A few months ago I got a cheap manifold and headers from the scrap yard and put them on my 1.6sohc. Catalytic converter in my car was plugged so it worked out, issue is the car has been running super lean. To the point where I burnt a hole in a valve so I'm in the midst of fixing that. Don't want this issue again so how would one go about making the car run richer? First o2 sensor is plugged in second one isn't, obviously check engine light is on so I want a work around. Cats aren't required where I live so I'd much rather avoid spending the $500 on a new one.

Any insight is appreciated, thanks!

 

Which 1.6 motor are you talking about? I believe there is 4 different 1.6 liter motors between 1992 and 2000, possibly more. Saying SOHC I think reduces it down to 3 typical ones.

I'm not sure if the Y7 has a cat in the header or not while the Y8 and Z6 I know the cat is under the car.

The under the car cats can be found for 100 bucks for a high flow one sometimes.

92-95 1.5 and 1.6L with teh exception of the USDM CX and any of the VX's:


Magnaflow brand 92-95 except the USDM CX and any VX:


Then for the 96-00 D16Y8 and maybe the Y7 if it's the under car cat:

 

I would check your pre and post o2 sensors with a dvm, and look particularly at the waveforms if its obd1. that will give you some insight on if the ecu is trying to lean out your air/fuel mixture or not, then you can kinda go from there. if its obd2, check out your fuel trim using a small handheld scanner (innova is a good brand), and go from there. before you do any of that though, you need to get that valve replaced, as well as a couple new o2 sensors. get your cylinder head removed, and take it to a reputable machine shop and have them resurface the head, and check everything else out, replacing valve stem seals also.

 

The main reason why valves burn is because they are not adjusted and become too tight. When a valve doesn't close all the way it overheats because it can't conduct heat away via the edge touching the seat.

 

I have the y7, I wish it was just that easy for me to get a new cat. I don't have my old manifold anymore, and I don't want to have to get a new one and pay to get that cat welded, etc.

I'll look into that, it's a slow process. Dropping the head off and ordering parts next week. Thanks for the input.

When I did a valve adjustment troubleshooting the misfire behfore I took the head off, the intake valves were tight as hell. Backed them off to factory specs and the car ran much better but still misfired. That's when I figured it was a bent valve or something. Didn't think it would have rusted as well

 

A DX / LX is readily converted to EX style exhaust. Use a header (or stock EX iron manifold and front pipe), EX inline under car cat, and cat-back parts as desired. You will have to extend the wiring to reach the oxygen sensors in their new location under the car, but you can buy extenders already made up.