Hello,

I am new to the forum and not the best when it comes to vehicles, so excuse my lack of knowledge.

I recently purchased a 2001 Ram 1500 Sport used. As soon as I bought it, it had some shifting problems. I returned it to the dealership and they replaced the transmission governor solenoid and transducer as well as the serpantine belt.

Now, it runs perfectly fine, except the engine has since started to make a whining/whirring noise when I accelerate. If I accelerate quite slowly, it doesn't make a sound, and if I punch it quite hard, it does not make a sound, but any moderate acceleration creates a high pitched whining noise. Once I have reached 80-90 km/h (50-55 mph) and have to apply less pressure to the gas, the noise goes away. The vehicle runs fine other than the noise. I have noticed no loss of power, although I have not had the vehicle for an overly long period of time, so it's a little tough to judge and there has been no stalling whatsover, which is something I read of on other forums.

I have done some research on the matter and have discovered it sounds like it could possibly be the plenum gasket? Is there any easy way to check this without the vacuum technique I have read about? Also, any other possibilities to the problem?

Finally, if it is indeed the plenum gasket, what would I be looking at for replacement costs with a mechanic? My skills are definitely beginner, as the biggest car projects I have tackled were replacing the radiator and starter/solenoid on a Neon.

Thank you very much for your input.

 

I would check the tensioner pully to see if the spring is bad. It sounds like it could be the belt sqealing. Also, check your water pump by trying to wobble the fan. If it is loose it means your bearing is bad in the water pump. I just went through the same thing and the water pump was binding up and making a similar noise. If your plenum is bad you will notice a lack of power, pinging, and you will be losing oil. To check it just take the throttle body off and look down into the intake. If you see oil in there then you most likely have a blown plenum gasket. I just got mine back from a local shop(no dealer). I bought the Hughes Plenum kit, intake gasket and bolt kit, 180*t-stat, a new front O2 sensor, new throttle body gasket, new o-rings for the injectors, oil change, and the water pump bypass hose. That was about $240. I took it all to the shop and they installed it for $350. I could have done it myself, but work simply takes up all of my time. But, I guess for for around $600, at least I know it's fixed now. My problem ended up not being the plenum though. Turns out that when the dealer replaced the plenum the first time, when the truck was under warranty, they didn't put the rear vally gasket in correctly. It was pinched and hanging down, letting oil into the intake. So, I didn't really need a plenum gasket. But, I am glad that I got the Hughes kit and have to worry about it in the future. Hope this helped.

 

I would think that a slipping or polished belt would make a sound at higher RPMs if it were making the sound at a lower range as well.

I do agree that the belt tension and water pump need to be checked. Have you noticed a loss of coolant?

 

yeah, I think it has to do with the new serp belt, I know dayco polycogs do this. I would take the serp belt off and with the engine cold ( to buy some time without overheating ) take it for a quick spin. remember you wont have any power steering! that will narrow things down a bit.

 

does it have any after market intake? Mine sounds like it has a turbo when i give it gas. Just the sound sucking in from the K&N filter.

 

A similar thing happend to my truck a while back and they ended up replacing the waterpump, pulley, belt and cooling fan and eversince then no more noise.

 

o ring gasket on the air cleaner housing not seated properly?