Brent 94

iTrader: (1)

I was racing my friend about a month ago and after the first run, everything was fine. Second run, my wideband was reading ErL (Error Low) which means it was rediculously rich. The car even sometimes idles with and AF ratio of 11.8!!! Then yesterday i was just driving the car because it's been in the garage for some time now and i did a 4th gear run to about 100 or so and afterwards, when slowing down in gear, i got the ErL message again. This time there was no change in engine sound, but the first time it happened the car was backfiring. I'm thinking that it is either and injector problem or an ignition problem. Hopefully nothing too serious. Think that it's a stuck open/leaking injector or is the car not firing? (maybe a bad coil or something) My mods are in my signature. Any information would be helpful.

Brent

Brent 94

iTrader: (1)

bump

rotoober

iTrader: (3)

What brand of wideband unit do you have? My innovative unit displays "O2" when slowing down from a high speed run. I still have the airpump installed and it is pumping the exhaust full of Oxygen. Are you still running the airpump? If not, I really don't know what happens to the a/f mixture when running down the engine like that.
You never stated if the engine seems to be running bad or has shown a loss of power, does it?

Brent 94

iTrader: (1)

The wideband i do beleive is a Uego Air/Fuel ratio meter, it looks just like this one I found on the internet http://www.racerpartswholesale.com/uego1000.htm I still have the airpump installed and working properly as far as i know. The airpump pumps into the cat so i don't see how that has anything to do with what the oxygen sensor is reading. The car backfired a few times when this first occured but this last time nothing was noticable, maybe the only thing that was different was that it did not seem to be slowing down much in gear like it normally does (but the rpms were up high so thats probably why that happened) As for the loss of power, i don't think it does. Still feels fast as hell to me. Still can't get traction in 1st or 2nd. Hope that gives you the info you were looking for.

rotoober

iTrader: (3)

With the engine running down the airpump (i believe) will continue to pump air into the exhaust system and purge out the system of your exhaust gases. You should be reading lean when you let off the throttle. I'll look at my gauge after lunch and see what it reads at idle, but I think it is also rich. Do you ever have problems with the car flooding, and having difficulty starting?

Brent 94

iTrader: (1)

the car never starts on the first turn of the key. I've figured it out though, i turn the key and crank the motor one time and then turn the key to all the way off and then it will fire right up. Never any problems when warm only when cold. The car goes extreme rich when i let off, not lean. 10.0 is rich and 15.0 would be lean correct? so error low would be way rich. Any problems with running extreme rich when letting off?

BMike

You sure it doesn't mean ERROR LEAN? Typically during decel you should see lean, and misfires will cause a lean mixture reading. This intuitively doesn't make sense, but you must remember a wide band ONLY measures the oxygen content of the exhaust. During a misfire the oxygen is not burned with the fuel, so there is lots of oxygen in the exhaust, and it should read lean. On decel the injectors should shut off causing the engine not to fire and again leave free oxygen in the exhaust. My car always displays LEAN when you decelerate. I'd say you should look for the source of your misfire, and not worry about the decel conditions.

KMAR

Don't know much about Air/Fuel stuff but, take off you oil cap and smell, if you smell gas you may have a leaky injector. Same thing happened to me, always smelt pretty rich until I had the rebuild and the injectors checked. The one leaking wasn't worth saving so I replaced all. Also, there is actually two spots the air pump pumps air into the exhaust tract, one is before the O2 sensor. That is why at this moment my car is running crappy at idle, the air pump is not running. The O2 usually sees this extra air and of couse the computer blah blah,.......... and I have a high flow cat, so that air pump path is plugged, which leads me to say, maybe your cat is plugged?? Not sure. Probably a good idea to change it out anyways. Also, my car backfires pretty good on decel, sometimes pretty violently, check the dashpot, its a damper that holds the throttle plates open a little bit to purge more air into the exhaust causing the O2 to read a little lean for a sec. If the throttle plates shut fast you get more back fires because the air does not have a chance to push all that fuel out. Not too sure, this may cause a rich condition??? Not too sure. Check it out.

Brent 94

iTrader: (1)

I don't know if it means lean or rich but instead of ErL when the mix is low,(rich) it will say ErH when the mix goes high, like if i turn the key to the on position the gauge will start at like 14.5 and rise until it hits ErH. If i start the car with it on ErH it backfires big time and starts. Usually i won't start it with it on ErH. Is it normal for it to rise up when i turn the power on the car on so that all the gauges come on with the car off.

rotoober

iTrader: (3)

ok, when my car is idling, it runs lean, about 18.0. On deceleration same thing, sometimes offscale lean. You may be right about the leaking injector, my gauge does not change when I turn the key on and don't start the car, if the car has been sitting overnight, it reads a constant 20.8 or so until I fire it up. I wonder if it could be something with your ems?

BMike

If it goes to ErH free air that should be "lean" mine does the same thing, starts at 14.7 and then rises to 20:1 and then just displays AIR. So you definately have an over fueling problem on decel and when you had that nasty miss. So I retract my previous comment, leaky injector sounds plausible, though I'd think it'd be an issue all the time?