1988 Cadillac EL Dorado ENGINE COOLING FAN

RUDDYMEN

MEMBER
1988 CADILLAC ELDORADO
4.5L
V8
FWD
AUTOMATIC
174,000 MILES

WHEN IDLING THE ENGINE WILL HEAT UP AFTER ABOUT 10 MINUTES COOLING FAN DOES NOT COME ON. CAR RUNS COOL DRIVING. TEMP REACHESOVER 220 IDLING BUT ONLY RUNS ABOUT 150 GOIN DOWN THE RD. IVE REPLACED HEAT SENSOR ON THERMOSTAT AND I HAVE TESTED THE FAN ITS SELF WITH A JUMPER WIRE THE FAN RUNS. IF I START THE CAR AND UNPLUG THE THERMOSTAT SENSOR THE FAN RUNS WHEN I PLUG IT BACK UP IT STOPS. IVE TRIED THE RELAYS IN FUSE COMPARTMENT BY REPLACING NO LUCK. WHAT NOW? AC COMPRESSOR DOES NOT WORK WOULD THAT HAVE ANYTHING TO DO WITH IT.

7 Replies

HMAC300

MECHANIC
48,601 POSTS

Have the cooling system pressure checked for an internal leak like a head gasket. These were beasts for eating those.

Was this

answer

helpful?

Yes

Saturday, January 18th, 2014 AT 6:46 AM

RUDDYMEN

MEMBER
9 POSTS

THERE ARE NO LEAKS IN THE HEAD GASKET HOLDS PRESSURE FINE. NO OIL IN WATER OR WATER IN OIL BOTH CLEAN. NO STEAM IN EXHAUST.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Saturday, January 18th, 2014 AT 11:46 AM

HMAC300

MECHANIC
48,601 POSTS

Check the things in pic that I have pointed out. This could be a module problem however. Running at 150 soundsl like it has a to low of atemp thermostat it should be a 195 stat. The sensor you should have replaced is by the dist. So just check to seeif power is going to that. It can also be a fusible link which should have power on both sides if the orange wire has power to the one module pointed out and nothing comes out then it's probably a module problem as well as a body module problem. So scanning with a tech 1 in this case may seriously be required to fix. It.

Images (Click to make bigger)

Was this

answer

helpful?

Yes

Saturday, January 18th, 2014 AT 12:45 PM

RUDDYMEN

MEMBER
9 POSTS

THANKS I WILL CHECK THESE AND SEEHAT I COME UP WITH.

Was this

answer

helpful?

Yes

-1

Saturday, January 18th, 2014 AT 3:21 PM

RUDDYMEN

MEMBER
9 POSTS

GETTING POWER TO RELAYS, ALT. WIRE, NO POWER COMING OUT OF THE MODULE IN FRONT OF RADIATOR. WHEN IGN. IS ON I CAN UNPLUG THE SMALL BACK CONNECTOR ON LEFT SIDE OF BOX IN FRONT OF RADIATOR AND THE RIGHT FAN WILL RUN. WHEN I UNPLUG THE THERMOSTATE SENSOR THE NEW ONE I REPLACED BY THE DIST. CAP THE LEFT FAN WILL RUN. WHEN THEY ARE PLUGGED BACK UP FANS STOP. BOX IN FRONT OF RADIATOR O.E.M. # IS 1641400 COULD BOX BE BAD.