Drive a 2004 Ford F150 4.6L V8 EXT CAB. It has 71,000 miles on it. Truck runs great, doesn't stall or miss and idles good but my gas mileage lately has been very bad. Oil, air filter and fuel filter have been changed. What could cause this?
View 14 RepliesI replaced my 12V battery yesterday with the Optima yellow top. immediately after, my gas mileage dropped to about 16 mpg.
View 9 RepliesI've had my 2007 Driftwood Pearl Package 2 Touring a little more than a year now. I had been getting 42-46 MPG every tank until I filled up my gas tank today.
View 19 RepliesI have a 2004 Subaru Forrester with a 2.5L engine (non-turbo) and about 137,000 miles. I usually get just a bit more than 300 miles on a tank of gas. About 3 weeks ago, I took the car for a major tune up (and they also replaced a valve cover around the spark plugs area). After the tune up, the car was running great and I was still getting about 300 miles to the tank. Within the last 10 days, I noticed that the gas mileage on the car has decreased - I am now getting closer to 250 miles per tank. The mechanic rechecked the fuel lines and test drove the car two days ago but did not see any signs of leaks. The weather was near freezing for about a week but has warmed up again to the 40's. My driving habits have not changed and I am driving the car the same way as before. I am stumped as to why the gas mileage would drop that much. What might be happening?
View 8 RepliesMy '05 Prius has been going strong with just passing the 200k mark recently. However about 2-3 weeks ago after I replaced the PCV valve, I started getting really bad gas mileage. I'm talking about getting an average of 45 mpg in city/highway combo down to 30 mpg. Filled up my tank twice from empty so I'm pretty sure it's not just bad gas. Highway driving does slightly better than city.
Today I noticed that my acceleration from stop is just absolutely terrible. The car responds really slow and sluggish and takes a while for it to realize I want to go. Low speed doesn't get good mileage at all. It seems I get normal mileage at almost 65 mph, not sure why.
I don't think the 100 degree weather we are having here in Texas is causing THAT much of an effect because last year and two years ago during 100 degrees, gas mileage was normal. What to check? I searched and most talk about cold weather. I have a relatively new 12V gel battery so I doubt it is that but I can try disconnecting it.
Well I work overnight security and I'm able to watch movies in my car or be on my laptop at work but I ruined my battery( didn't have the car engine on) and now that my battery is dying I noticed huge drop in gas mileage .
View 18 RepliesNoticed a drop-off in mileage for there v-10 excursions after 200k? My 2002 ex used to be getting 10-12 hauling a 9k lb work trailer and 14-16 on the highway. After i rolled over 200k though I am down to 8.4-9.3 mpg. My only ideas is to run seafoam through the engine and get the injectors cleaned.
View 3 Repliesthe F150 of my brother has the follow diseases:rough running ticking noises, low mileage per gallone, blue smoke out of exhaust after start, i have ordered the cam phaser, hope, that will be the reason. But today, my brother means, i have to do a test drive, because the truck has no power. and really, feels like missing of one or two cylinders. Very bad performance. Is it possible, that the reason are the phasers?
View 4 RepliesMy friend just bought a 2008 F150 5.4 110k, it ran great all day during all of the test drives, after he gets it home it has started acting up. Most of the time it runs great, but sometimes when you stop the truck the idle will drop down and the truck sounds like it is going to die but so far it hasn't actually died, it starts knocking really badly and runs very rough. If you let it keep running like that it sets P0340. If you rev the truck up it cleans up and sounds fine again and it will even drop back down to a clean idle most of the time. I swapped the cam sensors because it was easy and just to see and it didn't make a difference, I was hoping after switching the sensors the code would switch to the other head but it didn't.
View 14 RepliesChanged my spark plugs and fuel filter but my fuel mileage seems to go down, used to get a average of almost 16mpg on a tank, now I'm down to 13.5mpg and also have the occasional stutter at different speeds/rpms. Is it time for new coils?
View 2 RepliesI bought an 04 f150 super crew cab with the 5.4L triton in it 3 years ago with 50k on it from my great uncle who was the original owner. It's had a tick to it since he had it but the dealership told him they couldn't find anything wrong with it and to get use to the noise. It's ran pretty good up until last couple months where it's been running really rough and not doing the best. It's still hasn't been all the time but more intermittent and comes and goes, but when it's running bad the rpm drops down to about 200 and my motor sounds blown.
When that's happening I could put in neutral and rev it up and it would go back to normal for a bit, but now it's all the time and stalls out even at 70 on the hwy. The codes it throws are, p1000- monitor checks not complete-more driving required, p0345- camshaft pos sens circ error(bank 2), p0022- A camshaft pos timing-over retarded bank 2. Things I have tried-changed all 8 plugs, added K&N air intake, replaced both cam sensors, replaced fuel pump driver module (due to corrosion). Tonight I'm going to clean the throttle body, mas air flow sensor, change fuel filter.
I recently bought a 2006 STX with the 4.6 engine. Occassionally, when stopping at a light, the engine will stall. I took it to the dealer where I bought it and he put it on the computer and found that once on a test drive the RPM's dropped to 490, but it did not stall. He said everything checked out fine and thought it might be a carbon build up, since the truck only has 27,000 miles on it and was driven only around town. He suggested a couple of tanks of higher octane fuel and a fuel additive to remove the carbon.
