Few questions

[DenverKid24]

I notice when the car is running and I'm parked the idle is at about .7 and ocassionally will fluctuate to .8 and .9. Is that normal?

Also I noticed a sort of hum from 50-60. Just when accelerating but not when coasting. Any ideas? Is that too normal?

Thanks for the input!

 

[YotaZach85]

Can you provide more info on the vehicle in question? Year, engine, transmission, 2wd or 4wd?

 

[ironhippy]

We need a bit more information about your truck, my manual '98 idles higher than my automatic 2000. The auto idles around 500 and the manual around 700, when the fan/AC/etc kicks in, they will go up another 100 rpms or so.

The hum is hard to judge, is it a loud hum? is it coming from the engine? is it coming from the windows? does the engine seem to react to the hum at all? etc. etc. Ideally you could record it and post a video/mp3.

 

[DenverKid24]

Sorry, I am at a computer now.

It's a 1999 SR5 - 4WD - Auto - 3.4L V6.

So about the idling....when its a normal idle like stopped at a stop light it's at about .6, so normal, I think. Then when just stopped and in park, its at about .7 and sometimes it will just go to like .8 or .9 then come back down. Just didn't know if that was normal or not.


Second question. At about 50 to 60 it makes a weird like "wump wump wump wump" sound. Not when really accelerating, but when your foot is just keeping the gas pedal constant. If you let up to just freely coast, it doesn't do it. I only notice around prob the 45/50 - 60 range, don't think it does it when higher speed and not when lower speeds.

Thanks for any info.

 

[YotaZach85]

How often does the idle fluctuate? I wouldn't worry about it too much for such a small amount but you could try cleaning the MAF and the throttle body, it may remedy it.

The noise almost sounds like it could be a tire but you would hear that off of acceleration as well. When was the last time your universal joints were greased? How many miles are on the truck?

 

[DenverKid24]

How often does the idle fluctuate? I wouldn't worry about it too much for such a small amount but you could try cleaning the MAF and the throttle body, it may remedy it.

The noise almost sounds like it could be a tire but you would hear that off of acceleration as well. When was the last time your universal joints were greased? How many miles are on the truck?

They were just cleaned, it doesn't do it too much.

As for the other question, I have no idea. I just bought it about a month ago. Also, it has 121k.

Thanks

 

[YotaZach85]

They were just cleaned, it doesn't do it too much.

As for the other question, I have no idea. I just bought it about a month ago. Also, it has 121k.

Thanks

I wouldn't worry about the idle too much, if it starts jumping up more in the RPM range then it might be a problem.

I would try giving the U-joints a shot of grease and see if the noise gets any better. These trucks are known for rear wheel bearing failure but I'm not sure of what mileage that becomes a problem. Mine made it 220k miles before any issues and my Tacoma made it up to about 240k miles before I did them but I've heard of people having issues earlier.

 

[Antpwr]

dont worry about the idle, it is normal for your auto with 121k on the dial to stay at about 600rpm, and in park to go up to 7-8, it is because in generic form, there is "no pressure on the engine, no force from the tranny to take some of the rpm pressure down". In other words its fine, but if it is always searching for a steady idle, like 5, then 8 then 4 and so forth, or stumbling during acceleration, or even weird hesitation under WOT, then TPS. But it sounds normal. As far as the noise, u-joints, wheel bearing, bad tire, cupped or bad belt in it, or possibly even something not related to chassis. Is the noise present under steady addeleration, fast acceleration, or just crusing along in that speed range, is it something that is really always there and just more noticable under acceleration, if so then it really could be an aray of problems with something in the actual driveline.

 

[DenverKid24]

dont worry about the idle, it is normal for your auto with 121k on the dial to stay at about 600rpm, and in park to go up to 7-8, it is because in generic form, there is "no pressure on the engine, no force from the tranny to take some of the rpm pressure down". In other words its fine, but if it is always searching for a steady idle, like 5, then 8 then 4 and so forth, or stumbling during acceleration, or even weird hesitation under WOT, then TPS. But it sounds normal. As far as the noise, u-joints, wheel bearing, bad tire, cupped or bad belt in it, or possibly even something not related to chassis. Is the noise present under steady addeleration, fast acceleration, or just crusing along in that speed range, is it something that is really always there and just more noticable under acceleration, if so then it really could be an aray of problems with something in the actual driveline.

It's really just when cursing along in that speed range with the foot on the pedal it seems.

Here is recent things I've done:
New head gasket
New water pump/timing belt/drive belts
New TPS sensor
Transmission flush

Then some other stuff like break work, new tires, and what not.


Not sure if any of those could be effecting it, I doubt it but I don't know.


But yeah, I'm not really worried about the acceleration, more so the other problem with the 'woomp woomp woomp' type noise.

 

[DenverKid24]

Bump for any other suggestions?