Toyota Matrix Lazy Starting

My 2005 Toyota matrix started having a lazy start as soon as I had the timing belt changed, and has even failed to start then gone back to lazy starting routine. Is changing the timing belt likely to corrupt the engine timing? Should the mechanic have checked the timing as part of the belt replacement job?

Its late and I am tired but the matrix has a timing chain if my memory is correct. How many miles on the car. Is the check engine light on? The alignment marks should be checked when replaced.

How much did this belt change cost?
How many miles on your Matrix?
If it’s under 150,000 and you’ve changed oil on a regular basis it’s highly unlikely the mechanic changed the chain.
Was it the serpentine belt (there’s no timing belt)?
If he replaced the chain incorrectly you’d get a check engine light because of the valve timing.
Once it’s started how well does it run?

I just looked up both engine options for the 2005 Matrix and my information agrees with Steve… both options had chains.

It would be a help if you could quote exactly what was written on the shop order.

@SteveC76, it has about 98 K. The check engine light has been on for a long time, perhaps extending over more than 20 k miles. I have assumed that is due to" Cat efficiency …" scans have routinely returned only code P0420.

@Circuitsmith, the belt job cost just over $100. I have changed oil regularly. Running error code scanner returns only the P0420 that I have had for a long time. And yes, it is the serpentine belt. I was misled to think the name timing belt also applies when there is only me belt. Once started the car runs well. However I think the idling is a little weaker than before - I sensed this just around, but probably just before the time I noted the lazy starting - it was not such a remarkable difference to be alarming or even to make me remember the sequence of events leading to it, although I am confident that it was just after the belt job.

@the same mountain bike, oh my … that’s quite a name! Unfortunately I cannot trace that order right now. I will update as soon as I do. I try to keep them with respective cars but this time that one might be separated with its vehicle.

Thanks all, and I look forward to any after thoughts you may have after seeing this feedback.

The car has a chain what did you bring it to the shop for the first time? They may have replaced the chain tensioner as they are prone to oil leaks. For $100 I doubt the chain was replaced too much labor for that price. Try to find your invoice and post what was done.

It could be a leaky intake manifold gasket.
It can affect idle quality and will set trouble code P0171 if the leak is bad.
They are prone to failure and Toyota came out with an improved part.
They tend to leak more in cold weather.
I replaced it on my 2006 Matrix a few months ago.
It’s a 30-45 minute DIY job.
There were no symptoms yet, but the gasket had a deformed spot where trouble would have started soon.
It is not a very expensive repair. The part itself is $4-7.