Suburban Won't Go Over 40 ph

Maintenance/Repairs
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1

My daughter owns a 2006 Chevrolet Suburban with 130,000 miles- she ran it down to a quarter tank of fuel, which may or may not matter- now, if won’t go over 40 mph without stumbling- What do you think? Ignition module? Or something else? Thanks.

2

ignition modules rarely if ever fail on these trucks. She should be able to run the fuel lower assuming the gauge is correct. However running an electric fuel pump out of gas is a death sentence. Sounds like maybe plugged catalytic converter. Try removing front O2 sensors and test drive.

3

What’s the general state of maintenance? Spark plugs? Wires? Filters? Check the fuel pressure. Exhaust blockage leak also as pete p suggested.

Do you mean it literally won’t go over 40 mph? What, exactly happens at that point. Describe.

4

I would expect a 2006 Suburban would have a CEL under those conditions. Do you have a check engine light on?

 A CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.
5

According to my daughter, the car “stumbles” and won’t run over 40mph- I don’t know the state of maintenance on her vehicle… Her exact words: “It’s a 2006 with 130K, when I get down to 1/4 tank, I can’t drive over 50 mp or the engine cuts out, like it’s not getting gas.”

6

My first guess would be a fuel pump on its last legs. Someone needs to get a pressure gauge on it & evaluate.

7

just talked with my daughter on the phone- she said “It only stumbles when I’m down to one-quarter of a tank… and then (at a quarter tank) it stumbles when I try to drive over 50 mph”- she told my wife that parts were “so expensive” which is why she hadn’t fixed it- My comment: “Can your boyfriend fix cars? Or do you have any friends who will fix it for cheap?”- in my experience, parts are about half the cost, labour the other half (here in California, labor is $85 to $105 an hour, both at the independents as well as the dealers)

8

Oh, and check engine light is NOT on