[solar365]

Yeah, it appears from everybody else's comments that RT's experiences of major drops in fuel economy are a statistical outlier.

 

[RacingTiger03]

yes.. it appears so. A partially fouled injector with 35K on the clock? seriously? . I honestly wouldn't have even thought of it. Makes sense though.. and seems a LOT more plausible than a major valve cleaning from this little extravaganza. But it's not like I just putz around in this thing either, why would it have a partially fouled injector already? Heck My other car is still running OEM Injectors at 130K at 105% duty cycle at WOT, and they're doing just fine I honestly never even question injector integrity at the age of this car... Maybe I should?

 

[jon2002]

Probably due to bad gas...are you regularly pumping non-top tier fuels?

 

[bdc101]

Guys, this is not a heavy dose of the fuel system cleaner. When you take your car in for a "fuel system service," the technician unhooks the fuel line, and then hooks compressed air up to a bottle of exactly the same stuff you just put in your tank, and "pumps" it to the fuel rail (or in this case, the high pressure fuel pump) using the compressed air. Then they let your car idle in the shop until it runs out of fuel, and that's all they charge you $150 to do.

It's not even a "Mazda" brand fuel system cleaner, they usually just use commercially available products even at dealerships.

 

[RacingTiger03]

Probably due to bad gas...are you regularly pumping non-top tier fuels?

pumping the same stuff I put in the "other" cars... BP/pilot/loves. The only difference is regular vs premium. Even then, shouldn't the fuel filter take care of anything that would potentially clog an injector this early in life?


Honestly performance is significantly better than it's been for quite some time. That same on-ramp I always have brought up isn't giving me any trouble at all (I can hit 85 by the end of it with a bit of ease now vs before.)

 

[solar365]

Does the 6 have a real fuel filter? My Miata didn't.


It may have been something freakish, or it may be something isn't quite right with one or more of your injectors. If it starts to crap up over the next 10-20k you may need to replace the injectors.


I'd at least notify the service department of your local mazda dealers to put it in your records that you had injector clogging issues.

 

[beskhu3epnm]

I went from 33mpg (12/2013) to 26mpg (12/2014), and it's warmer weather this year than last. In fact, in order to achieve the 26mpg, I had to drive 8mph slower than I normally do.

In the meantime, I've observed the vehicle follows ruts in the road like there's no tomorrow.

It also feels like I'm riding on 4 unicycles for tires... almost like the wheels are loose (they are not). I have to assume the bushings are shot, and the wheels are experiencing some deflection at speed/load. The tires have started to wear unevenly as well. No pull to either side, just odd behavior over all surfaces.

Check your plastic undertray for anomalies as well... Most definitely these things are warranty issues. I would provide you an update, but I just unloaded the car on something else.

 

[RacingTiger03]

thanks solar. I'll mention it. They're a really good bunch, so I know if I brought it up they would take care of it. As I mentioned though, I really didn't want to take the car in because "MPG is bad now!". I think even they would laugh me out of the garage for that one, lol. So I wanted to try a few things first to confirm . This definitely has. I'm at 34MPG 200 miles into this tank now holding steady. That's normal for this time of year for me.

As for the fuel filter... I don't know? That's a thought for sure.. if the answer is no I may be looking into that route.




Besh, I checked the aero panels first as ticker recommended early in the thread, all good under the car. How many miles did your 6 have? I went through a period of REALLY REALLY weird steering feel at about 25K and it sorted out by 30K and the car feels good again. Also I'm due for a set of tires at 36K (buying next week in fact), and that certainly contributes some to those factors.


As for 36K.. turned to my wife this morning at 35914... "Anything you want me to get checked? Last chance on bumper to bumper, LOL"


Honestly.. with bumper to bumper toast, and a few random misc issues here and there that never really got 100% solved (rear seals sticking again, trunk still sticks, MPG taking a dump and being cured, steering felt wavy earlier and resolved itself with a few thousand miles, wind noise is still as annoying as ever with all procedures applied to all 4 doors).. I'm going to be looking hard for a nice low mile CX-7, or something similiar. I'm trying my best not to, as paying this car off is fast approaching, and I could get another really nice toy if I just suck it up. But I don't wanna... LOL.

Who would've thought performance wouldn't be on that list? hah. She feels great right now though, even has *decent* passing power at 2,500RPM now *shrug*

 

[beskhu3epnm]

Besh, I checked the aero panels first as ticker recommended early in the thread, all good under the car. How many miles did your 6 have? I went through a period of REALLY REALLY weird steering feel at about 25K and it sorted out by 30K and the car feels good again. Also I'm due for a set of tires at 36K (buying next week in fact), and that certainly contributes some to those factors.

The vehicle had 22,000 of the hardest miles you could ever put a vehicle through. Here in Canada, frost heaving destroys roads, cold snaps muddy the engines, sand and salt corrode and cause cancer. I had driven through snow deep enough for the front lip to form a snowplow... on a regular basis it seems. They dump enough sand and salt on the roads to make it a gravel texture. And everyone still crashes (for some reason).

