My tach is reading about 700 rpm higher than the actual engine speed, give or take. I know this because I can plug a handheld gauge directly into the distributor. I did a search, and the only think I found was something vague about a "tach filter". I dont know what this is or if my car even has one. Anyone know how to fix this?


While I'm on the subject of gauges, is there any way I can lube up my speedo cable? Speedo's bouncing +- 10mph and getting on my nerves.

 

Non-tech answer on speedo - replace the cable. Mine went bad at 85k on my '87 T/A and did the same thing. The outer part of the cable (sheathing?) had worn through.

Not sure on the tach, sorry!

 

Neither the 84 or 85 T/A's had the tach filter on them, carbed or otherwise. The camaro's however did have them.

 

You have to pull out the cable from the top at the guage end. Remove it, clean it completely and relube it. When you reinstall it slide it back into the housing and slowly turn it back and forth until you feel it drop into the drive gear. The tach reading is usually caused by the capacitor(s) usually the polarized electrolytic type changing value. Any electronic repair shop if you do a little schmoozing will probably do it for less than ten bucks.

 

would the 8k tach out of the 84 parts car work in the 85, where there is currently a 6k? that would make life simple if it did.