someone told me they are someone told me they arent

 

nope the 88-89 harness is different than the 90-91. and i mean the whole harness dash, lights,engine. thats why you cant put a 88 cluster on a 91. found out the hard way.

 

That sucks, but agree with you on the 2 harnesses being different.

 

hey-hey.
which harnesses are you talking about? If engine harnesses, then 88 is different, while 89-91 are interexchangeable.

88-91 might have a single difference - some have fast idle valve plug, some don't, but this difference does not affect driveability, and does not throw a code. So for all practical purposes, 89-91 engine harnesses are the same.

 

the 89-91 engine harness are the same its the sub harness in the 88 that is different i belive

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nikitad &raquo;</TD></TR><TR><TD CLASS="quote">hey-hey.
which harnesses are you talking about? If engine harnesses, then 88 is different, while 89-91 are interexchangeable.

88-91 might have a single difference - some have fast idle valve plug, some don't, but this difference does not affect driveability, and does not throw a code. So for all practical purposes, 89-91 engine harnesses are the same.</TD></TR></TABLE>
correct - the 88 didn't have Fast Idle Control Valve - the connector where it plugs into the chassis harness on the driver's side is square 6 wire connector on the 88 and round 8 wire connector on 89-91 - 88 engine harness will only plug right into 88 chassis harness

 

I gotta correct myself. "some of the 89-91" don't have the fast idle plug either. They both have a round plug, but FICV wires are not there. It desn't make a real difference though.