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I have a 4.8 engine sometimees it drops down to an idle and…

Customer Question
I have a 4.8...

I have a 4.8 engine sometimees it drops down to an idle and won'tgoany faster then all of a sudden it jumps to full speed

Mechanic's Assistant: How many miles are on the car? What size is the engine?

220000 4.8

Mechanic's Assistant: What is the model/year of your Chevy?

2004 gmc

Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far?

I wanted to change the fuel filted but coouldn't find it

Submitted: 2 months ago.Category: Chevy
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Answered in 8 minutes by:
5/31/2018
Chevy Mechanic: Eric, Automotive Repair Shop Manager replied 2 months ago
Eric
Eric, Automotive Repair Shop Manager
Category: Chevy
Satisfied Customers: 35,168
Experience: 20+ yrs. experience as repair shop manager and technician.
Verified

HI,

what model GMC - envoy, canyon, Sierra 1500, 2500, Savannah?

When this happens, are any warning lights such as check engine light on?

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Customer reply replied 2 months ago
Check engine light has Ben on for2yrs
Chevy Mechanic: Eric, Automotive Repair Shop Manager replied 2 months ago

HI,

Ok, there are 2 possible causes of the current issues, either the APP(accelerator pedal position) sensor or the electronic throttle body. To determine which of the 2 is faulty, you need to have vehicle scanned for fault codes which will tell you which is at fault.

Unless you leave in California, you can run it by any major parts store and they will do this for free for you

If for any reason, you can't rate my answer OKAY, GOOD, or EXCELLENT/3 STARS OR HIGHER today. Please reply and let me know why, so I can help more/better. All follow up responses are FREE, after completing the required rating
Please remember to rate service using the separate rating page. Thank you

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