please help me identify a noise - Toyota 4Runner Forum

RodrickHeffley · 08-04-2022, 02:04 AM

I got my 4runner back from the shop about two weeks ago and it's been having a hard time. When I got it back it was idling at about 400rpms and stalled twice, but hasn't since. It now idles at about 700 but still very rough. I started pulling P0171 codes which led me to the MAF, which I cleaned but kept pulling codes. I cleaned it again today but when I started the 4runner I got P0100 and P0110 but they haven't shown up since.

I think it has something to do with this noise that I stupidly haven't noticed until now (because I thought it was the belts squealing but when I had the hood open it was obvious)

I think it's a vac leak however I'm not sure where it's coming from. Help?

Video: 4runner noise - YouTube

Twisted Sid · 08-04-2022, 10:21 AM

What work did the shop do to it?
If there is nothing obviously loose or open that you can see, get a can of carb cleaner and spray it at all the hoses and conditions with the engine running and watch/listen for the idle to change.

Bad Luck · 08-04-2022, 10:40 AM

It's hard to tell when the camera is doing corkscrews and moving so quickly. Take a video longer than a minute so it's not a youtube short to make it easier to pause and play slowly. Also, do what twisted sid suggested above. Carb cleaner/brake cleaner/throttle body cleaner will all work.

RodrickHeffley · 08-04-2022, 10:53 AM

Quote:

Originally Posted by Bad Luck

It's hard to tell when the camera is doing corkscrews and moving so quickly. Take a video longer than a minute so it's not a youtube short to make it easier to pause and play slowly. Also, do what twisted sid suggested above. Carb cleaner/brake cleaner/throttle body cleaner will all work.

sorry, I was trying to get as close to the noise as I could so it'd be more obvious but I guess that didn't help.

I'll get a bottle of carb cleaner on Sunday as Amazon is delivering it then.

I'm not wrong that it's a vac leak, am I?

Bad Luck · 08-04-2022, 11:30 AM

Quote:

Originally Posted by RodrickHeffley

sorry, I was trying to get as close to the noise as I could so it'd be more obvious but I guess that didn't help.

I'll get a bottle of carb cleaner on Sunday as Amazon is delivering it then.

I'm not wrong that it's a vac leak, am I?

It sounds like a vacuum leak to me. You migh check the pcv hose and the hose to the iac is connected in the meantime. Make sure the intake tube isn't folded over and not sealing properly to the throttle body too.

RodrickHeffley · 08-04-2022, 12:21 PM

Quote:

Originally Posted by Bad Luck

It sounds like a vacuum leak to me. You migh check the pcv hose and the hose to the iac is connected in the meantime. Make sure the intake tube isn't folded over and not sealing properly to the throttle body too.

Yeah, I took a second look at it this morning and am kicking myself haha!

It was about 1 am when I was trying to find it so either it was too dark or I was too tired...

Turns out that the hose had come off the PCV and was just sucking in which obviously cause a pretty bad vac leak. Sounds a whole lot better now, but I can't believe I didn't see it, guess I was thinking it was something to do with the MAF hose but I was overlooking something very obvious.

Hopefully that right there is the cause of my problems, which in turn makes me hope my MAF isn't bad, but I'll just have to wait and see if I start pulling codes again.