DoubleV

I checked my plugs today and my car appears to be running a tad lean. It's also currently running a bit rough too ( for who knows what reason/reasons exactly ). So what can you do to fatten up a CCC carb? If I adjust the idle mixture screws/air bleed richer, all that will do is make my dwell lower and that's not where it should be so I'm not sure what I'm supposed to do.

I haven't detected any vac leaks although it seems to be running as if it has one.

On a possibly related note, I'm having a bit of trouble keeping my dwell at 50% according to my scanner. Perhaps this is due to my engine running a bit rough?. Everytime I get it close around 50% ( high 40's to low 50's ), the next time I check it, it seems to be more in the 58-60% range.

I'll be putting shorty headers on it soon too, which I assume would make it run even leaner still, so I would like to know how to fatten this thing up.

P.S. I'm assuming my high TPS voltage ( .60 when it's supposed to be .41 ) has nothing to do with this.

naf

iTrader: (7)

The ECM is going to do its best to maintain a stoich mixture and as long as you're getting a varying dwell you can assume the ECM is happy-at least for that one bank that contains the O2 sensor. There's a few things you can check:

Do the plugs look different between banks? Some vacuum leaks may affect one bank more than the other and the ECM is only reading the driver's side. A problem in the carb, or idle mixture screws not set identically could also result in different metering between sides.

Have you tried driving with the dwell meter connected? If the meter is pegging rich while driving, conditions are getting out of the narrow range in which the ccc-qjet can adjust to.

Some variation in dwell is normal. You may want to check your throttle bushings though. I've seen worn ones cause an intermittent, variable leak that would cause rough idling as the dwell fought to keep mixture. In that case they were bad enough to cause the throttle to occasionally hang.

TPS voltage at 0.60 should not be a problem.

DoubleV

Thanks for the quick response naf.

Yes I drive with my scanner hooked up and the dwell is definatly moving around. It's just that everytime I slow back down to idle, it seems to be at about 58% instead of the 'closer to 50%' setting I set it to.

Most of my plugs were good ( maybe a LITTLE on the lean side ), but my #1 cylinder was worse than the others ( and I think one other but can't recall which one though ). The motor is a fresh rebuild by a reputable place.

I will be tuning my carb and resetting everything to factory specs but I need to find all the CCC tools to do this properly and I just can't find them anywhere.

I think my throttle shaft bushings are good but I will check them again when I take the carb off.