- Jan 22, 2014
- 359
Ok so I seem to have been experiencing this for awhile now, can't quite nail it down. When I first start up the truck in the morning, everything seems fine for the first few miles. Then I go to get on the expressway, and it feels sluggish. If I nail the throttle it downshifts and feels fine. I drive like a grandma so maybe thats it, but it still just feels like its not accelerating like it should.
It has no codes and no CEL or warnings or anything. The 02 sensors seem to be acting appropriately, but I am unclear on the 5.3 if there is more than just 2.
In the winter months on occasion I would get a throttle position sensor cel, which I could clear and it would go away for a bit. Since the weather has warmed up, hasn't happened. I have yet to clean the throttle body or the maf sensor.
Things I have done in the past few months:
Changed air filter and spark plugs.
Changed front/rear diff fluid, transfer case fluid, transmission fluid and filter.
Some new front end parts and new tires.
Ran some techron through the fuel system.
I've also noticed a slight decrease in fuel mileage. About 1 - 1.5 mpg. This seemed to occur after I got the new tires, and I was hoping it wouldn't happen as a result of the tires, but maybe it did as I have read comments on some tire sites that people saw increase or decrease depending on tires.
I have a couple of broken exhaust manifold bolts. I don't think its leaking or leaking that badly if it is.
There is a very slight vibration in the gas pedal, seemingly at all times. Occasionally it goes away, either that or I forget about it lol. But when I drive the wifes envoy, it isn't there, so I'm not imagining it.
Thats about all I know. At first I thought it might be because of the exhaust manifold or a partially plugged cat. But if the cat was plugged and if the manifold was leaking, wouldn't the leak mask the cat?
I've considered taking it to the meineke shop down the street to see if they could tell me if the cat is plugged or if I need new 02 sensors. Everyone gives them good reviews, but I have this feeling that the only way to figure that out is shotgunning the parts or at least that's what they will want to do.
I have no history on whether or not the coolant temp sensor or thermostat have even been changed. Seems to be acting correctly though. (I made a post of fans running alot). The fan ran quite a bit yesterday actually but it was pretty hot and humid out, so I kind of expected it. Truck has the electric fans.
Truck is 2007 5.3l with 199k miles on it.
It has no codes and no CEL or warnings or anything. The 02 sensors seem to be acting appropriately, but I am unclear on the 5.3 if there is more than just 2.
In the winter months on occasion I would get a throttle position sensor cel, which I could clear and it would go away for a bit. Since the weather has warmed up, hasn't happened. I have yet to clean the throttle body or the maf sensor.
Things I have done in the past few months:
Changed air filter and spark plugs.
Changed front/rear diff fluid, transfer case fluid, transmission fluid and filter.
Some new front end parts and new tires.
Ran some techron through the fuel system.
I've also noticed a slight decrease in fuel mileage. About 1 - 1.5 mpg. This seemed to occur after I got the new tires, and I was hoping it wouldn't happen as a result of the tires, but maybe it did as I have read comments on some tire sites that people saw increase or decrease depending on tires.
I have a couple of broken exhaust manifold bolts. I don't think its leaking or leaking that badly if it is.
There is a very slight vibration in the gas pedal, seemingly at all times. Occasionally it goes away, either that or I forget about it lol. But when I drive the wifes envoy, it isn't there, so I'm not imagining it.
Thats about all I know. At first I thought it might be because of the exhaust manifold or a partially plugged cat. But if the cat was plugged and if the manifold was leaking, wouldn't the leak mask the cat?
I've considered taking it to the meineke shop down the street to see if they could tell me if the cat is plugged or if I need new 02 sensors. Everyone gives them good reviews, but I have this feeling that the only way to figure that out is shotgunning the parts or at least that's what they will want to do.
I have no history on whether or not the coolant temp sensor or thermostat have even been changed. Seems to be acting correctly though. (I made a post of fans running alot). The fan ran quite a bit yesterday actually but it was pretty hot and humid out, so I kind of expected it. Truck has the electric fans.
Truck is 2007 5.3l with 199k miles on it.