can i use the dash wiring from a 89 cougar on my 88 cougar as long as they both have the same motor?? none of the junkyards around me have any 88s they have 87s but only 5.0s and i need a 3.8
No.
Totally different harnesses.
is the 88 3.8 the only wiring i can use?
For the dash? No, you can use any 87-88 T-Bird or Cougar harness (and probably the 85-86 as well), though the TC one will be more complicated and will include things you don't need.
Somebody else mentioned a good point in one of your (many) other threads on the subject: You will need a harness with similar options to the car you have. For example you'll need one from a base cluster car if yours has the base cluster. If you can't find the correct harness, you should still be able to make it work by using some parts of your existing one and repinning connectors where neccessary.
In future, please be a little more specific with your thread titles.
ok i found a 87 thunderbird at a junkyard i can go pull it but i dont think it has the motor in it how can i tell if its a 3.8 motor?
You can tell by the vin number.....it's in another thread you started too......heres a great link....
http://http://www.coolcats.net/tech/reference/vincode.html (http://"http://http://www.coolcats.net/tech/reference/vincode.html")
darn dood, how many threads on this,,:D
leme see if i can repeat what i said on the other one,,lol
your options..........
engine harness from 88 (cause its a pretty unique year)
or
engine harness from most any car that had the same motor. (ie- with the upper intake).
or
You could also find an mn12 bird/cat with the same motor and use the engine harness.
or
engine harness from an 84-87 car which is CFI. The harness is pretty much the same and the eec only uses 2 pins for injectors on both the "SEFI" 3.8 as well as the CFI 3.8.
Dash harness,,,
you have to hunt down a coug/bird from the 85-88 years.
visual give away is the 3.8 had the battery on the pass side.
next is verify vin
next .......
get the harness.