My freind car toyota vios 1.3 has a high rpm when hot ranges from 1300-1500, and the idle is fluctuating.what seems the problem?

NOT told TOO HIGH OR TOO LOW, and what the RPM now.????
800 RPM hot is par for hot idle.
in USA all are cars 1988 up EFI are controlled by ECU and not the humans did with carbs in the good old days/ by LAW here.

HOT idle RPM or cold IDLE RPM.??? or both are wrong.
not told that. and is key to any cure for sure.

Toyota glanza ep91 turbo , manual

what country is it. sold to first. (market export)
1989 to /96 car?
I bet this is the real name, fully]
Toyota Starlet 1.3 Glanza V Turbo (EP91, Japan)

glanza V was powered by the turbocharged 1331 cc 4E-FTE
ECU controls actual turbo and injection rates and more.
and sold to
Japanese market, although some used private imports made their way to the UK, New Zealand, and many other right-hand drive markets.
most cars but gee 1989/96 are very old cars.
had 2 idle speed controller. (this is pure experience not your car that the USA does not have)
IAC (thermal controlled idle (coolant temp.) only
ISC (ECU control hot idle above 65C coolant temp)
this how all ours worked here, 1986 to 2000, then the ISC took over all idle controls.)
no 2 engines use same controls,
on some old cars high idle hot is caused by these factors.
1: coolant never gets to 82c(bad thermostat)
2: vacuum leaks.
3:IAC bad or ISC , clogged up, and jamming/sticking
3: ECU is stuck in limphome, idle controls suspended.
4: on our cars the EPA dictates IDLE and has no screw to set.
5: TV plate gummed up and sticks (throttle valve)

the best answer is to first buy the service manual
and read ISC page (idle speed controls) ECU controlled.
read IAC Idle Air controller. page. water temp controlled.

Plz Check Camshaft And Crankshaft Position Sensors

You should remove inspect and clean the idle control valve on the throttle body. This can become clogged over time, or the motor itself can become worn and may need replacing.

fans arnt coming on check your relay fuses and go from there

May be a cooling sensor issue . If you can hook a scan tool to it and watch the coolant temp pid while idling high it may show a fluctuating reading .

A high idle is caused by either a massive vacuum leak or a sticking idle speed control valve. I would think you have a vacuum leak, use a can of carb spray and shot around the top[ of the engine, if you hit a leak the engine will sound different, repair as needed.

vacume leaks will cause that listen around for any hissing or whistling and fix any if found.

I would check for a broken vaccuum hose . A vaccuum leak will raise the idle considerablly.

check map senser if thats good check your fuel filter

Hi
your problem seems very easy :) hope this one work with your envoy. Just buy AC DELCO carburetor tune-up conditioner.

How you use it: engine running , AC off please

1. detached the big black airflow hose which is attached in the mannifold of the engine block.

2. ask your friend to step on the gas pedal and set the rpm steady in 2000 rpm only.

3. then spray vigorously in 8 seconds the inside circle opening of mannifold while your friend steady step on gas pedal with steady 2000 RPM only.

4. after you spray, let your freind continue on gas pedal with 2000 rpm for 15 more seconds.

5. attached back the airflow big black hose to the manifold and you are ready to roll with your AC on.

if this one doesnt work, please scan your envoy by scanner called TECH II. and find out.