Timing belt off, effects?

eclipse
mitsubishi

#1

my cars running really poorly, replaced the head after an overheat. before it was pouring water from the exhaust. thats done with so im thinking maybe timing belt. what are some/all of th effects of the timing belt being off a tooth or two. no banging sounds so the valves arent hitting. just runs like doggy poopy, kinda nervous to leave the driveway with it in case it dies randomly. timing belt effects?


#2

It would run exactly as you describe. Please, however, chose more family friendly terminology.

However, there are other possibilities here, such as misadjusted valve lash. But before going there, you really need to carefully recheck the valve timing. The timing belt may very well be improperly timed… and it could be only on one camshaft.

Post back.


#3

theres 1 camshaft, it has poor idle, sounds like cylinders are hitting wrong or one is inactive, but i pulled the plugs and they all made a difference so i know theyre getting the juice they need. goes from almost dying in idle to 1k RPMs back and forth, the O2 sensors were leaking smoke from the exhaust, probably just poor tightening on my part, it used to have a deep sound all the time, now in idle its deep but if i rev the engine it has a very slight whine to it but you can definitely tell the difference in sound.


#4

It is likely out of time and you shouldn’t drive the car until getting things back together in time. You didn’t mention year and model but as I recall the 4 cylinder DOHC Mitsubishis had cam marks that lined up on the edge of the head. If I’m correct I recommend that you use a straight edge lined up across the cam pulley bolt centers and the cam timing marks to confirm that the two cams are correct and then confirm the crank pulley is on the mark. Of course many Mitsubishis had a small balance shaft belt behind the timing belt. If so did you get that belt correctly installed, i.e., inserting a screw driver through the block to check whether the balance shaft was up or down? But if you have a good shop manual you already have all the answers and just need to retime the engine paying closer attention. It’s almost certainly an interference engine so be very careful and get the tensioner pre-load set before releasing the tensioner.

Edit-ignore above post as you indicate it’s a single OHC engine. What year and model and engine are you dealing with?


#5

2011 eclipse gs, 1 cam, still a mark on the head cover, what i just learned is that my dumb ass lined them up then let the adjuster loose, i lined them up before there was any tension on the belt, thus putting pressure on pulleys and marks to be moved. couldnt find a 2011 eclipse book anywhere im going off of videos and common knowledge.


#6

I looked at the parts on your engine and saw that the tensioner pulley has an off center hold down bolt hole but no hole or flats to twist it and pre-load the belt. What have the videos shown to get that pulley twisted?


#7

When timing belts slip out of time, but not enough to cause the engine to plum stall out, two common symptoms are poor acceleration and backfiring. See that little icon at the bottom of your post that looks like a pencil? Click on it, then you can edit out the inappropriate language. Remember this is the Car Talk Website, so a little bit of off-color language is ok, but it should be limited to language you’d hear on the radio show.


#8

We just removed the tensioner and put it back in once everything was aligned then released it.


#9

How many cogs was it out of time?


#10

No clue but there’s no metal to metal sound so im assuming a tooth


#11

But did you rotate the tensioner pulley to pre-tension the belt before releasing the tensioner?