Hello all,
Im new here and thought maybe I could get some support. This weekend I put in a new timing belt, water pump, idler and tensioner pulley and tensioner. I have an FSM and went by the book pretty much. Most everything went smooth. The belt was a pain to get on but id did go. The crank position indicator on the crank gear was dead on the mark at 12 o'clock as were the cams I was quite happy to get them right on the first attempt. I verified #1 cylinder was tdc using a long 1/4 inch extension. As I understand it, though, as long as the marks line up its should not matter. Nonetheless, on first start, it runs like there pee in the gas. Terrible rough idle and dies. I am attaching a few pics to show cam and crank position. I measured resistance of both cam and crank position sensors and both are within FSM specs. I was wondering if anyone might have any suggestions. I did take the negative terminal off for about 20 mins thinking it might let the ECU re-learn everything but I am at a loss. Any advice would be appreciated. I didn't take a pic of the crank gear as it was right on the mark but I took a pic of the main pulley. It look like its right on zero which I think is correct. Prior to changing everything my 4runner was running fine.

 

Maybe it's just the photo angle, but the P-side cam gear doesn't look like its lined up with the backing plate notch, if you didn't rotate anything while its apart you must be off a few teeth on the belt.

 

Malcolm, Thanks for the response you are right, it IS the angle of the picture. I was attempting to get both cams and the balancer pulley in the same shot. Looks like I'm a crappy photographer AND mechanic. if you are looking straight down the marks do line up correctly. I actually rotated everything while the belt was off only because I know the motor in non interference and to line the marks up. I should have marked their position before removing old belt. Still I keep reading that as long as the marks line up I should be good to go. This is not the case. The engine struggles to start but will run. It runs really bad though. Bad enough I wouldn't consider putting on the street.

 

Your timing is out of phase, you cannot rotate the crank or cams while the belt is removed because your valve timing will be out of phase, you will need to remove the timing belt and get the valve timing in phase as it has 4 different stokes intake, compression, power and exhaust, everything will line up but your valves are opening and closing at the incorrect time..

It is non-interferance so if you break a belt it won't destroy the engine (never seen this happen to this timing belt yet) but your suppose to get the motor at TDC on #1 cylinders compression stroke (valves closed on #1) with all timing marks lined up then remove the belt and reinstall keeping everything in phase.

 

This makes complete sense. I know with the setup like it is. # one cylinder is tdc but I don't know which phase the cams are in.
Thank you for the insight Malcolm!

 

 

It must be out of phase, as the timing isn't correct, perhaps he is out 180* on 1 cam or off by a few teeth on the crank.

 

If you put up the belt facing out instead of in, the cam marks line up and the crank mark is like 5 teeth off. If that is the case of what happened, he would be running around 30* retarded or advanced and would barely run. I know when I did my belt last, in the rain, I was tired and cold and had the belt facing the wrong way out and spend the better part of 2 hours trying to figure out why my marks were off.

 

Another possibility is broken teeth for the Crank Position Sensor pick up on the back of the crank sprocket, that will also cause starting issues.

 

I want to say thanks for everyone's input on this. At this point, I have been so busy I towed my 4runner to a trustworthy local repair shop. Malcolm hit it, my shop guy said when he pulled crankshaft timing gear off there were two teeth missing. Number 4 and number 6 cylinders were not firing. I was very meticulous when I took it off not to drop it and did not notice any teeth missing. Maybe it was brittle considering it had 180K miles and with a new tight timing belt, the pressure on the pulley caused it to fracture, although that's just an assumption. The new pulley is going on as we speak. I will update when I hear back from my mechanic if that resolves the issue.

Thanks again to all.

 

JUST to correct the record here...

This is incorrect. The post below has it right.

The valve timing is entirely controlled by the cams. If they are at TDC, that is intake stroke on #1, full stop. The crank just makes the pistons go up and down, twice, per cycle. There is no difference between intake and power or between compression and exhaust as far as the crank goes, there is just up and down. The cam and crank sensors tell the ECU when both are at TDC, and the ECU makes the ignition cycle and fuel injectors conform to how the hardware is.

The 180° out of phase thing applied back when the ignition was mechanically controlled by a gear train linking the crank and a distributor. Then the crank had four strokes, because of when the gears told the dizzy to fire. Cam and crank sensors and electronic ignition and fuel injection made this a thing of the past. Just get both cams and crank at TDC and let the ECU do the rest.

You do need all the teeth or the ECU can't do the job.

 

Correct, I was thinking of a motor that doesn't have geared intake and exhaust cams and many other motors that require a TDC on #1, so this doesn't apply to this specific motor, my apologies. Glad you found the issue and solved your problem, that can be a difficult 1 to diagnose..

 

UPDATE: So I heard back from my mechanic. As it stands, I did install everything correctly. There was a broken tooth on the crankshaft timing gear that I did not notice. Just one tooth but apparently one is enough to piss off the crank position sensor enough that it will not run correctly. He gave me the old gear and I just don't see how a tooth broke. These gears are pretty robust in their construction. Nonetheless, it's running pretty smooth with the new gear. I happen to have a buddy that is the parts manager at the Toyota dealership where I live. He quoted me $67.00 for the gear. My mechanic charged me $68.00, plus a bunch of labor. Live and learn. I would suggest that anyone else doing this job at home to consider replacing the crankshaft timing gear in the process or at least give the gear a very thorough once over and save from possible future headaches. I replaced the timing belt at 100K in the exact same fashion and had no issues. This time I replaced the idler pulley, tensioner pulley, tensioner, water pump, both cam seals and the crank seal.

Thanks again for everyone's input,
Scott

 

wrong post, disregard