A Nissan Sentra Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
45 Posts
Discussion Starter #1
Hey everyone, I need help/ suggestions. My car is running really rich right now so I want to fix this issue but theres no money for a tune. My brother suggested to put in a fuel pressure regulator and air/fuel ratio guage to fix the issue. Any suggestions on how I should approach this issue?
 

·
Registered
Joined
·
1,164 Posts
How rich is "really rich"? Specs run fairly rich straight out of the factory.
 

·
Registered
Joined
·
1,018 Posts
Throw on a wideband and make sure you are running rich.... or
Use a cell phone app or Scan tool to pull up fuel trims.

In either scenario, I'd start by look for vacuum leaks.

- - - Updated - - -

Also is this car modded?
 

·
Super Moderator
Joined
·
20,851 Posts
Put a catalytic convertor back on the car and you won't have that smell anymore. That's why there's a smell. Because you removed both cats

Stop listening to your brother, you don't need a fuel pressure regulator. However a wideband is never a bad idea ever. Isn't gonna fix anything, but good to have anyway. You'll install it and see your car is not idling rich. And that's worth something
 

·
Super Moderator
Joined
·
20,851 Posts
To reassure you. My car actually idles slightly lean. And it smells rich as fuck. Because I have no cats. I DO have a wideband.
 

·
Super Moderator
Joined
·
20,851 Posts

·
Registered
Joined
·
169 Posts
you need to 1. have someone AFR with a sniffer or 2. with a wideband.....specs run rich from the factory as it is so its not uncommon to smell unburned fuel as you have no cat since thats the cats job to burn off the unburned fuel
 

·
Super Moderator
Joined
·
20,851 Posts
you need to 1. have someone AFR with a sniffer or 2. with a wideband.....specs run rich from the factory as it is so its not uncommon to smell unburned fuel as you have no cat since thats the cats job to burn off the unburned fuel
But they don't idle rich. And they still smell rich at idle with no cat because no cat. The only reason he thinks the car is running rich is the smell. Unless he looks at his o2 data and fuel trims and sees something wrong, or looks at his spark plugs and see something wrong, or does what you said amd actually monitors his AFR, there's absolutely no reason to suspect the car is idling rich. He removed both cats. There's going to be a smell no matter what his air fuel ratio is.

The only apparent problem here is no cats. If you want to have no cat for a couple horsepower then you're gonna have to live with the smell that comes with that. Or install a cat on the midpipe again (what he calls a downpipe)
 

·
Super Moderator
Joined
·
20,851 Posts
I should clarify and simplify my point.

It doesn't smell rich. It smells like there isn't a catalytic convertor.
 

·
Registered
Joined
·
1,993 Posts
The O2 sensor could be worn out. The O2 sensor determines how rich the fuel is and sends the signal to ecu to adjust mixture.Test it.
 

·
Registered
Joined
·
1,993 Posts
Also clean the maf and make sure that your air filter is clean. Are you running at the normal operating temperature?
 
1 - 14 of 14 Posts
Top