Burning too lean/rich

[Powerzen2002]

I smell a really foul odor coming from the exhaust, had the cat.
checked, no problem there.

Just replaced the muffler and connector pipe as well as a
new resonator. All in the past 3 months.

Gas: I use 89 octane
Plugs: Bosch Plat's +2's
Wires: AutoLite's (7.5 mm)


I tried changing the gas to 87 but still smells rich.

what should I do?

[BRB240]

If you are running rich then maybe your O2 sensor might not be working properly, so check it.

[Powerzen2002]

yea, already thought about that. only replaced it a month ago.

did a computer scan, running normal ... no error codes.

[BRB240]

Try a bottle of fuel system cleaner. Your injectors might be dirty. It could cause a bad spray pattern that doesn't burn well so you are getting a lot of unburned fuel exiting the cc so your exhaust is smelling like your car is running rich.

[EricP]

I have the exact same problem....i replaced O2 sensor and other things still runs too rich. I actually have problems starting the car too. any suggestions (not the battery)

[Zenki_S14]

i just realize my o2 sensor isn't hooked up to my injen intake. maybe that's why i keep having those backfires, and my car idles too. could that be the reason?

[95se]

I have the same problem. Replaced cat and have had it checked by 2 different mechanics and everything is right on the money. It started a year ago right after its 60K tuneup. The last mechanic asked if I drove hard, which I was like sometimes, and he said that the computer system tells it to go full rich at 3/4 throttle. Regardless, I don't think any car should have this smell no matter how you are driving. I smell it pretty much all the time regardless of how I drive it. Its a '95 with only 66K miles on it.

[91blk240]

i just realize my o2 sensor isn't hooked up to my injen intake. maybe that's why i keep having those backfires, and my car idles too. could that be the reason?

i assume you meant that your car idles bad like this.....i am pretty sure that if the o2 sensor isn't properly hooked up it will idle poorly.

[logo20]

I have the same problem with my 89 240. I tryed fuel cleaner and that didn't help at all. when the last time you change your air filter? I'd had a cone k&n filter for about 15k miles, and it doesnt look dirty. you can get the ignition timing checked to make sure it's not too advance. other than that if the problem bother you too much get the fuel pressure checked.

[logo20]

another thing I forgot. I think the spark plugs should be gapped at .043 or so. the smaller the gap the less air/fuel burned. according to the manual specification the spark plug gap should be 0.39-.044.

[sxtasy]

Originally posted by Zenki_S14
i just realize my o2 sensor isn't hooked up to my injen intake. maybe that's why i keep having those backfires, and my car idles too. could that be the reason?

I hope you O2 sensor isn't hooked into your injen intake. The O2 sensor is mounted in the exhaust........

[Zenki_S14]

there was a little metal piece that i forgot to hook up. it was originally in the stock airbox. but now, it's just hanging there. i didn't know what it was exactly.

[d240t2]

It is an intake air temperature sensor. Don't worry about it...it is just there for diagnostics anyways. The ECU does not use it for any sort of fuel calculations.

Dennis