schwiz

Hey everyone. I've done some searching and some lurking and I haven't found anyone with my exact issue (close but not exact), so I wanted to post up and ask a question.

My check engine light has been on for about 6 months or so now. When I hold the gas pedal at a constant rpm there is a distinct whistling noise coming from the engine bay when I hit around 6k. Also, when I'm driving, and I shift, the engine makes the whistling noise for a split second when I get back on the gas but then goes away as I get harder on the gas. I believe I have a Vacuum leak, but the dealer is certain there is no vacuum leak and couldn't find the problem. They ended up updating my ECU and cleared the code, it then came back on after a day.

I pulled this from another forum, but this is exactly what code is being thrown:
This is definitely not a gas cap issue. I've checked and rechecked that. There is also no corrosion or rusting where gas goes into the tank. The cap seems to be in good shape as well.

I'm perplexed at the issue. The noise is definitely coming from the front end so that leaves me to believe it is not the EVAP system, as that is near the gas tank.

Any thoughts? Much appreciate in advance. Thanks!!!!!!

lynks

What mods do you have?

schwiz

Just intake, otherwise the car is completely stock.

lynks

I am assuming the whistle your hearing is just your intake. K&N intake? Try getting on the gas and listen to the whistle, if you can control the whistle with more or less throttle, the sound you are hearing is your intake.

Does your gas cap open up easy? Try buying a new one and see if that fixes the problem. They are only a fewbucks from.the dealership.

schwiz

The gas cap is definitely not the issue. I've gone through the thing and cleaned it good and it seals as it should.

I have the Injen intake. I will definitely try taking a look at that. The dealership did an engine swap for me 6 months ago, and the whistle started when they did that. I wouldn't doubt if it's the intake then.

jct

hook up a vacuum gauge to it to see if you have a leak some where put a vacuum tee-fitting off the brake booster vacuum line

http://freeasestudyguides.com/engine-vacuum-test.html

lynks

Did you figure this out?

schwiz

I tried adjusting the cold air intake, and made sure that was securely on there, but that didn't fix the problem. Going to have to locate a vacuum leak tester.

Diamondkaye

Having the same problem...Had it looked at yesterday and was told that the tube assembly which is located somewhere around the gas tank and gas cap was causing the problem. Cost to fix $450.00

schwiz

But was your noise coming from the engine bay? It's been way to cold to work on my car in MN, but I'm pretty convinced this is the vacuum switch valve.

TigerDude

I really don't think a vacuum leak will cause a whistling noise. Your vacuum is lowest at higher throttle settings. And you need to look at the lines from the gas tank to the engine (not the fuel lines, the vac lines).

The old method was to shoot starter fluid at the vac hoses until the engine revved.

jct

on my old car i had a vacuum leak right under the carburetor. took me a whole month and a half to find it. turned out i set the gasket wrong...

totally off topic

schwiz

Thread revival:

I found a solution to my check engine light, so I wanted to post up just in case others search for this issue.

I bought a new vacuum valve switch off eBay for $25, installed it, and it did make the check engine light go away. The whistling noise is still happening, but it's far less extreme now. As long as the light is off, I don't think I'm doing any harm.