'06 Chrysler 300 Limited Mileage problem
 

Hello everyone. I recently was driving the car and noticed that my my mileage dropped from 22-24 MPG to 12 MPG in the span of a week to ten days. I checked with a mechanic friend and he asked if any warning lights have appeared on the dash and none have and he suggested to do a tune up. never has been done to the car in 116,000 miles. Bought a set of Bosch Platinum 4's and replaced them, reset the dashboard computer to zero and last night wife came home and said MPG on the dash had gone to 7 MPG. What could be happening? I am not getting any warning lights. Could there still be a code that I need to get read internally on the computer? Any help in avoiding a trip to the dealer will be appreciated. Thanks in advance.

With that many miles on the car I would recommend you use some seafoam.
Basically what seafoam does is remove the carbon build up from the engine as well as clean the fuel injectors and lines

For an example:

I've used it on my 2004 Grand Cherokee.
When I first bought teh truck I was getting about 12MPG.
I kind of thought it was normal because it was a heave SUV. But after speaking with others I should have been getting much more than that.
SO I used the seafoam and seriously, my MPG jumped from 12 up to 19MPG. The truck ran so much smoother and I've noticed better acceleration as well.

So I said what the hell.....and I tried on my 2004 Gixxer.
This time I only put about 1/3 of the bottle in the gas tank and sure enough there was a noticeable improvement in throttle response, idle, and acceleration.

It's very easy to do

1) Let the car run until normal operating temp is reached
2)Using either brake boost hose or the hose that goes from the intake to the PCV valve pour SLOWLY 1/3 of the bottle into that hose
The engine will sound like it wants to shut off, but dont let it.
Just slowly let the suction suck the liquid

SHUT THE CAR OFF

3)After that, Pour 1/3 into the gas tank.

4) (do this only if you plan to change the oil afterwards)
Pour 1/3 (remaining of the can) into the crank case
Start the car and let it run for about 2 minutes then shut it off again

Let it sit for about 5 minutes.

Start the car and you'll probably notice some white smoke.
This is normal as that's teh carbon being burned off
Take a drive (mest if on the high way) and do some wide open throttle runs

If you've done step #4, proceed to getting yor oil changed.


If not, enjoy the extra MPG's and HP you're achieved.

Click the following link for more detained info

http://www.seafoamsales.com/how-to-u...treatment.html

the bosh plugs are a no no only use champion ones to start with
what engine size do u have?

If he has a limited, It's probably a 3.5L motor

Thanks for all the replies and Blackknight is right, it is a 3.5L.
Also since the car had about 85,000 miles, consumes a quart to two quarts of oil between oil changes (depending on what kind of driving is done). Went to the dealer and was handed a list which contained every vehicle Chrysler makes which basically said that all their models "may" consume oil after 75,000 miles. The so called "100,000 warranty" does not cover oil consumption. I wish they would advertise that when selling their brand. Started using Rotella 15w40 and Lucas every three oil changes and that keeps it under a half a quart between changes.
My daughter has a '07 Doge Caliber which we bought bvefore the oil problem and told her to sell it this year before the warranty expires She doesn't need that headache.
As far as the Bosch plugs go, I have used them on my '93 Chevy K2500 with no adverse problem before (recently went to E3's and get better mileage) and that vehicle has 225,000 miles and does not consume oil either (less than half a quart between changes with those miles). But being a Chrysler, that may make a difference. Taking it out on the interstate in a while to see what it does. Thanks again.