Just wanna go ahead and say howdy to everybody. finally got found by a 77 280 and i love it. been sittin 16 years got the old girl home and one week later got to go for the first ride. thought all the hard work was finished since its running smoth as butter........WRONG! having a heck of a time with tachometer issues. have been cruizin forums for days hopin that my first post wouldnt be a help wanted ad. but, the 76 and 77 wiring diagrams i have are diff colors than my tach wirin which is drivin me nuts. so, hello , great forum ,and please help all in one.

:classic:

directions please,

I suggest describing wiring colors that you DO have. Could be that PO could have replaced OE tach and hacked it. Tach relates to coil, etc. Look around for splices, bastard wiring/extraneous wires. Detailed and informative questions will yield detailed and helpful answers/suggestions.

Pardon my poor manners...

Welcome!

,im gonna love this place, i can already tell. the electrical system seems to have never been tampered with, the car sat 16 yrs before when i got it. its a 77 and the pigtail for tach is....red/blk,g,blk,white/red,white/blk,red/blu,g/white.its not the first time ive seen a car or a tach but this little deal has really got me puzzled. and i hope i posted in the right place.

What are the "issues"? The needle doesn't move or it's jumping around or it hangs at high RPM? These are fairly typical tachometer problems.

The wire most likely to get disturbed outside of the dash area, is the blue wire from the coil. Is the car still running the original EFI? And stock ignition system? All important factors.

yes all original equipment from all appearances, it was sticking like.....would move really slowly or not at all stayed at last rpm when trnd off.and what year the pigtail is exactly.

I just came to welcome you to the club! I know nothing about how to fix a tach. Mine jumps around from time to time as well. I have no idea why.

thanks just the same,so far really cool forum .

Sounds like it might be a mechanical issue inside the tach. Have you tired removing it from the dash to see if there are any mud dobber nests in the guts of the tach?

yup, and as bad as i hate to say...I broke the damn thing removing the case. Even tried another tach, it didnt work...so I am wonderin about the pigtail, wire colors dnt match 76 or 77 wiring diagram . mines a 77. i bruoght it back from a 16 year slumber, and ive only been able to drive around the neighborhood(live out in the country) . I have OCD when it comes to knowing what the motor is doing, all the gauges seem to be working properly other than the tach, and temp guage needs a new sending unit soooooo. #1- what gives with the pig tail, #2- should i just go ahead and get aftermarket guages.

ATTN: for those members that require gramatically perfect spelling and acurate use of the english language, please look over me i get excited tlkn about cars and kinda jump around and ramble uncontrollably .

Welcome, and welcome also to the blissful money pits that are z cars A first recommendation is two good sources for factory service manuals. Banzaii Motorworks is a great place to find the actual books, and xenonS30.com is a great place to find the manuals online. As you're realizing now, a 35-year-old wiring system that appears unmolested does not equal a properly functional system. I've got two fuses pulled from my own z's fuse box (horn and parking lights) because, despite proper function, they each have a short somewhere that leeches current slowly and steadily.

And yes, this is by far the best place on the web for support and real technical feedback on these cars.