-What do I wire the reverse lights to? There is no male counterpart for the plug. The genius probably cut it...

Worst car ever.

 

If its obd1 you should only have 1 o2 sensor.

 

Need to know, doing this tomorrow.