Kevin I totally understand it's possible but probability depends on multitude of undetermined factors (engine speed, firing order, engine accessory loads, tension of accessory and timing belts,etc . I don't think we can give sure answers to Marcus' questions. Speaking in relation to harmonic dumper.

Yes

Yes

Depends how "lucky" you are.
I'd still would like to know what exactly was replace and how total engine health was diagnosed.
Regardless it might be really hard to pin this down on dealership performing timing belt change.

My Raiders crank pulley had the rubber wear out to where you can see the outer piece wobble. I replaced it and all wobbling ceased and my engine is running fine. I don't have bearings fail or oil pump failure. So I have to call BS.

And the blade came loose on my lawn mower and it was fine too! <img src="/forums/images/graemlins/smile.gif" alt="" />

I'm curious how you know that your engine was fine? OK it did not totally fail, but that does not mean that it did not have extra wear from the bad damper.

Also how does your experiance with a 3.0 disprove that this can't happen on his 3.5 engine? I will agree this is not normal, but this type of failure does happen and there is a reason the factory tests for crank harmonics.

To know for sure the engine needs to be torn down.

This does not mean the mechanic is right... He could be full of it but yes a bad damper can really hurt your engine.

Also when he said "Not Functioning" Did he mean it failed or came loose?

Kevin

Well, did anyone notice these facts:

engine ran perfectly fine for 100k miles.

engine had misfire code only 2k miles after service and continues to do so.

something leads me to believe it is more than just coincidence that all this sh!t decided to go bad right after the service.

the service included:

spark plug replacement
ignition wire replacement
water pump replacement
timing belt replacement
timing belt pulley replacements
timing belt tensioner replacement


even after the HB was replaced with a new one, the check engine light still comes on indicating random misfire. what else could be the cause?

would a bad bearing or worn out crankshaft still cause a random misfire?

does the tech have to remove either the cam or crank sensors to replace a t-belt?

what else would a tech need to remove or replace in the procedure of replacing a t-belt that could possible cause a random misfire code?

I am going to rule out any problems with the ignition coil packs, wires, or plugs since it is always a random misfire and never pin points a specific cylinder, is that a safe assumption?

What if the crank bolt wasn't tightened enough. I'd bet you could get enough movement to confuse the CPS and get a randon misfire if the balancer was loose. The balancer will wallow out from rocking before the crank, killing the balancer. I'd try a new balancer only for starters.

I'd be considering if the stealer did a crappy job of torquing down the crank bolt, which is not easy, and can break the damper all by itself. Which is why if I can't get a flywheel locker, I "torque" the crank bolt down with a 4lb deadblow hammer on the wrench. None of mine ever came loose or broke...

we did replace the HB with a new one and it still throws a random misfire code.

hence the theory of a worn out crank or bearings.

Here is what pops into my head. Up sell up sell. That is what the tech is trying to do. See if he up sells then he gets the job and can flag the hours.

Did he pull the pan and pull a main bearing? Did he pull a rod cap and spin out the upper bearing. Did he put a oil pressure gauge on to see if its still in spec.

Check to see if the tech before some how [censored] up the crank sensor. I have see it happen before.

how do we check to see if the crank or cam sensors are f'ed up??? do they have to be removed when changing the t-belt? are they exposed to possible damage when changing t-belt?

Were the front oils seals done? IIRC, the crank sensor has to come off for that. Can't remember on the cam, but would think so as well.

ill try to post some more info on what to look for tomorrow.