View 10 RepliesI have an 08 2.0T and it just suddenly had a huge drop in gas mileage. I recently had new tires put on and an oil change (about 35k miles). getting closer to 40k miles now and wondering what could be causing this. Usually I get about 30-33 mpg easy on the highway. Now I'm getting 24-26 mpg. Already checked the tire pressures. they're to spec. no gas leaks from what i can see.
View 6 RepliesTruck is 04 supercrew with 5.4 and 140,000 miles. I have the typical shutter when cruising 55 - 60 and just ease on the throttle to pass someone. I chalked that up to the torque converter unlocking, if I punch it instead of easing into it, it will not shutter. As of yesterday, it acts like the converter is going to full lock up almost immediately. It will bang when it shifts and rpm's drop to lock up range. A few times it has killed the engine when I shift into D. No codes at all, I removed the programmer and installed the stock tune, no change, unhooked battery, no change, fluid is good, and twice after leaving stop signs it worked perfect until the next stop. I believe that it is an electrical control problem.
View 9 RepliesI turned on the car, CONS showed 56.0mpg,
backed out of the garage (about 20 feet) 55.8 mpg,
waited for the garage door to close 55.0 mpg (ICE started),
got to the end of the street (about 200 feet) 54.0 mpg
outside temp was 51F, humid, cloudy
had about 90 miles on new tank of fuel
I know you get big swings in fuel economy when you reset the trip on fill ups but I just thought it was funny that the mpg would drop 0.8 mpg while not moving.
I just locked out the cam phasers on a 2005 f150 with a 5.4. It now idles pretty rough. If I blip the throttle the revs will rise and then drop again, and it barely catches in time to prevent a stall. If I continue to tease it this way I can usually get it to stall. I'm getting no CELs or anything, but I intermittently will get a P035x code (it seemed to rove. I've gotten cylinder 1, 4, 6, but not consistently.). I have chased those around by swapping coils, checking/cleaning the connectors, etc.
I am kind of thinking that these codes are a symptom of my idle issues, and not the actual problem. What could I have done wrong? Could it be a vac issue? I had basically the entire ECU harness and all the vac lines disconnected to do the job, but as far as I can tell everything has been reconnected to the correct locations. I did have an SCT tune done to remove the phasers in the ECU. I installed it and still have the issue, so for now I am on the stock tune just to eliminate any variables.
Could my tune be the issue? Is this how you would expect the engine to behave with locked out phasers and no corresponding ECU tune?
I commuted to LA 2-3x a week. The mileage on my car is now at 90k. I have had an average of 40 mpg since new, but suddenly it began to drop. We took it to our local Toyota dealer and was told it was most likely a cable that needed to be cleaned. That was $160. It didn't work.
View 10 RepliesI was driving up a hill today at about 30 mph with .9 miles remaining showing on my EV battery meter when all of a sudden it drops to 0 EV miles remaining and shows only 2 of the battery level bars (which is very very low), and the engine of course turns on. What happened?
I promise I did not push the EV power bar over its threshold. I monitor that like a hawk. I also know for a fact that it jumped from .9 to 0, because I watch that part like a hawk. This part of the trip is near the end of my drive home and I've done it about 50 times so far with no issues. With .9 miles left at that point on the hill I have always been able to make it to my driveway with .4 or .5 remaining, so this is very odd.
I live in the suburbs, so I do a lot of stop and go driving. For the longest time, I would typically get 25 or 26 mpg city, as per the gauge. I would see the number climb to 41 or so in constant highway driving. I am pretty sure the fuel tank is about 10.5 gallons or so as when the low fuel light comes on, and there is only one bar left on the gas gauge, and I top up the tank, I never put more than about 9.5 - 9.8 gallons in.
All this being said, in the last few weeks I have seen a severe drop in MPG. The gauge is constantly reading about 19.5, when I hit the expressway it will climb a bit, but when I compare the miles driven to the bars on the gas gauge, the bars used to drop at about 20 miles driven, now each bar will drop at around 13-15 miles driven. We are having some extreme cold here in the midwest, as opposed to last winter when I bought the car.
My 03 (129k miles, 2.7 AWD) is up to date on all maint (this summer saw new timing belt etc., transmission service) and oil is current. Spark plugs are due at 131k. Air filter is new, tire pressure maintained at 30-32psi.
MPG has consistently been ~20, slightly more on trips. October 27 to November 26 was 19.8 mpg. Putting on brand new snows (General Altimax Arctic) knocked it down to 17.5 mpg for the next ~250 miles. However, since early December it's dropped again to 13 mpg!
Mechanic just checked for brake drag (none - rotating one wheel turns all 3 others easily); no pulling, rolls well in Neutral. No engine symptoms (missing, bucking) or CEL lights. Power seems a little diminished (for instance, it takes longer to shift during acceleration sequence).
I will add my Lucas Oil gas treatment just in case it may be injectors. My mechanic says he has seen MPG suffer from certain gas brands (and I do wonder if the tank fillup after which the MPG dropped had something to do with it).
I am using a 2012 Prius and I was running around 23KMpL average. For sometime I am seeing my mileage around 17 - 18 KMpL. What could be the reasons for this ?
The only change happened in between is that I had a accident which I had to replace the front buffer.