GenVibe - Community for Pontiac Vibe Enthusiasts

Hi. I have an 04 base with ~90k. Until just recently I was getting around 30-32 general and 34-36 highway, but just recently saw a drop off of 10% or more.Allow me to make a short story long here: On March 21 I drove ~260 highway miles, then drove around town for another 100+. Overall mpg on that tank was 36. I filled up on March 25 and took off on a 2,800 mile road trip, and never got over 31 mpg on the whole trip. I just filled up today and only got 28mpg on mixed city/highway driving.The only change between the good/bad mileage that I made was to add a few pounds of air to my tires, from 32 to 35 cold, which I would think would have helped with gas mileage. Since then I've replaced the air filter and spark plugs, checked the wheel alignment and let my mechanic talk me into adding a can of BG44K. I also had the front brakes replaced, and the mechanic told me that all four wheels were spinning freely, nothing hanging up or dragging. So far nothing seems to have helped.So what else should I look at? What am I missing?

Clean your mass air flow sensor/ reset your ecu. If your maf is dirty you will most likely be getting poor gas mileage. It only takes about 10 minutes and it's not difficult at all.

Most of my driving is under 65 mph, when I go on long trips and cruise at 70, 75, my mileage drops. 32 to 35 psi is a small increase, I doubt it changes the diameter of your tires signficantly, but if it did make your tires bigger, then your odometer would read lower for the same distance. If that happened, and I doubt it, you might have gotten the same mpgs really, but just recorded it as fewer miles. Usually when a car pulls to one side it's a sign of needing a wheel alignment, but you can have alignment problems and have the car still track straight. Too much toe in will lower mpgs. Maybe you hit a bad pothole, periodically check for unusual tire wear.viewtopic.php?f=17&t=6088&#p65128 has an excerpt from the 03 service manual about what to check if mpgs are lower than expected.

Thanks wyatt, I looked up the maf cleaning on here and then found it on my car, I'll stop and get some maf cleaner on my way home tomorrow and do that.joatmon: no pulling, but I had a close encounter with a curb during a recent snow storm so I decided to have it checked. the toe was off a little, but not significantly.

I usually use Brakleen on my MAF, it's about a third the price of Specific MAF cleaner, there is more of it and it leaves no residue at all. Make sure you disconnect your neg. battery terminal as well, it'll reset your ecu to relearn your new clean MAF. When you are cleaning don't get real close to the little bead, spray about half power from about 2 feet away, it's an expensive mistake if you bend it or break the little resistors inside it. I gently clean the dirty side of the bead with a Q-tip soaked in brakleen too, it helps to get the crap off of it. I would spray the inner resistors about 5 times to remove anything off of them. If you want to go the extra mile and help your engine run better with better throttle response just pull the whole rubber hose off and clean your throttle body out. Since you have a newer engine with emissions reducing devices you have an EGR that sends oily crap into your intake which sticks to your throttle body. If you clean this off with a paper towel and clean out the barrel of the throttle body it really helps out the engine. Anyways, good luck and let us know if you need help with something!Oh and welcome to Genvibe

Quote, originally posted by wyatt89 »I usually use Brakleen on my MAF, it's about a third the price of Specific MAF cleaner, there is more of it and it leaves no residue at all. Make sure you disconnect your neg. battery terminal as well, it'll reset your ecu to relearn your new clean MAF. When you are cleaning don't get real close to the little bead, spray about half power from about 2 feet away, it's an expensive mistake if you bend it or break the little resistors inside it. I gently clean the dirty side of the bead with a Q-tip soaked in brakleen too, it helps to get the crap off of it. I would spray the inner resistors about 5 times to remove anything off of them. If you want to go the extra mile and help your engine run better with better throttle response just pull the whole rubber hose off and clean your throttle body out. Since you have a newer engine with emissions reducing devices you have an EGR that sends oily crap into your intake which sticks to your throttle body. If you clean this off with a paper towel and clean out the barrel of the throttle body it really helps out the engine. Anyways, good luck and let us know if you need help with something!Oh and welcome to Genvibe :DHold on there cowboy!! there is both good and bad advice in this post.Cleaning a MAF is good advice, and should be part of a regular service routine.Also the statement about treating the MAF gently is great, don't rub it, don't touch it, don't hit it with a hard force of spray, all good advice.BUT.........DO NOT USE Brake cleaner or Carb Cleaner!!!!!!!Well, you can if you want to purchase a new one sooner than you should I guess.The other sprays seem similar to the average guy but tend to leave a residue on the coatings on the wires and also can harm the plastic in and around the MAF. Err on the safe side, use the proper product for the proper job. If you cannot find MAF cleaner, electrical cleaner would be the ONLY substitute that could be made. I'm not supporting CRC and labeling the same product with various labels, There is a lot of chatter about MAF"s being ruined shortly after cleaning with the wrong product.One size does NOT fit all in this case.It's not unlike using the proper silicone sealer (many scoff at this also) for modern EFI engines. The older style outgasses and affects the operation of modern emission control systems. The newer stuff is safe to use, Silicone is no longer just silicone.Just ANY strong cleaner is NOT good for your MAF. Choose wisely.Dave