The paint on the front of the vehicle looked like a shuttle going through re-entry. The paint on the rocker panels had worn down to bare metal. The various potholes (sometimes the road is the pothole) had deformed the tires slightly (and likely the 19" wheels). No wonder the bushings were shot. The body was flexing like a young Arnold Schwarzenegger and creaking like an old mattress at a brothel.

A good road here is one that doesn't smash your head off the side window on a regular basis. I exaggerate, but you get the idea.

That being said, I will say that this is the most fragile vehicle I've owned in a long time. When I first had it, I wouldn't have guessed it. Solid as an anvil, and a great ride to boot. The deterioration was quite shocking. The 2003 Nissan Maxima I had before this seemed to be twice as hardy, despite looking like it was made of tin (front control arm bushings and sway bar bushings through 3 hard years... nothing more).

I had a huge list of unresolved problems (axles, brake rotors, wind noise, engine startup noise, bushings, strut noises, clunks and bangs, trunk latch busted, throttle issues, power loss, horrible fuel mileage, seat heaters not working - the list goes on), partially due to the dealership... "car feels fine, nothing wrong" and due to the fact I live a ways away and had a hard time continually hassling them (better things to do).

An all time high of about 39mpg with ease to struggling to get 26 and no immediate recourse?

It was a relief to unload this one, sorry forum!!

 

[jon2002]

pumping the same stuff I put in the "other" cars... BP/pilot/loves. The only difference is regular vs premium. Even then, shouldn't the fuel filter take care of anything that would potentially clog an injector this early in life?


Honestly performance is significantly better than it's been for quite some time. That same on-ramp I always have brought up isn't giving me any trouble at all (I can hit 85 by the end of it with a bit of ease now vs before.)

From my own experience, direct injected engines are much more sensitive to (bad) quality fuels vs. fuel injection. I notice my fuel economy drops in my Mazda more dramatically vs my other (fuel injected) vehicles.


If you had experience a big jump in performance/mpg from one bottle of chevron, you probably would still benefit from a 2nd bottle.


Remember Chevron techron additive is a concentrated detergent, the same detergent that's used in Chevron pump fuel (which is a top tier gas). Non top tier fuels also have detergents, but to a much lower government minimum standard.

 

[jon2002]

The vehicle had 22,000 of the hardest miles you could ever put a vehicle through. Here in Canada, frost heaving destroys roads, cold snaps muddy the engines, sand and salt corrode and cause cancer. I had driven through snow deep enough for the front lip to form a snowplow... on a regular basis it seems. They dump enough sand and salt on the roads to make it a gravel texture. And everyone still crashes (for some reason).

The paint on the front of the vehicle looked like a shuttle going through re-entry. The paint on the rocker panels had worn down to bare metal. The various potholes (sometimes the road is the pothole) had deformed the tires slightly (and likely the 19" wheels). No wonder the bushings were shot. The body was flexing like a young Arnold Schwarzenegger and creaking like an old mattress at a brothel.

A good road here is one that doesn't smash your head off the side window on a regular basis. I exaggerate, but you get the idea.

That being said, I will say that this is the most fragile vehicle I've owned in a long time. When I first had it, I wouldn't have guessed it. Solid as an anvil, and a great ride to boot. The deterioration was quite shocking. The 2003 Nissan Maxima I had before this seemed to be twice as hardy, despite looking like it was made of tin (front control arm bushings and sway bar bushings through 3 hard years... nothing more).

I had a huge list of unresolved problems (axles, brake rotors, wind noise, engine startup noise, bushings, strut noises, clunks and bangs, trunk latch busted, throttle issues, power loss, horrible fuel mileage, seat heaters not working - the list goes on), partially due to the dealership... "car feels fine, nothing wrong" and due to the fact I live a ways away and had a hard time continually hassling them (better things to do).

An all time high of about 39mpg with ease to struggling to get 26 and no immediate recourse?

It was a relief to unload this one, sorry forum!!

Sorry to hear! How was the resell value? What did you replace her with? I'd love to replace my mazda, but I do not think it's worth anything near what I paid.

 

[RacingTiger03]

I had a huge list of unresolved problems (axles, brake rotors, wind noise, engine startup noise, bushings, strut noises, clunks and bangs, trunk latch busted, throttle issues, power loss, horrible fuel mileage, seat heaters not working - the list goes on), partially due to the dealership... "car feels fine, nothing wrong" and due to the fact I live a ways away and had a hard time continually hassling them (better things to do).

An all time high of about 39mpg with ease to struggling to get 26 and no immediate recourse?

It was a relief to unload this one, sorry forum!!

That sounds terribly familiar.. unfortunately so. I mean, I'm glad the techron additive resolved my MPG and power issue, but to have so much of it so soon?

