Crazy Gauge

[rad73]

1998 Suzuki Sidekick Sport 1.8
I started getting random overheating spikes and now it is constant. I used IR temp gun and the engine is not over heating. Replaced both the temp gauge sensor and the ECM sensor. Using TorqueLite app with OBDII and it says the engine is over heating????? Gun reads 190-200 at the sensors at the back of the head??????? Scan tool says 270+????? Needle on gauge is in the red??

[fixkick]

the j18 engine uses the hotter , newer thermostat (EPA rules) 200f , so is normal'
that is correct 270f IS overheated, (but the gun tells you it is no so is not,
but did you point the gun to the rear of heat outlet housing (ECT is mounted there)
scan tool does not lie, IT reads ECT reading, tells me the ECT bad. (rear of head) unless ect is bad you installe the wrong sensor as we see you did, (Ect IS not THE AC OVERHEAT SWITCH YOU BOUGHT)
THE ECT IS ON BACK OF HEAD TOP, AND HAS 3PINS, FOR SURE.
ect bad. STILL
also on the very tricky engine, (not this time or case) is that small hows from rear of water pump to the rear of clogs the thermostat goes WILD.
a very nasty very difficult problem to diagnose, just heads up, on this j18
see my J18 photos here.
http://www.fixkick.com/overheating.html

also , watch out for wrong ECT (OMG I NAILED THIS BINGO BUYING ON EBAY)
most stores (bad) sell G16 thermostat or ECT as soon as sidekick is said, a real pain in the ash can this is. J18 is the correct ECT
your VIN code is unique for j18,,,, and if they dont ask that ,bingo all parts are wrong. for sure.
btw rockauto.com asks for.r j18 sport. (but they dont ask for G16a or G16b so then get that wrong)

1998 Suzuki Sidekick Sport 1.8
I started getting random overheating spikes and now it is constant. I used IR temp gun and the engine is not over heating. Replaced both the temp gauge sensor and the ECM sensor. Using TorqueLite app with OBDII and it says the engine is over heating????? Gun reads 190-200 at the sensors at the back of the head??????? Scan tool says 270+????? Needle on gauge is in the red??

[fixkick]

IIRC,: the J18 has dual sensor rear of head outlet housing
here is SMP view
https://www.rockauto.com/en/moreinfo.php...13&jsn=346

smp match
https://ecatalog.smpcorp.com/STD/#/vehic...423?type=s

[rad73]

First, Thank you for taking the time to reply to my problem. I did replace the ECM temp sensor and it appears to be the correct one. https://www.ebay.com/itm/New-Coolant-Tem...2749.l2649. I think I will remove the stat and run it to see what readings I get. That way it would be impossible for it to get hot at all. Weak water pump?

[fixkick]

omg that is the wrong sensor with 2 pins, you see the harness connector has 3 pins, no way would that fit 2 pin toyota sensor
ebay sucks for parts, that part selector there and in spanish is a pack of lies, whats new there, same o same o.
no, that dweeb seller lied it the AC temp switch and has nothing to do with ECT at all.. ECT is only fitting rear of head only .

many suzuki G16b were called sports, in other countries, and are not J18 engines. did you know that, why not buy parts in N.America where they match and fit.
The J18 only has this sensor behind the head, no sport (true with wide frame and J18) has any ECT on front of engines as G16s all have.
the J18 is 3 pins, the J16 is 2,
no only that but the RTC thermal resistor inside is totally different..


if you had a good ECT there, and dont the below is next. if scan tool shows overheating.
The EFI will never like running thermstat free, rich a pig,
why not put a new thermostat it , when it gets hot it opens wide, there is never a reason to run with no stat.
does it overheat driving fast but only at stop signs."
if only stopped, overheat the fan clutch is bad.

if it overheats parked or moving fast 40mph is fast
then the pump is bad (or the belt loose)
or RAD tubes clogged
gee that IR fun is amazing to test for bad rad tubes, super easy.
how can it overheat to 270F and not steam flying out the rad side overflow tank,,, how odd is that,

