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DISCUSSION => General Topics => Topic started by: GruntE30 on December 10, 2006, 12:02:08 PM

Title: Losing MPG...
Post by: GruntE30 on December 10, 2006, 12:02:08 PM

Sup guys, got a question for yous.  I do mostly freeway driving and was consistently getting 350 miles per tank using premium.  Now for the last 7 or 8 tanks I've dropped down to 300 miles per tank.  I know 300 miles is still good and people would kill to get that on their non e30s but its just bugging the hell out of me, especially with the gas prices.

Now It started around the time that I cleaned my ICV and ran seafoam through the vacuum line and added the rest in my tank.  I did this twice on 2 seperate tanks.  At first I thought maybe the seafoam was causing the fuel in my tank to burn faster or something so I let it go for the first 4 tanks but now I'm just like WTF?  Does anyone know of the seafoam damaging the 02 sensor or something?  Maybe thats why I'm running rich and getting the lower gas mileage?

Any help would be greatly appreciated!

Title: Losing MPG...
Post by: GruntE30 on December 10, 2006, 07:55:47 PM

Am I the only one with this problem?

Title: Losing MPG...
Post by: johna on December 11, 2006, 12:38:03 AM

I dropped from 9.x l/100km to 11.x l/100km when a workshop forgot to reconnect my O2 sensor after changing my clutch. So O2 sensor sounds like a possibility to me.

Title: Losing MPG...
Post by: Alpine003 on December 11, 2006, 12:14:22 PM

There's a possibility that your 02 sensor can be the cause but I've had a similiar experience with an older Acura and seafoam. My Acura got mid 20's before Seafoam and mid to upper teens after Seafoam. I suspected the removal of carbon made for a less "tight" motor reducing efficiency.

Title: Losing MPG...
Post by: sheepdog on December 12, 2006, 07:28:21 PM

May have caused buildup on the o2 sensor.

Title: Losing MPG...
Post by: GruntE30 on December 12, 2006, 08:14:20 PM

Thank you guys for the replies.  One other question, if it is a carbon buildup on the 02 sensor, can I clean it off with lets say carb cleaner?  Or is it pretty much done?  They are pretty expensive.

Title: Losing MPG...
Post by: nickmpower on December 12, 2006, 09:06:19 PM

there us a universial one you can get that will work

Title: Losing MPG...
Post by: Eurospec on December 12, 2006, 10:15:13 PM

Quote from: nickmpower;15503

there us a universial one you can get that will work

Could you provide some additional information?

Title: Losing MPG...
Post by: Alpine003 on December 13, 2006, 09:00:30 AM

Quote from: Eurospec;15505

Could you provide some additional information?

Bosch 4 wire universal. I'm running one now. The only difference between $75-$100 price difference is the factory plug on the end.

Title: Losing MPG...
Post by: GruntE30 on December 13, 2006, 07:38:31 PM

Thank you guys very much.