2008 Lincoln Mkz. Why does it overheat periodically?
vast reasons there are, 3.5L engine?
leaks only hot means explosive stream and 265degree hot water blasting out of reservoir cap>?????
yes it needs flush any car that old never serviced ever.
first we test the front fans. that must com on at a stop signal
In july summer, the kick only at 220F, or AC turned on.
they must.
F28 fuse blown? depends on engine not told but 60 or 80amp fuse here. there were 3 fan systems that year,
one is full variable speed fan, and the fan is smart fan.
costly. the PCM modulates that fan with 1 wire, for speed.
PCM decides it all.
no VIN TOLD so no magic. answers.
here is my overheat list,
my short list (generic for all gas engines modern water cooled)
proof: first: aka as evidence, doing tests and inspections.
see steam, blasting out? that is overheating. ?'
Steam under hood or steam at rear of exhaust tail pipe
or the dash gauge engine heat, lies or shows too hot, ?
coolant blasting up violently from Radiator overflow tank, or at rad cap.
dash gauge goes past 260F degrees? PID scans OBD2, ECT same.?
engine Pings (deep rattle inside engine) bad this is for the engine.
Engine power weaker.(now)
seam blasting out of hoses or RAD core or its side tanks or steam blasting at the sides of the head gasket (from warped head)
LEAKS, (coolant) or using water only for coolant , never do that.
Leaks to the ground,
leaks squirting from hoses. Use no sealants on hoses.
RAD core leaks or its side tanks cracked and leaking.
Coolant drips off head to block junction (gasket bad) seen.
All coolant leaks must first be found and corrected.
Leaks of coolant to front passengers toes. heater core bad or hose to it leak.
more leaks.
freeze plugs on sides of engine leak coolant to the ground, seen
see water on the ground parked running hot. (idling for up to 30mins)
see water at front passengers feet/toes.(heater core/hoses shot) leaking, look carefully.
Coolant found in ENGINE OIL PAN, and looks like chocolate milk shake.
Same goes for Coolant found in the A/T ATF oil pan. same look. as above (milky)
Causes: In no order.,but gee simple things first.
Fan belt fell off or slips/loose frayed,etc.. or bad tension-er
some folks put the serp belt on wrongly routed and pump turns backwards (FAIL it will)
Thermostat is bad at 7 years old. (common as nails)
Running mud for coolant? ;-) for 20 years, why?
Fans on front of engine or on RAD dead. or bad fan relays or controls .electric fans turn on at 220F. (par) fuses blown to them.
a bad radiator cap and leaks, (a cheap easy fix)$5?
Dead bugs packed in front Radiator and or A/C condenser core.(front end of car)
the coolant in the RAD cores or engine block water jackets look like RED MUD,(abuse)(flush it out) do a full drain flush and refill with spec coolant.
also mixing 2 kinds of coolant in 1 engine the coolant looks like JELLO , GEL up horror.
Flush it all out and use only Prestone "ALL Vehicles" 50% , do not mix brands or types.
Bad Radiator.(tubes inside clogged up) IR thermal gun test easy find, we check all tubes end to end
if one tube or more does not act like the others , those tubes are clogged
or more oddly places to leak:
leaks caused by any bad gaskets that can leak coolant. (lower intake manifold leaks.)
leaks coolant to engine oil pan (looks like chocolate milk-shake)(dip sticked or drained)
Same thing coolant lands in the A/T tranny ATF oil pan. (bad radiator tranny cooler)
some engine,this leak here runs down front or rear of engine , intake gasket bad.
Engine bolts snapped.and leaks coolant, pump, etc.
Bad water pump, or wrong one installed (wrong direction of belt put on wrong)
the pump front shaft has a weep hole(must not leak) and a gasket to leak.(new pump and gasket time)the pump impeller of steel rusted to nothing,.oops
evidence pump is bad? 5 ways to fail it can. (bearings /seal / impeller/gasket can fail or snapped bolts)FAN BELT MISSING,OR WAY LOOSE.
Other things on many older engines can fail, water heated items like IAC or TB heater pipes , the larger hoses not vacuum need to be checked to all things in the path that can leak coolant.
The water hoses seen and felt too get hot , all can leak.
other causes."
the Radiator IS BAD, both clogged or leaking.
Engine block cracked
Engine HEAD cracked or warped, or bad head gasket. ICE damage running only water for coolant.
Engine: all water jackets full of mud (rusted up mess)
Overheated heads too much and they warp and the gasket fails.
Main intake pipe heater leaking, older cars had this. 1980 to 1996 hot air induction tech.
not running 50% antifreeze coolant, or over 5 years old. if it looks bad it is.
Old coolant turns ACIDIC. and eats things up, and fails.
one top cause of overheating is not burping the coolant loop of all air.
This takes skills due to vast engines use, I burp the highest point
the Thermostat bleed old or jiggle pin must be UP> or it fails.
False signs of overheating the dash gauge lies, because the ECT is bad or some bad boy put the wrong ECT sensor there. Oops that is very painful...
ECT fails of coolant is too low and only air lands no the ECT sensor.
LEGEND:
TB = THROTTLE BODY
RAD= ENGINE AND TRANS RADIATOR COOLER.
IAC, IDLE AIR CONTROLLER VALVE
ISC ,Idle speed controller.
ICE = FROZEN WATER.
OBD2, The USA on board diagnostic port, 1996 up, scan with a real scan tool is best.
PID - as scan mode to see live sensor data. using the tool. scan the ECT first.
IR gun is , tool that measures surface temperatures, and no burnt hands.Infra RED
Coolant is 50% antifreeze and anti-boil 265F rated. do not mix brands, ever.
Drain flush and fill and burp out all air first.
Do not run any under-filled engine or risk warping the cylinder heads or worse.
best way to find a leak !
is hood up, let engine idle for 30 full minutes or more and you will see the leak.
Watch out for leaks that squirt to places no bad. oops.
or effects of gravity and windage blowing coolant to things not bad.