Running rich?

[invain]

Almost everytime I seem to get into boost and let off, I'll get puffs of smoke a few seconds later. I've also noticed a little bit of a lag/hesitation when I step on it and when building low boost. I'll also randomly get smoke after letting off the gas, but it clears up after only a couple seconds. I'm pretty sure it's unburnt fuel, I've even had people follow right behind me when it smokes and there's no oil smell. Obviously the ECU is tuned, but it's never been taken to the shop and tweaked at all.

What would you guys suggest I try first? Should I get a wideband and start playing around with air/fuel?

[DanThaMan]

what color smoke? orange, green, white, blue, black??

[invain]

Seems to be grayish colored smoke.

I've also noticed the car backfire a few times when it's acting sluggish/bogging down a little.

[invain]

I'm also having a problem with the car hitting what feels exactly like a rev limiter at around 5500 rpms, if this is in anyway related to the car running rich. I need to go out and play around some more but I'm pretty sure it's right at 5500 rpms, usually when I'm in decent boost (7-8 psi). Doesn't matter what gear I'm in, once I get to a certain point it's like the car hits a wall.

[invain]

Bump

[invain]

Could fuel pressure have anything to do with this? I have a walbro installed but have never checked the stock fpr.

[mattblancarte]

I'll just go out on a limb and assume this is an sr20 you're talking about. Gray/black smoke after you let off the throttle and puffs of it during acceleration is fuel.

Get your car tuned. That will fix it.

[invain]

Ka-t.

How much would it cost to take it to a shop and have it re-tuned? The ECU is pretuned for the current setup. I'm almost positive the car is running rich, wouldn't it be cheaper for me to just adjust a/f myself?

[invain]

Any more advice guys? I'd really like to get this figurd out.

[mattblancarte]

I dunno if you have a programmable ECU, or what the deal is, but if you do you should have it dyno tuned. You can expect about 300-400 bucks in dyno time to have it running awesome.