O2's and Fouled Plugs?
Thread Starter
TECH Apprentice
Joined: Jun 2002
Posts: 319
Likes: 0
From: NH
O2's and Fouled Plugs? I guess I am having the same problem as Jeromio. My car has run fine open exhaust for the past week(no driven). I finished up the exhaust and installed the O2 sensors and the engine ran like **** when warm. Since then I have been only able to get it to fire on maybe 1 or 2 cylinders before dying. I pulled the plugs last night and they are black. I will be replacing them tonight. What is to keep them from fouling again. I have no diagnostic tools yet. This will be the first time starting the car with the exhaust and coolant systems in complete working order so maybe if I perform the PCM idle learn procedure completely everything will be okay. What do you guys do for the idle learn procedure?
Teching In
Joined: Oct 2002
Posts: 28
Likes: 0
From: Austin, Texas
Re: O2's and Fouled Plugs? I had the same problem. A friend of mine who runs the repair shop for a large Chev dealer brought his testing equipment by the house and we discovered that I had misswired two of the O2 wires. My son-in-law built my wiring harness and those were the only two mistakes so I was happy.
Thread Starter
TECH Apprentice
Joined: Jun 2002
Posts: 319
Likes: 0
From: NH
Re: O2's and Fouled Plugs? It is officially time for me to take a break from this project. Yeah my plugs were carboned up, so I put new .99 cent plugs in to see what is happening. Still didn't start. Noticed the inline pump sounded louder. Checked the fuel rail...AIR!!!! No gas in the tank. Put gas in fired right up. 
You would be suprised how much easier it is to start an engine with gas.
You would be suprised how much easier it is to start an engine with gas. 
Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: O2's and Fouled Plugs? Yes, I have the exact same problem. Haven't had time to do much with it since Sunday. I put $2 plugs in mine 
. I guarantee they'll get fouled again until the close loop issue is sorted. I am hoping in my case that I have an exhaust leak and fixing that will take care of the problem.
I'll also be swapping out the O2s for the other set I have. I don't suspect wiring since I am using a stock FBody harness - the only mods were to cut off the trans stuff (A4 harness, T56 car).
BTW, I also ran mine out of gas. Was able to figure it out pretty quickly though, so, not toooo embarrassing. My stupid brand new Autometer gauge reads 1/2 full on an empty tank?!? FBody sending unit should work perfectly, so I think I musta got a bad gauge.
. I guarantee they'll get fouled again until the close loop issue is sorted. I am hoping in my case that I have an exhaust leak and fixing that will take care of the problem.I'll also be swapping out the O2s for the other set I have. I don't suspect wiring since I am using a stock FBody harness - the only mods were to cut off the trans stuff (A4 harness, T56 car).
BTW, I also ran mine out of gas. Was able to figure it out pretty quickly though, so, not toooo embarrassing. My stupid brand new Autometer gauge reads 1/2 full on an empty tank?!? FBody sending unit should work perfectly, so I think I musta got a bad gauge.
Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: O2's and Fouled Plugs? Have you solved this problem yet? I've been driving the car with O2s unplugged. I swapped out the pass. side sensor and I fixed an exhaust leak, but it still ran like crap in closed loop. I still have yet to inspect the driver's side O2 sensor.
Basically, I'm still in the dark and I'm looking for someone else to solve my problem for me
Basically, I'm still in the dark and I'm looking for someone else to solve my problem for me
Thread Starter
TECH Apprentice
Joined: Jun 2002
Posts: 319
Likes: 0
From: NH
Re: O2's and Fouled Plugs? I do not think I have a problem. I have not checked my plugs since I replaced them, but I did run the car up to 235 degrees to test the fan circuit and it ran fine. I have not logged any road time yet, but I hope to this weekend. I will let you know if things should get worse. Make sure that you perform the Idle Learn Procedure before stabbing the throttle. When I didn't do this my car ran like ****.
Trending Topics
Thread Starter
TECH Apprentice
Joined: Jun 2002
Posts: 319
Likes: 0
From: NH
Re: O2's and Fouled Plugs? Manual says to get the water temp to 176 degrees and then let it idle for 5 minutes and then turn it off for 30 seconds. So, if it is cold it is going to have to sit and idle a long time to reach 176 and then 5 more minutes...all without touching the throttle. Doesn't say anything about ac.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
