Questions and Answers

Sentra Starting Noise Q. The car is a 1994 Nissan Sentra, Automatic, I think it's a 1.6 liter, mileage 80,000. I believe it's fuel injection. Problem is a noise heard when starting on cold mornings (or evenings for that matter). Hard to describe the noise but it's like it's clearing it's throat. (As opposed to a grinding metal sound).

The car starts fine, and the noise is only on startup, again when it's cold. I would just like to know what causes that noise and if it can have serious implications even though it's been like this for a while and I haven't noticed other problems. Thanks for your help and appreciate your time, these Q&A boards are really informative.

David

A. I think the noise you're hearing is like a ringing, grinding noise. A common problem with the Sentra was soft ring gears (the gear around the flywheel). The teeth on the ring gear tend to wear out and when the starter tries to engage it, it doesn't make full contact and just grinds. After several attempts, the starter will engage and turn the engine over.

Eventually it will get to the point where the starter will no longer engage the ring gear and you'll be stuck. Since that engine stops in one of three positions, the same three places on the ring gear will wear down and the time it takes to get to the point of no-start will be determined by how many times the engine stops in a particular position.

The transmission will have to come out and then you have two options, replace the ring gear or replace the whole flywheel. Since the labor to install a ring gear is almost the same as the price of a new flywheel, I have always opted for replacement.

I also recommend replacing the starter with the flywheel since the starter teeth will also be worn down. Not to the same extent as the flywheel, but possible enough to damage the new flywheel.

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