Engine/Transmission (1998.5 - 2002) wastegate noise-function?

[jandr]

After searching here I gather the wastegate only allows the boost to go so high then blows off the excess. Correct? How about the noise getting out of the throttle suddenly? I thought that was the wastegate allowing the boost to blow out when the rpm's drop quickly. Am I all wet?

I have just recently got a noise that directly increases with boost rise. It sounds like turbo wine only louder. Do the wastegates stick or not seal good sometimes or if they are going bad? Power seems normal. I put a 4" exhaust on about a week earlier but noise just started. All answers for any of these questions will be appriciated.







2001 4x4 2500 LB, pillar mount boost, fuel pressure, EGT--transmission temp, 4" exhaust, PML transmission pan & diff cover

 

[Steve Campbell]

"How about the noise getting out of the throttle suddenly?"....

They call that "turbo bark" on the site. It is caused by the turbo having to get rid of all of the pressure that is in the system when shifting a stick or getting clear out of the throttle instantly. The turbo actually spins backward... . which is not good.



"I have just recently got a noise that directly increases with boost rise. "



Is your air-box "horn" (which fits between the fender and the passenger side of the air filter box) sucked into the bottom of the air box?

 

[Turbo Horseman]

Doesn't sound good... I've blown the seal on the intercooler hose and that resulted in a loss of boost with a funny noise. Doesn't sound like your problem, so I guess you can rule that out.

 

[jandr]

all better today-lift pump

Well I got up this morning and checked a few things now that it's light out. All bolts are tight. The air horn is in place. All clamps are tight. Don't see any rubbed through areas or holes of any kind.

So I took it for a drive and it's back to normal turbo noise!! I guess at 103,000 mi. funny noises happen.

Can I get everyones input on when to change the lift pump. Plus a few comments on things I've read and heard. My existing pump was put on about 45,000. When I first put on my guage at about 80,000 it ran around 9-10lbs at 70mph or so and 12 to 13 at idle. . Now its down to 7-8lbs. at 70 and 10 1/2 to 11 at idle. Dodge did what they called a flow test at 97,000 mi when they installed my new VP44 ant they said it was good. Mechanics have told me that more than 13lbs into the injector pump is hard on them as well as to low of pressure. I read somewhere that the low side should not be below 4 or 5. Any thoughts or exact knowledge? I figured when it goes down 1 or 2 more I'll change it. I carry one under the seat but would rather do it in the driveway than beside the road!