Rough idle - Toyota Nation Forum : Toyota Car and Truck Forums

05TRDTrix · 01-03-2010, 09:52 AM

I just bought a '05 Matrix TRD and it seems to me that it idles a little rough compared to what I expected from a Toyota. Is a noticable vibration normal in these cars?

mikered30 · 01-03-2010, 03:05 PM

Are talking about bad motor mounts or the tach needle bouncing?

05TRDTrix · 01-03-2010, 07:19 PM

The tach doesn't bounce. Just a vibration. Are engine mounts typical to fail?

mikered30 · 01-03-2010, 07:35 PM

Quote:

Originally Posted by 05TRDTrix

The tach doesn't bounce. Just a vibration. Are engine mounts typical to fail?

Not normally. Have someone step on the gas with their foot solidly on the brake and stand to the side to see how the engine reacts.

Woodyg · 01-03-2010, 08:30 PM

the motor mounts are not a common issue. how many miles are on the car? is the car just load.........or is it running rough.these motors have a timing chain and they are kind of load and messy sounding.........you could clean your idle air control valve......while you are at it you should clean the maf also.......has any maintenance been done? sparkplugs?

*a common issue with thses cars are the serpentine belt tensioner.......when it is on the way out ....it sounds like a jar of marbles on the passenger side of the engine compartment....

05TRDTrix · 01-04-2010, 12:28 PM

The car only has 57,000 kilometers on it (36k miles). It seems to vibrate more under load - if you put it in nutral it steadies out somewhat but there is still a vibration. The plugs on the car are original and no other service work has been done except for oil changes and tires/alignment (got all service records).

I did clean the MAF, PCV and throtle body but as far as I can tell it is DBW so no access to the IAC unless its located somewhere else???

Another question, how long can you go in these between oil changes. The records that I have indicate that changes were done between 7,000 and 9,000 kms, does that seem a little late?

mikered30 · 01-04-2010, 04:03 PM

There is no IAC valve on DBW throttle bodies. Can you inspect the serp belt and tensioner?

05TRDTrix · 01-04-2010, 04:31 PM

I can inspect it but what should I look for? Could it cause a vibration?

mikered30 · 01-04-2010, 05:29 PM

Check for squeaks and deflection in the serp belt when running. They are so poorly designed they can cause a vibration. There is a TSB for the tensioner but that really doesn't help much as you are out of warranty.

yotatrix · 01-10-2010, 09:43 PM

I wonder if the motor mounts were replaced with polyurethane ones, they tend to vibrate more

05TRDTrix · 01-11-2010, 08:25 AM

Its been so cold up here (-35C) recently that I haven't had a chance to check anything. I'll take a look at it this week since its much warmer now. I pretty sure that it doesn't have poly mounts in it. I don't think this car has been modified in any way. If I find that there is a problem with the tensioner or otherwise I'll take it in since the car still has waranty - previous owner bought an extended plan.

I've noticed that it is a lot less noticable lately but there is definately still a vibration, more than what I would expect from a Toyota anyway. I'll let you know how it goes.

05TRDTrix · 01-11-2010, 06:14 PM

I took a look at the belt today and it looks fine - seems to run smoothly. I've noticed that this car isn't getting the gas milage that I expected. Is it possible that it could need new plugs? The manual says that they are good for 190k KMS. But that would also explane the rough idle.

mikered30 · 01-13-2010, 08:34 PM

Quote:

Originally Posted by 05TRDTrix

I took a look at the belt today and it looks fine - seems to run smoothly. I've noticed that this car isn't getting the gas milage that I expected. Is it possible that it could need new plugs? The manual says that they are good for 190k KMS. But that would also explane the rough idle.

Could be, I would pull the plugs and take a look at them.