A/C compressors can be rebuilt, exchanged for equivalent re-manufactured units, or purchased new. While new is more expensive than used, we recommend new since it is difficult to determine the quality of a used compressor by simple inspection. Installing a used compressor only to find it is defective is not a pleasant exercise.
In a nutshell, the compressors which came stock with the Fiero are as follows:
'84-85 2.5L ---- DA6 or HR6HE '86 2.5L ---- V5 '87-88 2.5L ---- V5 '85-87 2.8L ---- DA6 '88 2.8L ---- HR6
Here is what they look like, although we aren't sure the pulley is correct on the V5:
When purchasing a replacement compressor you will find that parts stores may not provide the exact unit that originally came with the Fiero because technology has improved, some parts are no longer available, and because of the government mandate to use R134-a refrigerant. Part numbers for replacement compressors are as follows:
'84-85 2.5L ---- GM 1136465 or AC Delco 15-20241 '86 2.5L ---- GM 1135192 or AC Delco 15-20084 '87-88 2.5L ---- GM 1135191 or AC Delco 15-20085 '85-88 2.8L ---- GM 1136478 or AC Delco 15-20248
Note that '84-85 Fieros were fitted with two different compressors in their lifetime, the DA6 with a 5.125" pulley and the HR6HE with a 5.75" pulley. The DA6 is obsolete. If you are replacing an old DA6, use the HR6 which is the part number shown above.
A good writeup with information on the compressor high/low pressure switches can be found at this link: http://www.fiero.nl/forum/Forum2/HTML/117640.html
'84-85 2.5L w/5.75" Pulley: The compressor for this Fiero is the HR6HE (Harrison Redesigned High Efficiency 6 cylinder). It is 9.3" long, 4.6" diameter and weighs 12.6 pounds. The vehicles listed below had the HR6HE as well as other compressor options, so finding a used compressor may not be as simple as finding a potential donor vehicle. In general, an exact replacement may not be necessary to achieve adequate cooling. If a compressor will fit it may be worth trying.
Pontiac Astro '85-86 2.5L Chevy Blazer S10/Jimmy S15 '85-86 2.5L Camaro '83-85 2.5L Firebird '83-85 2.5L Chevy S10/S15/Sonoma '85-86 2.5L GM Safari '85-86 2.5L
'84-85 w/5.125" Pulley: This compressor is the DA6, unique to the '84-85 Fiero. It came with either one or two switches. If replacement is necessary the AC Delco unit listed above is suggested. In general, an exact replacement may not be necessary to achieve adequate cooling. If a compressor will fit it may be worth trying.
'87-88 2.5L: This compressor is the GM V5 and is unique to the '87-88 2.5L Fiero. It has a 4.29" pulley (some sources say 4.33") and one switch in the rear of the compressor. The following compressors may be worth trying in the '87-88 2.5L Fiero by changing the pulley, clutch, and switches as necessary. Some of the donor compressors may have a plug in place of one switch. In general, an exact replacement may not be necessary to achieve adequate cooling. If a compressor will fit it may be worth trying.
If you want to convert the V5 compressor to R134a, note that it has a control valve on the side which should be changed to suit the new refrigerant. The valve can be obtained from a number of sources, notable from A/Ction Air (action-ac.com), their part number 31-55302.
Chevy Beretta '87-89 2.0L Chevy Beretta '90-91 2.2L Chevy Cavalier '87-89 2.0L Chevy Cavalier '90-91 2.2L O-ring on suction port Buick Century '93 2.2L Olds Ciera '93 2.2L Chevy Corsica '87-89 2.0L Olds Firenza '87 2.0L w/ OHC Olds Firenza '88 w/o OHC Buick Skyhawk '87-88 w/o OHC Pontiac Tempest '87-89 2.0L Pontiac Tempest '90-91 2.2L
'85-87 2.8L: There is some confusion on our part about the compressor for these Fieros. The Hollander manuals say the compressor is the HR6HE (Harrison Redesigned High Efficiency 6 cylinder). The Pontiac "22P" manual refers to the compressor as the Harrison "DA6" (Downsized Axial 6 cylinder) and we believe the latter to be correct for the factory-installed unit. Our research indicates the exterior of the two compressors is identical. Our belief is the HR6HE is a recommended upgrade. The DA6 compressor has two electrical connections on the back end. Note that the DA6 is not considered a good candidate for conversion to R134-a refrigerant, probably because of the higher pressures encountered.
The vehicles listed below are from Hollander and are in reference to the HR6HE compressor. While the compressors originally in the cars below were probably not the HR6HE, odds are they had the same original compressor as the Fiero. Finding a compressor may not be as simple as finding a potential donor vehicle. In general, an exact replacement may not be necessary to achieve adequate cooling. If a compressor will fit it may be worth trying. Compressors from other Fieros are good candidates for swaps, but brackets my have to be transferred along with the compressor.
Pontiac Astro '85-86 2.5L Chevy Blazer S10/Jimmy S15 '85-86 2.5L Camaro '83-85 2.5L Firebird '83-85 2.5L GMC S10/S15/Sonoma '85-86 2.5L GMC Safari '85-86 2.5L
'88 2.8L: The compressor for this Fiero is the Harrison HR6 (Harrison Redesigned internally DA6) with a 5.4" pulley. It is physically identical to the DA6 with two electrical connections. It is a good candidate for conversion to R134-a refrigerant. The AC Delco part number for the current replacement compressor is shown above. Cars which had the same original compressor are:
Pontiac Grand Am '87-89 2.0L Buick Skyhawk '86 1.8L VIN "J" (8th digit) Buick Skyhawk '87 OHC, turbocharged Pontiac Sunbird '86-89 turbocharged
A/C Dryer (Accumulator), '84: We have no GM part number for the '84 dryer but have been advised by Fiero owner Bill Strickland that AutoZone and Parts America carry a replacement. It is Ready-Aire 4370N. The '84 dryer is the same size and appearance as later years. However the inlet and outlet lines are 180 degrees apart and the low pressure cutout port is in the location of the main inlet for dryers used in '85-88. The dryer is available at AutoZone for $12 as of August 2008.
A/C Dryer (Accumulator), '85-88: The original GM part number for the '85-88 dryer is 3059313 but this has been superceded by part number 2724666. An aftermarket version is Factory Air/Four Seasons part number 33181 typically available at Pep Boys and similar parts stores. AC Delco part numbers which also work are 15-1392 and 15-1670. AutoZone and Parts America have a replacement under their part number 4392N by Ready-Aire. Old dryers should not be re-used since their ability to remove moisture is depleted.