Cascade Crew

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

I've been battling an extreme rich cold start-up. Only happens when the car is first started after sitting for 8 or so more hours. Pegs my wideband at 10:1 and slowly climbs to about 13.5ish:1 until it reaches closed loop then jumps to 14.7-15:1 and stays there. I plugged in the laptop and all of the sensors were still reading what they normally do. I was thinking it might be bad injectors

Now on top of the rich cold start, it runs lean closed loop. Jumping around 15-16:1 hovering mostly around 15.6:1. I hadn't made any changes to the car or tune around the time this started happening. I haven't had a chance to look at the data yet but this seems like the o2 sensor might be dirty/shot skewing the feedback to the ecm. Anybody run into this? I haven't had any issues like this yet.

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

So I put most of a can of seafoam in the fuel and I'll run the last little bit down the intake tomorrow. I also got some MAF cleaner and I went ahead and bought an oxygen sensor since I don't know how old it is. Hopefully it all makes a difference.

Dewey316 · Posted: Fri Feb 17, 2012 7:29 pm Post subject:

I'm confused, when its warmed up, is it lean or is it stoich? You said both. How are you verifying the AFR, it could be that your sensor isn't warmed up when first start the car?

If you are scanning it, what is the BLM reading, is it making large adjustments to the fueling, or just minor ones?

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

It's currently super rich cold, and 15.5-16:1 lean warmed up. I haven't yet scanned it I have to find my aldl cable. The only indication I have is some hesitation on cruising and part throttle acceleration and consistent lean readings on my WB o2 gauge, I think it uses a bosch sensor.

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

Got the sensor installed. I can't tell if it made any improvement because the threads came out with the old one. I had to unplug the WB sensor and move it there for now. Now the ignition coil is sparking over to itself, hopefully some dielectric grease will fix that. I also found a fairly long list of things about the Firebird that piss me off. Hopefully I'll be able to get something else to drive after I start work. If I don't this car is going to be melted down and made into pots and pans.

Dewey316 · Posted: Sat Feb 18, 2012 7:37 pm Post subject:

If you are misfiring a cyl, it will read leaner than normal on your o2 sensor. If you spark is not solid, that might account for the lean closed loop readings.

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

I hope so. I need to have a new bung welded on as I am still using a single wire sensor and it's further downstream than I'd like. Tomorrow I'll mess with it. I found the aldl cable so I'll see what the computer is up to. If it was arcing before it got worse, because it now kills the engine about once every 30 seconds. Was an interesting ride home from the garage today.

I found out the reason I've been losing oil is the trick flow heads I got are longer than my valve covers are so they are making metal to metal contact, not allowing the gasket to seal.

Also, my driver side axle isn't being retained properly. I had to make spacers to make up for the difference in thickness on the ls1 brakes. It looks like I need to make a thicker spacer.

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

Well I got anxious and got some dielectric grease and put it on, and then I found an embarrassing mistake I made while putting the 700r4 in. The car runs much better. If I had the WB o2 in I'm sure the stupid mistake I fixed will have the AFR back to normal. It isn't surging at idle anymore like it pretty much always had been since getting this engine so it appears the cleaning and new sensor did help.

I don't know if my start-ups are still ridiculously rich but at least it drives pretty normal.

Now I need to fix the rear axle.

Alphius · Posted: Sat Feb 18, 2012 10:28 pm Post subject:

Come on man, you gotta tell us the embarrassing fix. Wink

chevymad · Posted: Sat Feb 18, 2012 10:41 pm Post subject:

Spark snapping at the coil.. plug wire in wrong place or not connected..

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

Thanks to Dewey for leading me to it. Who knows how long I would have overlooked the obvious.

Alphius · Posted: Sun Feb 19, 2012 12:28 am Post subject:

It happens to all of us. Very Happy

Good find. I'm glad it's running better now.

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

I'll be much happier when this isn't my driver anymore so I can get some stuff done. The drivetrain is more or less pretty good but the car feels too cobbled together. I've had to add in wiring so it seems like I have 6 wiring harnesses on top of each other...because I do. My expensive valve covers don't fit my expensive heads so they leak oil on everything. The trans cooling lines are flex lines. They are installed well but I still don't like it. The headers bang on the frame due to their...crappiness, and probably the crappy motor mounts. Exhaust is 2 different sizes...I could go on. The car is going to be 30 years old next year. I cannot really rationalize spending the time or money to fix all those things but I'm sure I will anyways because I'm irrational.

*Edited to include leaking valve covers. Not because it is important to know, but because it really pisses me off.

RSFreak · Posted: Wed Feb 22, 2012 9:26 am Post subject:

Don't feel bad, I ran on the dyno with only seven wires last year. Rolling Eyes