Expert help needed: New Timing belt = cylinder 2 misfire?

[hsk8te2006]

Hi Everyone,

I need help from anyone with a lot of experience with these engines. I recently ahd my timing belt replaced, along with it's tensioner pulleys.

As soonas I picked the car up, it has run a little louder and harsher, definitely vibrating mroe than it did before, althuogh the guys at Meineke said they couldn't feel any vibration or harsh sound (of course). They installed serp. belts that are squeaking, and they even forgot to put one of the bolts back on teh timing belt cover. (One not happy costumer here).

Then, last week I'm driving along and the car starts to run extremely rough,a nd the CEL comes on. Well, when I get home I plug in my laptop and OBDII software, and it reads a cylinder 2 misfire.

Unpluging the sylinder 2 spark wire made no difference, so I'm sure it's cylinder 2.

Somtimes, it will run smooth for about 10 second when first started, and then start to run rough again.

Does anyone have any ideas what went wrong, or if there is an easy to make mistake when doing a timing belt change that can result in a cylinder 2 misfire?

Thanks for the help guys!

-Jonathan

 

[bostonhatcher]

If your motor vibrates and all of your timing belt marks are aligned then your balance shaft isn't. Even with the balance shaft belt, if the marks are aligned then it could still be off, and you'll have to rotate your balance shaft sprocket 360 degrees.

 

[hsk8te2006]

Thanks. I'll have the meineke guys look at that tomorrow when I take my car back to them to fix whatever they did.

Any ideas on the misfire?

 

[Old Mitsu Tech]

I would almost bet that the rear balancer is out of synchronization. As far as a miss, that could be a lot of things. Do a compression test just to humor me if for no other reason. If all is well there, look at your plug wires where they go down into the head and see if you can see any white spots which would indicate spark jumping through the bakelite. Just make sure that the tensioner is set properly or you're going to be real upset with the results.

Good Luck

 

[hsk8te2006]

What is a rear balancer? (Sorry... I'm not very well versed yet on engine internals)

I'm afraid that I don't have the equipment for a compression test right now. Is it expensive or hard to find?

FYI all the spark plugs only have about 5k miles on them, but the plug from sylinder 2 is fouled and black... would this be a result of or cause of the misfire?

Which tensioner are you referring to?

THanks!

 

[bostonhatcher]

Is it possible that it's just picking up misfire from the motor be unbalanced?

Forget what I said about the balance shaft. I've read it closer and change my mind.


Go pull your #2 spark plug out, put it on the wire and have a friend turn your car over.
I would almost bet that your coil pack, wire, or plug is out and that it isn't even firing.

A misfire on your motor will cause it to vibrate severly.

 

[hsk8te2006]

Ok... but, there was a minor (but harsher sounding) vibration for two weeks, then the sever vibration/shaking started later when the CEL came on for the misfire. Any ideas about the vibration before?

Also, do you think it is safe to turn the car over and run it with the spark plug out and one of the cylinder chambers open to the atmosphere?

 

[Splitpi]

There are two balance shafts on the engine. One is driven from a belt that is driven off the crank pulley. This is called the front Balance Shaft (or more appropriatly by Mitsu a Silent Shaft). The second balance shaft is on the back side of the engine and is driven off of the Oil Pump pulley (which is driven by the main timing belt). The issue with this rear balance shaft is that it can be lined up on the timing marks and still be 180 degrees out of phase... due to the timing mark being the timing belt for the oil pump. Think of a balance shaft as a heavy chunk of metal in the shape of a cylinder cut in half length wise.

Its an easy mistake to make, but requires removing the timing belt to fix. If you can handle the vibration then it won't cause any issues. It just makes the engine vibrations seem worse.

This issue though has nothing to do with Cylinder 2 misfiring.

 

[Old Mitsu Tech]

The rear shaft has to be phased as it revolves at one third the speed of the engine which helps to dampen vibration. If you don't have it phased right and even though the marks line up it will vibrate. Take it back to where you had it installed, find and download the proper way to install a timing belt and give it to the installer. It may insult him so be careful. You can also remove a bolt in the center of the rear balancer, install a 1/4 diameter rod and when your rod passes through and the marks line up it's phased properly. Get the download from here or vfaq.com. The miss could be anything. Like I said, check the wires and be sure to check the connectors on your injectors. Something should pop up.
Good Luck

 

[thatboyjose]

I need to know if this was resolved. I'm having a similar issue.