1998 Sileoutte

I have always had a soft tone whirring kind of sound when accelerating and recently it got louder. Then last week it became alot louder and sounded almost different. I started with a check of the all the fluids and found the power steering abit low but not too bad. The sound got better but not gone. I ran it for awhile and then you can hear one sound stop and that one was defenetely the power steering fluid so there was for sure two noises. This second noice resembles the noise I had after purchasing the van two years ago but it's gotten louder.

My thoughts are possibly a fan belt wearing out and maybe this sound is some type of warning, don't know. Second maybe a tensioner I read in another post.

I did check all vacuum hoses and I did find a cracked vacuum line T on the right side of the vehicle close to the fuse panel, I believed I repaired it because I noticed an improvement in the van idle, but no change when accelerating.

This whirring sound only happens when accelerating and driving.

My father in law went for a ride and expressed it sounded like maybe the fuel pump might be going and that's where the noise is coming from. What does everyone think?

You FIL may be right as that is the type of noise a priming fuel pump makes.

Next time when starting the van, have someone turn the key to the RUN position (do NOT start) while you listen for the pump priming in the gas tank. (remove the cap)

Next time when starting the van, have someone turn the key to the RUN position (do NOT start) while you listen for the pump priming in the gas tank. (remove the cap)

I did this and I can hear the pump doing what it supposed to do I think. I can hear something start and then stop. So I"m not sure if that's it or not but I can't really think of anything else but on the way home when I was listening to the sound increasing while accelerating and then stopping every time I let go of pedal. Makes me think that could it be a componant that's run by the drive belt... say maybe the air conditioner because my air conditioner has never blown cold air and I always thought it just needed to be recharged of freon. Could it be a componant that maybe it's bearing is wearing out or something... I dont' know but I really would like to try anything. I might be buying anothe vehicle and if I do I will be able to begin to work on this vehicle. So all ideas are welcome. Thx for the reply RoadRunner

Ok, what you heard WAS the pump priming the fuel system then shutting off after the system was primed to pressure. That's the way it's supposed to work.

Loose or damaged vacuum hoses can make weird sounds too.

Removing the serpentine belt and testing each pulley by turning by hand with a little side pressure makes for easy progress.

AT this time while the belt is off and the vehicle standing still, run the engine for a couple of minutes and work the throttle (don't race the engine though) while listening for the noise.

Some noises seem to have a ventriloquist attached and can be frustrating to detect location.

The whirring sound you suspect may be due to a faulty compressor clutch (MAYbe).

If the A/C hasn't been worked a long time it very well could be the culprit as it will have dried up.

The A/C died when I had my '00 Silo and I never used it anymore. Eventually I found out BOTH rear A/C lines were rusted out (and that's where the refrigerant went)..

Do you have or have had any lights come on the dash during the noise? No CEL?

Well the check engine light was on at one time but it could have been to the problem I was having with the rear brake lines which are fine now. I'm assuming that's what the light was for as it's off now.

I did have a vacuum hose I believe it was and it was cracked and broke off on the left side of the engine, far left. I did a make fix to it and I think it's ok but maybe that's where this problem is coming from. I'll remove it and get it fixed properly to rule it out.

Taking the belt off and increasing rpm in idle is what I will be doing tonight to trouble shoot.

Like I said, don't race the engine.

Also, try not to run the engine too long without the water pump turning or the alternator disconnected.

Ok on the highway the vehicle from what my wife said all the gauges and everything went wierd acting irratically and doing wierd things then the van was drively really slow as she was pushing the pedal all the way to floor and it wasn't hardly moving maybe 30 or 40 km/h and the speedometer was at 120km/h as she stopped at an intersection the van completely died. I towed it and need to try and figure out what has happened. I am pulling the alternator to get tested and charging the battery overnight tonight. Any thoughts