I just finished replacing the clutch on my '89 n/a RX7, and everything was working well, until I took a sharper corner on one of the country roads around where I live. As I was taking the corner the engine seemed to hesitate a little, and then the tachometer stopped giving me a reading. I got it back to my home, with a brief flutter in the engine every once in a while, and parked it.

This morning it started up fine, and I even got a tachometer reading. But after a few seconds the reading stopped and once again there was a brief studder from the engine. And when I just went outside to get some lunch, the car wouldn't start(made a similar sound to when you try to crank a car and the battery is dead).

It feels to me like it's simply a connection I may have rubbed the wrong way while I was tinkering with the transmission, and I saw some posts relating the starter and tachometer, but nothing that explained it well. So any help with this would be appreciated.

 

They're really two very different and unrelated things. Since you were working in the area of the transmission, you probably didn't secure the main ground well enough. That would cause intermittent starting problems, but I can't think of any way that would affect the tach. The wiring for the tach would not have been touched when dropping the transmission.

 

That works for me. It would also explain why it starts cold but not after the engine has had a chance to warm up.

As for the Tachometer, is there anywhere in specific I should check, considering that it will work when I first start the car up, but decides to fail shortly after moving about? Or should I just check all of the connections just in case...

 

same thing happened to me but it suddenly began wrking again.

 

The tach signal comes from the trailing coil(s) If there is a break in the signal wire it will be intermittent or non-working. As well the wiring going to the tach could be suspect. Nothing to do but get a service manual and a multi-meter and start checking things out.

 

The bad ground may cause tach problems. Nothing works when it has a bad ground or noisy power going to it.

Clean up the ground and see what happens.

 

welcome pisigma. u'll get lots more help in the 2nd gen section. also check out the SE section when ur able to.

 

I've apparently misplaced my multimeter so I'll be going out to buy it later on today after tightening up that ground and seeing how that works out.

And I plan on visiting the 2nd gen section, but I apparently need to get my posts up before that, haha. I just got my RX7 a few months ago and have been loving it ever since, so I expect I'll be around here for a while. Especially considering the response times here... Excellent forum for an older car. Then again I suppose it is for an excellent car.

 

BTW: The needles for the tachometer can get sticky, especially since they are older cars and since it's been very cold recently/ (At least in my area)

Confirm that you do have spark to the two upper (Trailing) spark plugs.

 

Cleaned up the ground, and now the Tachometer and starter are working wonderfully. I also checked for spark just in case, and there's still spark to be had. Unfortunately, I seem to have done something to the oil gauge in the process, haha.

I'll be checking the fuse as soon as I grab a diagram just in case it blew with the messed up ground, but is there anything I might should look for?

 

Oil gauge is fed by the sensor under the oil filter. It looks like a mushroom.

If you're in the area, it's easy to knock loose the wire that goes to it. That wire also tends to get caked with oil and dirt. Cleaner is highly recommended.