I tried to install an APC tach over the weekend on my 2001 RS Eclipse (2.4L engine) but with mild success. I got the power and lighting to work fine. I ran the green tach wire from the APC tach to the black\blue wire on the right coil on top of the engine. When I start my car and rev it, I only display half of what the actual rev is. In other words, when I rev the car to 4000 RPMs my APC tach only shows 2000 RPMs. I noticed there is another coil on the left side of the engine with a white\green wire and black\red wire. Am I suppose to use the one green wire from the APC tach to tap into both of the coils, or should I only be on one of the coils? Maybe I just have the wrong wire? My only other choice of wire on the right coil other than the ground wire is a black\red wire. I have no idea what to do, but as it is the new tach is worthless if it only shows me half of what I am actually rev'ing! Any help would be appreciated. Thanks!
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Is there any type of cylinder setting on the tach? Whatever it is set at cut it in half. If it is set to 4 cylinder then cut it down to 2. If its set at 8 cut it to 4. This will make it right.
Thanks for the reply Player69. Yeah, this tach does have a cylinder setting, which is set at 4, unfortunately it doesn't have a setting for 2. My only options are 4,6, and 8. Any other suggestions?
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Does the car have a factory tach? Perhaps you could get it at the back of the instrument cluster and it might be a 4cyl reading.
Yeah it does and I thought about doing that but wasn't sure how to go about it. I was actually more scared about doing something wrong if I tried it that way. I guess I'll have to look into that! Thanks!
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You will need to find a wiring diagram and find out which wire supplies the tach. You can also get a digital multimeter, hook black to ground and set meter to check AC Voltage. Has to be ac voltage no dc. Then probe the wires at the instrumen cluster and look one that has voltage that increased with RPM. Good luck!
Yeah that sounds good, I'll have to get a multimeter I guess and try that. Thanks for all the help.
PS. I did look at a wiring diagram and it tells you that the tach wires are the ones on the coil on top of the engine. I have a choice between the black\red or white\green.
Thanks again!
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