You are here:

Chevrolet Repair/305 v8 whistle

Advertisement


Question
Ok I have a 93 chevy 1500 v8 tbi p/u and every time I drive the truck long enough to get it to running temp it starts to have a high pitch whistle. When I'm driving the truck and press the gas the whistle gets softer. If I press the gas hard enough the whistle goes away, but after I let off of the gas it comes back. My dad and I have replaced the idle air control and rebuilt the throttle body and that has not fixed it. I think I is one of the fuel injectors because I did not replace those when I rebuilt the throttle body. It is not a vacuum leak because I already checked all possible hoses. Any suggestions before I replace both fuel injectors?

Answer
It is a vacuum leak ,most likely . You missed it. Get a squirt bottle and use water. spray anywhere suspect,and when the noise changes, you found the culprit. There are lines that have manifold vacuum as far back as the gas tank. There is supposed to be some hiss, as air gets sucked past the throttle plate.

Chevrolet Repair

All Answers


Answers by Expert:


Ask Experts

Volunteer


Daniel Ostrowski

Expertise

Any questions pertaining to Alignment, brakes, emissions systems, major engine repair foreign and domestic, performance and the not so common questions such as the chemistry related to emissions, What scavenging is, piston offset, purpose of harmonic balancer etc.

Experience

troubleshooting mechanicle failures. Differential repair, electrical systems, disc and drum brakes {all}.Major repair all aspects of a vehicle except paint and upholstery.

Education/Credentials
Protech 4 way [thrust angle alignment]certificate.bear smog license program certificate. Protech brake certificate.

©2016 About.com. All rights reserved.