IR gun RAD test
get engine fully hot, but not overheated
then at idle
see top of rAD tank, this is the hot end. top
then with IR gun scan all tubes top to bottom
if all are 200f , on top
and all are 50 less at near bottom then the tubes are ok
if one or more tubes shows 200 on both ends, those tubes are clogged.
practices on a good car. learn this skill

[fixkick]

ahhhhhhh i see your confustion
the sensor you bought is for AC thermal switch only, see that word switch?

Do not confuse the AC temperature switch with ECT the former is just switch
the ect only fits the the rear of the head and has 3 pins, and is on the exit rear head housing.. that hottest place for coolant. exiting head.

lets use advance auto parts
this is the correct sensor
https://shop.advanceautoparts.com/p/beck...URE+SENSOR

the AC switch is not a sensor, no sensor is a switch .
2pins and is not a sensor
https://shop.advanceautoparts.com/p/fact...URE+SENSOR


see?


if the engine truly overheats,no proof yet, the IR Gun said NO.
consider this fact: the ect defective will never make the engine every overheat.
the 2nd set of pins in the ECT is crude, dash guage sensor, and that can not cause overheating ever, sure it lies to the driver, only
symptoms of overheating are
sure dash gauge reads too high but your sensor was never replaced.
the engine pings
the loss of power
the rad side tank blowA steam or huge blows of hot water so violent the side tank (overflow) WILL BLOW OFF THE TANK
CEL LAMP GOWS AND SCANS SHOW THE DTC FOR OVERHEATING;
THE SCAN TOOL READS THE ECT ACCURATE SIDE OF THE 2 SENSORS IN SIDE OF THE ECT.

the first thing to check are
fan belt missing or slipping
then check water levels and 50% consentration of antifreeze never ever run pure water.
next a new thermostat, . and full flush on such and old car.
if it only over heats parked, (pump ,rad or fan dead or weak) but is ok moving fast, blame fan.

[fixkick]

THE ECT ON THIS ENGINE ONLY HAS 2 SENSORS INSIDE AND 3 PINS,
1-ECT SENSOR GRAY-YELLOW AND GRAY-RED WIRES,
2=THE DASH GAUGE TEMPERATURE SENSOR
IT'S NOT CHEAP LIKE THE $7 AC SWITCH, THAT IS VERY SIMPLE INSIDE
NOR ARE THEY THE SAME. NOT BY A MILE.
J18 ANSWERS.

[rad73]

Ok. I order this temp sensor and this thermostat. I really think that the temp sensor is the problem. Thank you for your help. I will update you when the parts come in.

[fixkick]

yes , the Ect IS really 2 sensors in one, thus the 3pins
either can fail.
the IG gun if used correctly proves the engine is NOT overheated for sure point to 3 places.
the rear ECT housing on rear of j18 head. (front G16)
the top rad tank will be hottest
the bottom 50f less hot, 150 is common there, if fan works, and the fan must work or all cars overheat parked.

my guess is you bougth the AC thermal switch thinking it is ECT, but the sellers really are not too clear on this.some even lie. for sure all junk sold on fleabay

to buy on fleabay
buy by brand (top) and part number,
then look the makers catalog on line and read the page for you car, and engine, matching that to engine.

SMP is top good brand and choice
as is ACdelco
and BECK
NTK = same co. as NGK spark plugs. top brand last.
I always buy by top brands, non name brands are very risky. (wasted labor or , vacation panic? wasted cash, wasted do over.)

https://www.rockauto.com/en/catalog/suzu...ensor,4748

[fixkick]

see IR gun test2
180f stat (for 200 add 20)
my thermal gram page, nice tool and amazing find clogged rad tubes, with zero real work.
http://www.fixkick.com/Cooling-engine/therm-o-gram.html