Check that you connected the tach wire correctly. Grounding the tach signal wire will cause a no-spark condition.

Double checked connections. Even connected spare tach. Both of the tachs are/were good. Still no start.

Tach or your hookup of the tach is questionable. Your signal wire is making it to ground some how. As stated before that will not allow the spark to work.

Does the GEN warning light in the combo gauge have to be connected correctly for the car to start?

Should it start if I disconnect the tach?

I think so as long as the wire is not grounded on the engine side. Did you check your fuses just to be sure you didn't pop one? Check your combo gauge wiring as well if you swapped that out.

The tach does not inhibit the engine from running, so yes, the engine can run w/o the tach connected.

Does the fuel pump run when you turn the key on? If you have FI, the FP will run for 2 seconds when you turn the key on.

You could always disconnect the tach at the ignition coil too. It's the black/purple wire. Then try starting the engine.

I have been having the same issue with my tach. The only way I can start the car and run it is if if the purple and black wire at the ignition coil is unplugged. If the car is started and I plug this wire to the coil, she immediately dies and will not start. I have just been running without the tach until I could trace the issue.

If you plug in the tach wire at the coil and the car dies, then that wire is connecting to chassis ground.

Could be it's plugged in the wrong place up front, could be that it has chafed to ground somewhere along the way. Could be the tach has failed internally.

The same thing happened on my 914. I found the tach wire in the engine wire harness was shorting out. I measured the resistance of the tach wire at the coil and when I unplugged the engine harness from the relay board and the short remained. I ran a new wire from the tach to the relay board and all was good.

I am figuring this is probably the case. What I intend to do is run new wire directly from the coil to the tach and see if the this will fix the issue and with a new ground and go from there. I don't know if the original poster of the thread has this issue as well but my gas gauge does not work either and I figure they share a bad wire between the 2 gauges.

I am hoping that is the case with mine.

An update. I triple checked all the gauge connections. Here is what's happening: The fuel pump activates when I turn the key, it has spark at the plugs, a refurbished ECU, a 123 distributor, and will turn over and start on starter fluid BUT it has no pulse at the injectors with a noid light. Could the ignition switch be a cause? It won't lock the wheel and never seemed to operate smoothly when turning the key.

what year car what version of engine, what EFI is it running?

Then at least we will have a clear picture to help you figure this out.

D-Jet 1.7L and 2.0L use trigger points in the base of the distributor to tell the fuel injectors when to squirt gas towards the valves.

Are the three pair of injector grounds connected?

D jet 2.0 with 123 distributor. 3 trigger point wires connected.

So...we're talking about all this other stuff but I have to go back to your topic title and first post...

Is **ALL** you did was swap the gauges, and now it won't start?

If so, swap it all back, see if it starts.

If not then you need to tell us what else you did.

You said it will start if you spray starting fluid into the intake, so the ignition is working. Leave it alone for now.

Jeff is trying to get you to check the injection ground point on the engine case.

The grounds are not the same as the connections for the trigger points. Look at the top of the enigne case, on the right side, just to the rear and below the intake plenum. There should be a 3 spade ground connector held on by the case through bolt. Check to make sure there are 3 connections there.. 2 should each have a pair of white wires connected together, and one should have a single white wire. If any of them are disconnected, then the car will not have an injector pulse.

Let us know what you find.

Clay

Two were a little loose but all were connected.