moore_716

iTrader: (2)

First off I'm using my phone I'm not drunk. Car is basically stock. EBay intake more for looks than anything else. I realize I'm up against a wall with this engine so I realize for the most part all the simple cheap add ons pretty much *add on* nothing. I put a cms ss header on the car. Be buying I asked if I would get Any cel's. They said no. They lied. So I now have no cat. The downstream 02 sensor faced st. Up and was a super tight fit. 2 tight evidentally as it ripped the wires out of the sensor. This alone caused major issues but I think I fixed those. I replaced the sensor but I'm butt deep in snow with no garage so I just zip tied it in the engine bay till I could install it. Gas mileage dropped to 20 mpg and. And on any day 40 degrees on up the car seems to load up. I could clr it out but this passed week it wouldn't. So yesterday I replaced both sensors and installed an angle fitting downstream to keep the wires a little better out of harms way. I've been getting a p0304 misfire cyl. 4 ever since the header. I did a complete tuneup a month ago. Yesterday I pulled #4 plug and to my surprise it was lean.
The only thing I haven't checked is the compression and the injectors. Any thoughts would be great. I'm losing my patience with this thing. Today it's 37deg. Its not really loading up but I can hear the miss. It feels better but the car is so underpowered to begin with it's hard to tell. I'll clear any remaining codes at work Monday and see what happens. I had a 93 vx before and had no issues with the same mods.

B20VtecVillain

The header alone wouldn't be causing a misfire nor would the faulty O2 sensor. If your running lean, I would definately check out your fuel system. Having a bad or removed O2 will simply force the ecu to run open loop with its maximum fueling map. This will cause a rich condition which would most definately cause your low mpg problem but not a lean or misfire scenario. Are you sure the plugs themselves are good. Also, what type of plug are you using? platinum plugs have been known to cause issues for some users and I recommend an iridium or stock copper style plug over platinum to all customers.

moore_716

iTrader: (2)

I'm using E3's

Former User

Check whether #4 injector is spraying fuel.

moore_716

iTrader: (2)

If it ends up being an injector issue I will replace all of them. Car has 160,000 miles on it. What would be an upgrade in injectors. I'm not sure what other vehicle makes might swap in that have better flow and or atomization?

B20VtecVillain

If your running a stock ecu use OEM injectors or you will run into trouble.

moore_716

iTrader: (2)

Thanks to everyone who has offered help. I'm an old fart and hate being a newb. I have been waiting for the "search button" replies but never got one. Thx for all who have offered advice. Trust me the stupid questions will mist likely continue.

moore_716

iTrader: (2)

just an update misfire is still there after changing both sensors (as i was told here). I used the search key and found enough bad things about the E3 plugs that im gonna change them out before getting injectors. Love this Michigan weather. I dont have time to change them out till Saturday and its gonna be -13 degrees. So happy to have a garage thats stuffed full of so much crap a car will never fit inside.