Running WAY to rich

My car is running extremely rich. The wideband reads roughly 9.8 to 10.2 and I can see alittle black smoke as well as the car sputtering. This even occurs at idle. So far I have checked the sensors and they all seem to read just fine. Anyone have a solution? Maybe a spark plug not being responsive? I dunno? Car seemed to run just great before hand. This all of a sudden happened and Im up in the air as to what the problem could be.

 

[Andy_S]

Boost leak test?

 

I did one prior to this and after and found that the throttle body was leaking. I just had it rebuilt and installed it and still have this problem. This may be a stupid question, but what would a boost leak test tell me as far as running too rich (fuel)?

 

[Andy_S]

Metered air leaving the system. With a boost leak, the ecu thinks more air is going to the engine than there really is. That causes it to dump in more fuel for the air thats not there and that causes a rich situation.

 

[belize1334]

At idle the entire intake route is under vacuum so a leak will draw air in and cause a lean condition. If the leak is pre-turbo then it will continue to be a lean condition even under boost as pre-turbo will continue to be under vacuum. If it's post turbo it'll go rich under boost as metered air escapes. Either way, a boost leak doesn't explain a rich condition under idle. What does the narrow-band say? Is it cycling (closed loop) or just pegged high (open loop and rich)?

 

Thanks for the input. I will have to get another boost leak test since I did take off the throttle body to have it rebuilt. I guess I will just update as I go and wait for other feedback as well.

 

[jepherz]

Check your fuel trims. This will tell you if the ECU is trying to pull fuel to correct for whatever the problem is. Do you have an aftermarket AFPR? Is it set correctly?
Do you have new injectors? Maybe one is stuck open?
How old is your narrrowband o2 sensor?
You say there is black smoke, so I assume the car IS actually rich, otherwise I'd recommend re-calibrating your wideband too.

Have you done anything recently to warrant the car behaving differently?

 

My injectors are a yr old. The only thing I have changed recently before I had the throttle body rebuilt is I got rid of the stock IC setup and went to stainless; However, the problem didnt occur when I changed it till 2 months later. My o2 wideband is alittle over a year old, but maybe you're right, it may need recalibrating. /ubbthreads/images/graemlins/dunno.gif I will have to check again this weekend and follow through with you guys' advice. I figure also maybe its time to change my spark plugs too.

 

You don't say what you are tuning with. What injectors? MAS? How are you compensating? The stock openloop AFR is ~9.5:1.

 

[jepherz]

Yeah, he's saying it occurs (I assume 9:1 AFRs) at idle though.

 

[Terry Posten]

He is running EVO VIII injectors, 3G MAS, Keydiver chip, SAFC II, WB O2 (for tuning), 255 Walbro, SARD AFPR set to 38psi base, EIII turbo, middle sized FMIC and hard piping, and 3" turbo-back exhaust.

I need to do a leak test and adjust the TB since I just installed new seals.

Before the TB rebuild (just my poor attempt to help him out), the only leak was at the shaft seals and it was not that bad.

The chip came from someone from this site but I can't remember who. It came with the injectors but I guess it could be mismatched but it ran fine for almost 1.5 years. /ubbthreads/images/graemlins/dunno.gif

We use the SAFC II to dial it in on using the WB and knock lights in the dash.

My logger is dead and I no longer have the software to load on it.

 

[jepherz]

Terry, I don't think the logger software is still available, but I may have a copy somewhere. I can't remember if the model of palm matters. Do you want me to take a look?

 

[Terry Posten]

I would not mind getting my logger back together.

I have a palm 105.

I need to make sure I still have the CD for it to load on my laptop.

 

Thanks Terry for clarifying that for them.

 

Hey I would love a copy of that logger software. I had it on an old palm that is dead now, and can't find it anywhere.