Help with drive belt adjustment

[lh59]

Hi guys,

I just changed my drive belt with a brand new one made by Bosch. It is about half an inch short of the original mark after I tension it. When I start my car this morning, it makes a screeching sound that disappear after about one second. This didn't happen when I drove back in the afternoon. I'm not sure how tight the drive belt need to be.
Do you guys think that I should slacken or tighten it a bit more? I'm quite concern about over tightening the belt and snapping it. By the way, I did the second adjustment for the belt after running it for 5 min. Any help would be greatly appreciated.:thumbup:

Hong

[CTScott]

Without a tensioning bolt, you have to push the alternator away from the block, while tightening the bolts. A hammer handle is a good tool for doing so, but be very careful about where to push against the block, as the oil control valve is a fragile device if you push against it. To check the tension, you could purchase a belt tension measuring device from an auto parts store and tension it to 7.0 to 8.5 mm (0.28 to 0.33 in.) of deflection. The other way to do it is to simply press against the center of the span between pulleys with one finger. It should be tight enough that it only moves about the amount listed above when poked.

[lh59]

Thank you for your advice Scott. I tension the belt a little bit further this morning and the screeching sound has gone. It is now about 1/8 inch away from the original mark.

[DARKSCOPE001]

different belt mfrs could vary slightly but I wouldnt think that it would be so much that it would be much more than a minute amount. These belts actually need to be under quite a bit of tension (not guitar string tight ) But when I did serpintine belts on other cars I always got done thought I had it tight enough. Started it up and it would sqeal like a pig. Really cranked her down with a similar idea to CTscott's suggestion. PROBLEM SOLVED!

Also that new belt is going to do alot of streaching as it breaks in. Run it for a bit (1000-3000) Miles and recheck it.

Best luck :smile:
Sean Scott

[400 dollar yaris]

Any one change their belt and then have issues with idle being too high and get codes for timing? When I first changed the belt, I didnt have it tight enough and it would squeal. Next I thightend too much and loosened it a little bit. Any ideas? Check engine light came on while on the highway and I could tell that the rpms werent dropping as fast when I let off the gas. Do I just have the belt too tight or does this seem like another issue? code (p0011). checked the oil, its just below the full line, barely at all. I changed the oil about 4000 miles ago. I could try changning it early, but I always use pennzoil platinum high mileage and a new filter every time.

Let me know your thoughts. Thank you!

[Leegamer]

Isn't the cam position sensor right above the alternator? I've noticed while using a prybar to adjust my alt bracket that it would be pretty easy to smash that.

[BLH]

It does sound like you may have broken the sensor. Others have reported similar things after changing or adjusting the belt.

If the Cheek Engine Light came On and if you have a code reader it should give you more information.

[CrankyOldMan]

The cylinder just above the alternator is the oil control valve (as CT stated above), not a sensor. It controls the VVT-i for the intake cam. If you've damaged it, that would definitely throw a P0011 since the timing doesn't respond as the ECU expects it to. The bad news is that they're not cheap to replace from the dealership ($90). The good news is that they're very inexpensive at a self-serve parts yard. Just a 10 mm socket for the retaining bolt and a flat head screwdriver to remove the connector. Maybe 5 minutes to remove one, 10 to replace it if you're slow like me. =)

https://parts.villagetoyota.com/p/Toyota_2009_Yaris-3Dr-Liftback-15L-MT/Engine-Variable-Valve-Timing-VVT-Solenoid/62915760/1533021011.html

[xxcanuckxx]

I would say they have figured it out for you. Do a search on the forum, I am pretty sure there is a DIY to replace it. It really is a five minute job, and something that almost everyone has had to do the first time they replace their belt.
Also, I have read in almost every Toyota forum I have been in, that aftermarket belts squeal. I don't know why, but mine has squealed after replacing it, anytime I get a dip in RPMs.
Some people suggest the extra cost to get an OEM belt is worth it?

Sent from my SM-G950W using Tapatalk

[400 dollar yaris]

Thank you all! I will look into this. I definitely used a prybar to tighten the belt. I'm pretty sure I damaged it. It only came on after driving on the highway after about an hour and a half of driving. I will look into it tomorrow and replace the sensor.