Charger Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1 (Edited)
Hi guys. I'm new here so I hope I have this in the right place. I tried a couple other forums but no one ever answered my questions so I'm hoping all you guys are more knowledgeable and personable. I have a 2007 dodge Charger(base model) with the 3.5L high output motor in it. I've only owned the car for a few months but I bought it from my father-in-law after my old car was in an accident. He maintained the car like clockwork(always used the dealer though). It runs pretty good but I do have a couple weird issues. First issue is my gas mileage is crap. I live in North Carolina so most speeds here are 45-55mph no matter where I go(so highway'ish speed driving mostly). I have been tracking the gauge and I'm lucky if I get 200 miles to the tank. The best I ever got was 240 miles to a tank and that was babying the pedal everywhere. I haven't done any real work to it since I got it because everything SEEMS normal(no engine lights, codes, etc.) My father in law has his maintenance records in the car and a tune-up was done a few months before I bought it from him. Tranny fluid, engine oil, plugs, wires, etc. all changed. The only thing I notice is the car has a long crank before it starts all the time. If I turn the key to the run position and let the fuel pump finish priming first, then start the car, it starts on a dime. But that's the only way it will start normally. The second issue I have is a throttle hesitation when I push the gas peddle. It's as if the electronic throttle needs a second or two before it moves? I dunno, this is the first car I have ever owned that has this electronic throttle crap. And my last issue is whenever I go to start the car, I can hear my throttle body doing this crazy dance like the throttle plate is opening and slapping shut. It does it about 3-4 times in a row and then stops. Is this normal? Any advice you guys can give me will be greatly appreciated. Oh, I almost forgot, another issue is it drives great on some days while on other days it has a stumble in the engine and acts like it doesn't wanna drive.

EDIT: The car has 150K on it.
 

·
Registered
Joined
·
77 Posts
I had a 08 5.7 gave me similar problems spark plugs were worn out. Check and see what kind of plugs are in it and if their gap right. Maybe check the battery too. Not saying this is were your problem is but its a place to look.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #3 (Edited)
I had a 08 5.7 gave me similar problems spark plugs were worn out. Check and see what kind of plugs are in it and if their gap right. Maybe check the battery too. Not saying this is were your problem is but its a place to look.
I had the battery and alt checked, both checked out perfectly fine. The spark plugs? Yeah, I will give those a look because as I said, my father-in-law used the stealership for all his maintenance and I don't trust those lazy @@#$%;ers! I was thinking of changing them out with NGK's anyway cause my 2000 LHS with the same motor ran great with them. I have the stuff to give it an oil change but haven't done so yet cause I'm waiting for the weather to warm up more first. I'm also planning on changing out the tranny fluid and filter to be sure that was actually done too. I was told to replace the fuel pumps because the waiting to prime first and then get a normal start could be due to one or both of those failing.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #7
Your 3.5 is using a lot of gas because the 3.5 is very bad on gas.
How can that be considering I had the same engine in my old 2000 LHS and it ran amazing and was great on gas? Now I know this one will use more because the car is A, heavier and B, a rear wheel drive. If we do the math here, this car is rated at(take that with a grain of salt) 19mph city and 29mpg highway. so with a 18 gallon tank, I should be getting, on the low end, 270 miles to the tank. That's considering a combined estimate of 15mpg. I'm lucky if I can get 220 out of a full tank. And yes, I have done all the filling the tank to top it off, tracking how much fuel is in there, tracking miles driven, taken road conditions into account, etc. Most of our roads here where I live are all flat, some hilly terrain but not much around here. And that 220 miles to the tank is from topping it off where the pump shuts off to driving it till the light dings at me on the dash, plus counting a few extra miles for the reserve fuel still in there. I'm sorry but "Your 3.5 is using a lot of gas because the 3.5 is very bad on gas." answer just doesn't make par. There has to be something causing this much fuel to be used on a modern car that shouldn't use that much fuel. And it certainly isn't a heavy foot.
 

·
Registered
Joined
·
328 Posts
How can that be considering I had the same engine in my old 2000 LHS and it ran amazing and was great on gas? Now I know this one will use more because the car is A, heavier and B, a rear wheel drive. If we do the math here, this car is rated at(take that with a grain of salt) 19mph city and 29mpg highway. so with a 18 gallon tank, I should be getting, on the low end, 270 miles to the tank. That's considering a combined estimate of 15mpg. I'm lucky if I can get 220 out of a full tank. And yes, I have done all the filling the tank to top it off, tracking how much fuel is in there, tracking miles driven, taken road conditions into account, etc. Most of our roads here where I live are all flat, some hilly terrain but not much around here. And that 220 miles to the tank is from topping it off where the pump shuts off to driving it till the light dings at me on the dash, plus counting a few extra miles for the reserve fuel still in there. I'm sorry but "Your 3.5 is using a lot of gas because the 3.5 is very bad on gas." answer just doesn't make par. There has to be something causing this much fuel to be used on a modern car that shouldn't use that much fuel. And it certainly isn't a heavy foot.
My 2010 has never gotten the advertised mileage, ever. There are an endless amount of factors that will increase fuel consumption however in regards to a Charger equipped with a 3.5 you just pile on even more.

You're right you can probably spend a lot of time and money replacing this and that trying different gas etc to increase a couple mpg but it seems a total waste trying to chase efficiency in a 4200lb car that is also under powered for its weight.
 

·
Registered
Joined
·
380 Posts
If you said how many miles were on it I missed that.

Based on what you've said, the first thing I'd replace is the oxygen sensors. All of them. With OEM from the dealership. Too many times they get slow and won't throw a code. That would explain your slow start (the heaters aren't working as fast as they should) and throttle lag (they're not responding fast enough for the PCM to adjust) and bad gas mileage.

Sent from my moto z4 using Tapatalk
 

·
Registered
Joined
·
8 Posts
Discussion Starter #10 (Edited)
If you said how many miles were on it I missed that.

Based on what you've said, the first thing I'd replace is the oxygen sensors. All of them. With OEM from the dealership. Too many times they get slow and won't throw a code. That would explain your slow start (the heaters aren't working as fast as they should) and throttle lag (they're not responding fast enough for the PCM to adjust) and bad gas mileage.

Sent from my moto z4 using Tapatalk
Funny you should mention O2 sensors. I had to replace one about a week into getting the car. And sorry, I did forget to mention the mileage, it has 150K on it right now. I'll fix that in my OP so others know. On another note, is this car a Cali emissions car or no?

EDIT: Nope, it's standard federal emissions.
 
1 - 10 of 10 Posts
Top