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Showing results for tags 'bad mpg'.
Found 4 results
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Hello, I have a 2001 Chevy Silverado 2500HD, It has a 5.3L V8 Vortec engine with 288,000 miles on it. It has 265/75/R16 AT tires, Things that are original include 6/8 ignition coils, MAF sensor, fuel injectors, serpentine belt, ect sensor (ive heard of problems?) Things that have been done to the truck since I got it include Radiator and water pump, hoses, heater hoses, Spark plugs and wires, fuel pump and O2’s in October 2017. 2 new ignition coils (The other 6 are stock) Oil changes/new air filters, Valve cover gaskets, (Used Throttle body cleaner and MAF cleaner about 1.5 years ago) When I 1st bought the truck in late 2016 was getting around 13-15 hwy which was good for me at the time. About 6 months in, the fuel economy started to decline, though it was not overly concerning to me yet, but within the last 6 months (around September of 2019) it took a hard hit. What was a decent economy, I only get 9 or 10 miles a gallon on the freeway, and don’t even get me started about the atrocity that is city driving. However, I have noticed that my Long-Term Fuel Trim on both banks is anywhere from 14-18% no matter when I check it, hot or cold, idling or at 2000RPM. No one has been able to give me any direction on how to recover any mpg's so far. I use the truck for work daily, I do a lot of driving, but still, it shouldn’t be so low! I just need some guidance here, as to where to (re)start as for fixing this thing. Thank you so so much if anyone has any types of input. Please help! somebody! Thank you
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Having a major loss of power especially noticable when going up hill, and terrible fuel mileage(350 km to an 90 litre tank) have done all the basic things it could be like maf sensor, plugs + wires, Fuel filter, and air filter. I’ve heard talk about it being the cats but they are relatively new and got no codes, and help would be very appreciated! -
I have a 2001 GMC Sierra with the 5.3 Vortec with about 211K miles. Over the past 5 months or so I've noticed the MPGs have TANKED. Be aware this is a Regular Cab 2WD! Early spring last year I was getting about 15-16 MPG with 75% hilly-city driving. Summer came around, I was still receiving 15-16 MPG. As of today, on my last fill-up I averaged 13.4 MPG. Previous two fill-ups were in the ~14.5 range. I very rarely pass the 2000RPM rev-range. I have a code that pops up every once in a while for a Downstream O2 sensor. I have a pending code for a UPstream O2 sensor. I've heard the Upstream sensors have a large play on MPG? Trucks rear end fluid, engine oil, and transmission fluid were changed May 2018. I also cleaned my Air Filter, MAF and Throttle Body about two days ago to attempt a quick fix. Any tips will help. Things I've also tried: Seafoam (2 weeks ago) runs wayyy better Marvel's mystery oil (mid-summer) did not change at thing...
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Hey guys, first post on here and I've got something that stumped me 100%. I have a 2005 silverado 1500 flex vin code Z. It Idles rough it has terrible acceleration, wide open throttle it takes off like nothing is wrong. It misses on 7 every time, misses on 2 every other time, every other cylinder misses here and there. No misses when in park and rpms are kept about 2500. CEL flashes most the time when accelerating (except WOT) otherwise the light is on solid. It has 220k on it and I have replaced alot of parts. New parts All 4 02 sensors OEM Plugs OEM wires OEM Fuel pump OEM Throttle body cleaned 3 stage fuel system cleaner BG Brand Air filter believe it or not OEM again New transfer case (unrelated issue) I have covers the base of the intake with brake cleaner multiple time, no signs of leaks. I've had the smoke machine hooked up 3 to 5 times and again no signs of leaks. At this point what is the best route to take? Remove intake manifold so it's easier to get to and replace the main grounds behind the heads and replace gasket at the same time? Replace the pcm? Replace throttle body maybe? Any other suggestions or recommendations would be greatly appreciated.