Quote, originally posted by wyatt89 »If you want to go the extra mile and help your engine run better with better throttle response just pull the whole rubber hose off and clean your throttle body out. Since you have a newer engine with emissions reducing devices you have an EGR that sends oily crap into your intake which sticks to your throttle body. If you clean this off with a paper towel and clean out the barrel of the throttle body it really helps out the engine. so do you just spray and wipe or do your remove the throttle body and clean it? I should have done the MAF and the throttle body yesterday when i reinstalled the sri

Have you changed spark plugs? if those arent working up to snuff you'll see a big drop.

Quote, originally posted by bull77 »so do you just spray and wipe or do your remove the throttle body and clean it? I should have done the MAF and the throttle body yesterday when i reinstalled the sri Hi, Spray gently, DO NOT TOUCH IT WITH ANYTHING, even that temptation to use a gentle Qtip, resist the urge. Spray and spray again if you feel the need. You will see the dirty "wires" become clean and all sorts of gunk wash away with the cleaner. It is very sensitive and subject to damage with very little effort on your part to damage it.Also, don't drop it. They won't bankrupt you by why spend the money when you don't really need to?It may not do anything to fix your MPG's, it might though, it is easy, cheap and simple to clean and doesn't hurt to do so.Dave

yup -- got the instructions for the maf down, I was referring to the throttle body.

Sorry bout that.Many just spray into the throttle body and wipe out what they can with a rag.I'm a tad (removed) and when I clean one I like to take it off so all the gunk loosened by the solvent doesn't wash into my intake and get sucked into the cylinder. After it is removed I then wipe into the intake housing as much as practical.Do what makes you comfortable.Dave

Brakleen was designed to leave no residue, otherwise it would not be used on brake rotors, pads and anything else that stops your car. It even says "leaves no residue" on the can...? Carb cleaner is a no go for sure for your maf. I've used it a total of three times now since I've owned the car and it has never given me any problems but if you feel the need to you can buy the six dollar a can "maf cleaner".As for cleaning with a Q-tip, DON'T use it on the internal resistor wire (air flow), they are extremely fragile but a quick, (very) gentle wipe of the glass bead looking thing (IAT sensor) will help get all the gunk off of the front of it. Ideally you want to clean it so it's a uniform color all the way around. Last but not least, handle it like it's made of glass, they aren't cheap and you don't want to damage ithttp://forums.genvibe.com/zero...49078 The second post has a picture of the actual maf sensorsBull77: What djkeev said is spot on about cleaning the throttle body.If you have a cable throttle body just open it yourself and clean the bottom edge of the butterfly off as well as the barrel. Push a clean lint free rag or strong paper towel to the back of the throttle body under the open butterfly and clean outwards so if there is gunk you don't push it into your intake manifold. As for a drive by wire, I've never owned one so I have no idea how you would get it to open without the car on? I'm not sure if you can just push on it to open it or if it is direct gear drive which you might strip it if you push hard on it. djkeev: Sorry if I irked you but I was just saying from personal experience that brakleen works. It's not particularly harsh and it's much cheaper but if you "want to err on the safe side" that's totally alright and I totally understand! My car is an '04 and I've had absolutely no issues with it (so far) and she runs like a champ

I've cleaned my MAF twice so far, both times with a generic brake cleaner spray and no known issues. ( wyatt99 must be made of money to buy the Brakleen brand name stuff )However, that's me and my car. Any one else, my advice is to drop the dollar or two extra and buy special MAF cleaner stuff, because MAFs are very expensive, and the car is effectively useless without it.

Haha, brakleen is 2 bucks flat at our local autozone It also has a lot more in it than the walmart or autozone brand too.

Ok, the Carquest I stopped at didn't have MAF cleaner so I bought a can of electronic parts cleaner instead. The MAF sensor didn't appear to be too dirty but I sprayed it a few times and put it back in. My mechanic advised against resetting the ECU, said that it would readjust itself over a short period of time.I finished that tank of gas (it was full when I cleaned the MAF) and only got about 29 mpg, which isn't all that bad for mostly city and a little highway, but not great.Last weekend I went by a Checker and picked up a can of MAF cleaner and tried again. This time I could see dirt and residue coming out as the cleaner drained. I sprayed multiple times until there were no more signs of dirty cleaner. On Wednesday I topped off and was still in the 29mpg range, so I went ahead and reset the ECU. The difference in power was very noticable right off the bat. Don't know about fuel economy yet, but I'm up to 70-some miles and the needle hasn't dropped into the paint yet.Thanks for the help and advise, I hope this fixes things.

Glad to hear, sometimes the ecu just gets cranky