1998 Altima : timing chain skipping a tooth

[Checkered-Member]

Hello all,
I have an auto 1998 Nissan Altima with 153K miles, never had any major repairs other than a water pump at 75K, maintained constantly.

The other day I accidently did a neutral drop on the freeway (revved the engine in N and put it in D) The transmission engaged (~5,000 rpms) very violently giving the whole car a big jolt, then the engine stalled …I pulled over and was able to get it to start but if I let it idle it will die, so I need to give it gas.

Below 2K RPMs it backfires and wants to stall, above 2K is runs ok, but very rich with a few misfires (I was able to get home 12 miles driving this way) over 3K rpm’s engine starts to shakes, no check engine light, no codes, no leaks, I can feel the transmission shifting ok between the gears so it’s doing fine.

All the symptoms point to a timing chain skipping a tooth,
1. Is there a way to confirm that the timing chain does indeed need to be reset?
2. Can anything else cause these symptoms?

I was able to get a quote for $700+parts to replace both timing chains. As far as repairs, if the lower timing chain skipped a tooth (most likely because it’s so long) can just the upper timing chain be reset to correct the issue? Saving a bunch of money because only the upper cover and cam sprockets need to be removed?

[PapaSmurf2k3]

Sounds like you have a good theory there. The symptoms DO sound like valve timing.

You can pull your valve cover and look at your cams. With the engine at TDC on the compression stroke (rotate the crank pulley so the red notch is at the dowel), your intake cam lobe on cylinder #1 should be pointing in the 9 o clock to 10 o clock position. The exhaust lobe on cylinder 1 should be at the 2 to 3 o clock position. If you got to TDC on the exhaust stroke, cylinder 4 will be on the compression stroke, and you can just check the lobes there.

If they are off, yes, you can get away with just setting the cams via the upper chain.