you mean the belt slipping on the timing gear? if so i believe 1 tooth is 2* so that would be a noticeable difference. if your talking about the crank tirgger, its keyed and pressed to the timing gear so i dont see it slipping a little, just coming completely off.

 

Hey Brian!

The crank pulley part that separates is the outer ring that drives the serpentine belt - the rubber damping material degrades and the actual drive belt ring comes off. Internally and for the purposes of setting timing belt timing, ignition timing, etc, that inner section with the TDC mark stays intact.

So if you're noticing the timing mark on the pulley is off from TDC when measured on the timing belt, more likely it's a slightly worn/damaged keyway for the Woodruff Key that aligns the crank pulley on the crank snout. So long as you can verify true TDC and the damping material is intact, that usually isn't a big deal. If I end up using a pulley like that, I'll re-mark true TDC on the pulley with a paint marker or similar.

Courtesy of Don L. on CelicaSupra, here's an example of the 1JZ-GTE pulley that separated and one that's brand new and perfect:

 

Hey Sup-Bros, thanks for the prompt help! I might have been carrying a basic misunderstanding for years that we'll see if you can straighten me out on.

First, on our cars am I right to think that the Crankshaft Pulley part pictured by Jeff above, also serves the function of harmonic Balancer, and is sometimes also called that? If I'm wrong on that, and there is a separate part that is the Harmonic Balancer, then I guess my original questions should be directed to the Balancer, not Pulley.

If I'm right that the pictured part is what could also be called the harmonic balancer, I thought years ago I learned that the sections I have marked 1 and 2 in the pic below, are not part of the same piece of steel but are two parts separated by rubber or something that could fail and allow the two pieces to move in relation to each other and screw up the timing. Does that idea relate to anything you know of in reality, or is it just another clue that I've smoked too much weed over the years?

 

If I'm right that the pictured part is what could also be called the harmonic balancer, I thought years ago I learned that the sections I have marked 1 and 2 in the pic below, are not part of the same piece of steel but are two parts separated by rubber or something that could fail and allow the two pieces to move in relation to each other and screw up the timing. Does that idea relate to anything you know of in reality, or is it just another clue that I've smoked too much weed over the years?

I'm assuming your mistake is thinking the pully attached to #1 drives the cams? The timing belt is a distinct belt attached to a different pulley than the serpentine belt.

 

If my woodruff key is wallered-out, will my markings for crank pulley TDC and cam timing marks still appear to line up exactly right? (they do). Is there any way to help diagnose if this key could be a problem short of removing the pulley?

 

If it happened to be tightened in the correct position, yes, it can absolutely line up. That would be atypical, though.

What's happening with your car to make you suspect the cam/crank timing is off?

 

The car starts, runs, accel/decel perfectly smoothly, but peak boost is down 3 - 4 psi and power feels down, I dunno, maybe 50-75 whp. Feels exactly like a car with a light boost leak. But it definitely ain't that, or the next ten things that a guy would think of. I've been troubleshooting and finding various things to fix for over a year, but nothing has yet returned the car to her former 530 whp glory. To list everything I've already double and triple checked and fixed is waaay too long to post, at least for here and now.

At this point, all that is left on my own list of things to try is swapping out ECUs, could happen as soon as tomorrow. If that makes no difference like everything else didn't, I'll get an updated dyno to confirm my butt-dyno. Then I'll be out of ideas and will probably have to let some Denver performance shop take over. I've sometimes wondered if before giving up on my own garage, about hiring Jeff for virtual consultation to see if you could think of anything I might be missing.

 

In order for cam/crank timing to reduce boost level, it'd have to jump enough that it'd clearly be off and it'd be down on power and boost because the engine's generally running like crap.
I doubt it's possible to cause a loss of HP like that without being anything but 'smooth' in HP delivery. Has gas mileage been affected at all? Have you done a compression test?

I doubt the ECU swap will change anything, as most ECU/capacitor failures cause weird running problems in every running condition, not simply a loss of HP or boost.

If you've ruled out boost control, boost leaks, various stock twin VSV's and all that fun stuff - there's a lot of "fun" stuff, like the rear turbo WG flapper, the pre-spool valve, and a few other things. Basically you'll want to inspect everything that can leak exhaust internally past the turbos. I'd especially focus on this if it seems laggier than usual, as that's a common side effect of a wastegate that isn't fully closing or a similar malfunction.

Otherwise it's pointing at turbos, sadly. Being in high elevation like our locales requires those CHRA's to spin significantly faster to make the same boost level, and turbos can develop CHRA wear or other issues without instantly causing an oil-smoke sort of situation.

As for hiring, I have a discount for Colorado-based owners of white-glove-worthy 98 QS cars that have bought be beers in Vegas;
So the total cost is (cash register noises) uh, I dunno, a couple more beers? 🍺

 

didnt you change out the exhaust manifold to ported oem manifold?

 

Also look for a pre-turbo exhaust leak, it wouldn't take much of one to cause the issues you're describing!

 

Damn I love those memories of SIV parking lot beers 😁. Hope we're making more of them this October.

I put the ported OEM exhaust manifold on in June '19. Car was running fabulous until roughly 9 months later.

 

if you are down 3-4 psi then you definitely will feel down on HP. how is the wastegate doing? i mean, i was on 3 wastegate spring mods on my stock twins. if the car runs great except for down on few psi, i'd see about whether the wastegate is able to stay closed all the way up top.

 

^ wired it shut, no improvement

 

Brian, this might sound a bit odd, but a while after swapping the 1j into my 89 wayyyyy back in the day (ok, sometime between 2009 and 2010), I had a neighbor with a 4th gen Camaro wanted to run the cars. So, we did, and I don't think he took me seriously, because it wasn't until I started pulling away that I heard him finally floor it. Chivalrous of him, obviously.

Anyway, it felt really laggy. Normally this setup would spool up about 2500 rpm and just pull great from there. However, this time it felt really lame until about 3500 rpm. It wasn't until a few days later when I had pulled the turbo side of the plumbing all out to swap in an upgraded downpipe that I discovered that the little E-clip that holds the wastegate actuator arm in place was uh... it was missing, on my front turbo. So, I effectively went from a stock twin to a stock single.

Might check those E-clips.