Bogs down when stepping on it

[Emir Hamidovic]

I have a 2009 Chevy Silverado 2500 HD 6.0 l. When I'm driving down the road and if I need to accelerate real fast or want to speed up when I press the accelerator pedal the truck downshifts and gets stuck on a certain RPM and it actually slowly decelerates. I am leaning towards the fuel pump and fuel delivery like it's being starved but I really don't want to tear part into the gas tank to get to the fuel pump in case that's not the problem. If anybody has had a similar problem or knows what I'm going through please help thank you

[CamGTP]

Testing for fuel pressure would be done first before you ever started tearing into the fuel pump. You can do that if you buy a tester or rent a tester if they have them at parts stores. The gauge can be taped to the windshield if the hose is long enough. You'd want to see roughly 50psi at idle and upwards of 58-60psi under load.

 

It's hard to say what the exact problem is without watching a scan tool or looking at the truck in person. For all we know it could be a exhaust problem under heavy load, it can't get the gases out fast enough because of a restriction. If it was really bad the exhaust would be glowing at night near the cats.

[Supreme Pizza]

I would not replace any parts at this point. Don't guess. You might replace a good part with a defective part - and now you have 2 problems and no idea where or what the problem is.

 

I would suspect that you have a check engine light on. Most auto parts stores can read them for you for free.

 

Even if the CEL light is not on, there can still be pending codes that can be retrieved.

[Supreme Pizza]

2 minutes ago, CamGTP said:

Testing for fuel pressure would be done first before you ever started tearing into the fuel pump. You can do that if you buy a tester or rent a tester if they have them at parts stores. The gauge can be taped to the windshield if the hose is long enough. You'd want to see roughly 50psi at idle and upwards of 58-60psi under load.

 

It's hard to say what the exact problem is without watching a scan tool or looking at the truck in person. For all we know it could be a exhaust problem under heavy load, it can't get the gases out fast enough because of a restriction. If it was really bad the exhaust would be glowing at night near the cats.

 

 

Well said.

[richard wysong]

I agree, check the fuel pressure and volume first, if it has a fuel filter change it and check it for water and sediment by dumping/ blowing it out.  there are numerous things that can cause those symptoms so data stream info/ codes are essential for accurate diagnosis. codes do NOT mean replace the part necessarily but give you a path to follow to find the problem. sounds like exhaust restriction to me, you could try removing the upstream 02 sensors and taking it for a test drive, make sure the exhaust from the missing sensors doesn't damage anything

 

[dna9656]

Yeah definitely get your truck scanned, Many a time I have seen guys take the truck to a competent mechanic at a professional shop to get it diagnosed, it's ALWAYS been money well spent. Most places flat rate 1 hour to troubleshoot. If there is a trade school around you might provide a "training opportunity" to the class...and get it diagnosed for free or pretty cheap.

Digging into fuel tanks isn't hard work, just a pain and it's got lots of potential safety issues, you really got a bomb on your hands even when it's empty. I have repaired more than a few  metal tanks (by soldering patches made for scrapped fuel tanks) I know what is SUPPOSED to happen when performing repairs but it seldom does. Bottom line: if you drop the tank, empty it, store the gas in approved containers or sell to your friends. Vehicle Exhaust Gas is used to ventilate the tank, it doesn't have much O2 in it, it's warm so it will hurry up fuel evaporation That's what is supposed to happen. Most people just buy a new tank, I guess because few have the skills to repair them. Plastic tanks in theory can be welded but I don't know if that's legal or best practice...

[Emir Hamidovic]

I should check the fuel pressure, but now that you mention the exhaust part i think im gonna check that out before anything else. My cats have been gutted by previous owner. However the exhaust pipes have been altered and re welded. Not sure why. Thanx for replying to my question

[redvett]

Check & replace air filter and also check the tubing going to the throttlebody, your truck is 12 years old and the tubing maybe collapsing on acceleration.