My 94 gmc Sierra 2500 lost power recently and now has a weird whistle sound coming from the engine, but only when I'm in drive driving. It almost sounds like a turbo winding up. My truck don't have 1.

Shea Goertz

Asked by Jun 13, 2014 at 09:47 PM about the 1994 GMC Sierra 2500

Question type: Maintenance & Repair

The engine is a v8 5.7L 350.

3 Answers


Sounds like possibly a vacuum leak.

Shea Goertz

Where would the leak generally be coming from is that be the case? I'm just very unfamiliar with this kind of stuff.


Honestly might near anywhere around the top(intake) portion of your engine. Look and listen for loose/broke hoses around the top of the engine. Follow the hiss sound you are hearing. Hose could be the size of a pencil or up to the size of a large thumb.

1 out of 1 people think this is helpful.

Your Answer

Add photo

Related Questions

  • 2000 GMC SIERRA low oil pressure now won't do anything 20 answers

    We replaced a rear end on our 2000 Sierra 6.0L 4 wheel drive about 3 weeks ago couldn't test drive it right away cause it was stuck due to being in our pasture and it was super soft due to heavy ra...

    2000 GMC Sierra 2500 3 Dr SLT 4WD Extended Cab LB HD


    Maintenance & Repair

  • HAVE 1991 GMC SIERRA 2500 14 answers


    1991 GMC Sierra 2500


    Maintenance & Repair

  • murple missfire 3 answers

    check engine light comes on after 3 hours of driving and only after refueling have replace plugs wires 1 coil filter and 3 gas caps

    2004 GMC Sierra 2500 4 Dr SLE 4WD Crew Cab SB


    Maintenance & Repair

  • My 97 gmc sierra 2500 4x4 has the 5.7 vortec 350. I changed my head gaskets . Got it all back together won't start..... 3 answers

    My valves are adjusted to 1/2 turn past 0 lash . My #1 cylinder is on tdc on compression stroke & at 0 on dampener mark. Distributer pointing a hair advanced of #1 mark on housing . I have good fu...

    1997 GMC Sierra 2500


    Maintenance & Repair

  • What size is my Tranny in my 1994 GMC Sierra 4.3 Litre Engine 16 answers

    Hi Guys, I have a 1994 GMC Sierra with a 4.3 Litre Engine, and I just had my Tranny fall about on me while I was driving. First my Flywheel broke and then shortly after my Transmission started breaki...

    1994 GMC Sierra 1500 C1500 SL Standard Cab SB


    Maintenance & Repair

Sierra 2500

Looking for a Used Sierra 2500 in your area?

CarGurus has 223 nationwide Sierra 2500 listings starting at $2,895.


Search GMC Sierra 2500 Questions

GMC Sierra 2500 Experts

#1 Rowefast
Reputation 150
#2 FordNut
Reputation 100
#3 tennisshoes
Reputation 70
View All

Related Models For Sale

Used GMC Sierra 1500"
1,025 Great Deals out of 56,906 listings starting at $2,300
Used Dodge Ram 2500"
151 Great Deals out of 5,741 listings starting at $2,289
Used Ford F-250"
609 listings starting at $3,995
Used Ford F-150"
3,272 Great Deals out of 216,641 listings starting at $1,500
Used Chevrolet C/K 2500"
286 listings starting at $1,995
Used GMC Sierra 3500"
10 Great Deals out of 303 listings starting at $5,495
Used Dodge Ram 1500"
521 Great Deals out of 13,734 listings starting at $995

Used Cars For Sale

2004 GMC Sierra 2500 For Sale
48 listings starting at $9,500
2001 GMC Sierra 2500 For Sale
8 listings starting at $4,950
2000 GMC Sierra 2500 For Sale
34 listings starting at $5,414