The CX7 we owned before is a more fair example I can give. I put ~50K miles on it from 24K-75K when we sold it. Direct injected turbo, and was practically 21MPG the entire time we owned it (2 years) *shrug*. Note there that in the same 2 years I put MORE miles on it, and had no problems AT ALL. Again using primarily BP and pilot fuels in it. (love's is pretty new to my area, lol)

 

[tickerguy]

I've got almost 23,000 miles on my "6" since March (of this year!) and outside of a couple of small dings in the paint (mainly on the plastics in the front, not on the metal itself) consistent with various minor road debris it runs, rides and looks like it did the day I got it. Brake and tire wear are right "up the middle."

IMHO the "6" is an incredible road car. I've had a lot of vehicles over my years and in terms of overall driving experience for long periods of time behind the wheel I've not owned anything else I'd prefer. There are many faster and more-complex vehicles to choose from but in terms of the total driving experience it's a matter of balance -- IMHO Mazda has done a great job in that regard.

 

[solar365]

Racing Tiger, If I was in your shoes I would, despite your other cars never having problem with Pilot and BP gas, still make a new habit of filling up at a different subset of gas stations for the Mazda 6. If the problem happens again you will be able to completely rule out the brand/type of gas causing the problem.

Also, you should try "racing" your wife in the miata while on 93 octane again, perhaps you would be able to keep up now that your injectors are clean?

 

[RacingTiger03]

Racing Tiger, If I was in your shoes I would, despite your other cars never having problem with Pilot and BP gas, still make a new habit of filling up at a different subset of gas stations for the Mazda 6. If the problem happens again you will be able to completely rule out the brand/type of gas causing the problem.

Also, you should try "racing" your wife in the miata while on 93 octane again, perhaps you would be able to keep up now that your injectors are clean?

That I don't have much doubt about solar. 93, clean injectors, and this cold cold air right now, the 6 is rather peppy. It will still lose, but nothing as bad as the first time playing around. the on ramp where 80 was a struggle is now 85 with all of us in the car and a breeze with just me. Not the 120+ the formy cracks off, but pretty good for a daily family hauler. lol

 

[oc cc]

Hey guys, I too have horrible mileage. My car is at 25k miles. First 10k miles I'd average like 29 mpg. Now it's down to 23 and only going lower. I dropped it off at the dealer yesterday for a rough idle and bad mileage, hoping to get the injectors, MAF etc looked at. Will report back once I get the car.

 

[solar365]

Hey guys, I too have horrible mileage. My car is at 25k miles. First 10k miles I'd average like 29 mpg. Now it's down to 23 and only going lower. I dropped it off at the dealer yesterday for a rough idle and bad mileage, hoping to get the injectors, MAF etc looked at. Will report back once I get the car.

See if they can peek at the tops of the intake valves too! Everybody is wondering how this DI engine does for intake valve deposits...mazda says the intake valve timing keep it clean, but...

 

[ExB5]

Hey guys, I too have horrible mileage. My car is at 25k miles. First 10k miles I'd average like 29 mpg. Now it's down to 23 and only going lower. I dropped it off at the dealer yesterday for a rough idle and bad mileage, hoping to get the injectors, MAF etc looked at. Will report back once I get the car.

Hmmm..25k with rough idling, bad mileage. Interesting .I'm eager to hear from you as well, post dealer fix. I assume your air intake is still stock, yes?

Btw, I just hit 16k yesterday..nearing halfway, for another Techron FI dose. Still running on premium...

 

[oc cc]

Hey everyone, got the car back today.

They fixed my door insulation (thank God, the car was WAY too loud), but no luck on finding the cause of my bad MPGs. They checked MAF, filters, injectors, etc. They even said injector cleaning at 30k is part of their maintenance plan.

On the upside, Andy is the Master tech at Tustin Mazda, and he is the most awesome tech from a dealer I have ever talked too. Per my personal request, he took the car in the back and gave me all the diagnostic print outs to see if anything came up. Nothing did, but still nice of him to do so.

Other than that, I guess I will be going the fuel additive route to see if that helps as it did in your case.

Other than that, the only thing I can report is that I am due for tires and I am going with Michelin Pilot Super Sports. I will do some canyon carving and report back. Soon, I am planning on adding a swaybar and upgrading to EBC pads and rotors, and also adding in a drop in filter. Nothing major to the car after that. MAYBE some auto.exe stuff, but without Torsional-Stiffness here to answer my questions I am holding off!

 

[cpnfantstk]

Went on a trip last weekend from Orlando to Miami doing 75 to 80 mph the whole way . I got 33mpg going and 32 mpg coming back. I guess that's ok but was expecting a bit more. The car is a blast on the highway with good power but the wind noise is absolutely horrid. Btw..I used my usual Shell 87 going down and Mobil 87(couldn't find a Shell )coming back. No difference really in mpg.