No start after slipped timing belt/Replacement (3.4L)

Long story short, My 95 Tacoma 3.4L had the rear diff blow-up on the highway one night after work and I had it towed. Up until this time the truck ran flawless albeit a little on the rich side, always started and gave me no problems. I really need my truck back and would REALLY appreciate any input.

Once the rear end seized and brought me to a quick stop on the highway it developed an issue where it didn't want to start easily, which then within a few minutes of idling in my driveway turned into barely staying running unless you held the gas down. I needed the truck in my garage so I rev'd it high (4000rpm) ish dumped the clutch to get it moving against the Diff pinion bearing seizing and got it to the front of my garage and now it doesn't run at all, even with starting fluid. And this is where I am at now...

The engine to me before I dug into any of this sounded like it had low compression( Pretty fast engine cranking like there was no resistance). I found out the timing had jumped about 90 degrees, so I set the crank to TDC, lined up the crank pully's and finished installing the new belt and tensioner. Now that I am done doing that, the engine still has that low compression sound to it when you're cranking it, along with weak yellow spark. I replaced a coil pack and a plug on the corosponding coil pack the spark didn't seem to improve. I didn't check this time around but last time I checked before the timing belt swap, cranking over the engine would soak the plugs so I know they are getting fuel.

So, I am just kind of wondering if you guys had any advice or could let me know if these are possible issues in your opinion. I plan on renting a compression checking kit from the auto store but don't even have enough cash on me to do it until payday unfortunately.

1. I know that the crankshaft spins 2 times for every revolution of the cams, is it possible I am somehow still out of timing even if I am 100% sure the engine is at TDC and the cam marks are aligned. Possible to need to do a single rotation of the cams to make sure it is on the power stroke and not the exhaust stroke at cylinder #1? Or is that not even an issue?

2.What exactly would be causing weak yellow spark, which I assume is leading to my plugs fouling?

3. Editing this in here because I forgot*** I did notice the other day that I do have a chipped tooth on my crank sensor sprocket, but I found the tooth sitting just below it and soaked in oil like it had been off for some time. Would a single broken tooth be enough to cause a no-start condition?

Really, Really need some help here, thanks guys.

 

Bump for help

 

If the timing mark on the crank is aligned with the timing mark on the oil pump, and if the marks on both camshaft gears are aligned with the marks on the engine, the engine is properly timed. Period.

Other than that, I don't have anything to offer you. Sounds like you have problems other than timing.

 

Chipped tooth/gear or the whole tooth/gear came off? Pics?

If you crank gear is mssing an entire tooth than timing is off again and will continue to do so until the crank gear is replaced.

 

Thanks skeez and tony for the response.

Here’s a picture of what’s broke, I’m not home to take a picture of the actual unit. But basically it’s a completely broken tooth on the cam sensor sprocket like circled here.

Would that be enough to throw me off and get a no start condition?

 

Just to narrow it down I would pull the plugs and put a long wooden dowel down #1 and let it sit on top of the piston, to confirm that it is actually topped out when you rotate the crank thru the cycles and back to TDC. Then do the same with the other bank.

Have you inspected the crank and also the keyway and ruled out a spun gear/broken woodruff key

 

I did check #1 with a dowel and it is 100% sitting at TDC, I always check that in conjunction with the marks just Incase it’s been removed and installed incorrectly.

Woodruff hey isn’t a term I’m familiar with but I think you’re talking about the little tab on the crankshaft that the pulley and washer slide on? Everything there looks fine. I’ve even cranked the engine without the tensioner on it (belt is tight enough) and everything seems to be fine mechanically and the timing is still 100% on.

 

Is this an " interference" type of engine. ??? that is to say, is it possible for there to be bent valves caused by rising pistons colliding with open valves with the timing be off so far ?
I know this was a common thing on Honda when the belt jumped time on older civic models. Result being low or no compression.

 

Lucifer: thanks for the response. Luckily the 3.4 isn’t an interference engine, my Porsche 924 is and unfortunately I’m all too familiar with what happens when the timing goes on those.

 

I’m really starting to think this has something to do with the crankshaft sensor crank shown above missing a tooth and throwing off when to supply spark

 

So is it the crank missing that tooth or the cam? Confusing. I believe it would affect how the ecu is reading if your engine is timed correctly.

 

Tooth on the crank sprocket where the crankshaft position sensor reads

 

Gonna go home and try to jb weld the tooth back on even if it stays on there just a few revolutions to see if it lets me get the engine running. Then go pull apart an engine at the scrap yard for a new one if that’s the case.

Fingers crossed, any more input until I do this later would be appreciated

 

anxious to see the results, Good luck!!!!!

 

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jb weld should work, there's no force on it or anything, just spins.

 

replace the sprocket. The ECU is expecting so many short signals before the long signal... that is how the ECU "knows" wha position the crankshaft is in. If all of the smaller teeth wernt necessary it would have not been manufactured that way.

 

What he said above. That missing tooth is your issue. Do not jb weld it back on unless you want to do the job all over again.

 

So last night I repaired the gear ( only to narrow it down and will replace as soon as I get it running).

Still no start with the tooth intact, what I’m noticing now that I did t pay attention to before is that my tach isn’t registering any rpms when I am cranking the engine over, is it possible my crankshaft sensor has gone bad?

 

I’m noticing that someone painted a tooth white on my cam pulley and thinking maybe it’s been taking taken apart and I should try going off that mark? Kinda lost as to why it’s not starting.

Going back to the weak spark, what has effect on spark strength besides the coils themselves? Assuming the timing is fine and the weak spark is the culprit