Question about 1990 Geo Prizm

1 Answer

No heat replaced radiator, water pump and thermostat,still no heat, control valve works good , seems like heater hoses, getting hot, maybe bad core??? oh and lower half of radiator seems colder than the top, new rad and therm,,

Posted by on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Geo Master
  • 14,036 Answers

Sound like radiator clogged.have coolant system flushed

Posted on Jan 01, 2013

  • Jonah Oneal Jan 01, 2013

    also have engine flushed and heater core flushed it could be clogged with rust.

×

Ad

5 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad
jimmymac725
  • 34 Answers

SOURCE: heater problems

I believe you have one of two problems either your heater core is plugged up and not allowing enough flow or the temperature blend door located under the dash is not moving.The heater core is easy to check,A quick check of the heater core is with the engine running and with the blower motor off or on low carefully chck to see if both heater hoses are equally hot if not remove them from the heater core and use a garden hose to backflush it the blend door can be more of a hassle as it can be operated by a motor or vacuum servo and even a simple cable these also have been known to break but with the blower on high change the temp control from cold to hot and see if you can hear a change in the sound of the blower and sometimes you can hear the door shut it more than likely the door is ok but you will need to check it and see.
Good Luck
Jim

Posted on Oct 07, 2008

cj2176
  • 520 Answers

SOURCE: Prizm overheats, heater core leaks, no heat

You can bypass the core or fix it that's up to you but I would change or remove the thermostat first. If it still overheats then start looking at the water pump and radiator. Hope this helps. Good luck.

Posted on Jun 09, 2009

SOURCE: i have a 1995 geo prism that the heater will not

I would believe the problem can only be in two places

  • One the control valve which operates the amount of coolant going into the system....or
  • The ducting plates inside the center consul of the heater assembly
Unfurtunatly I can't give much help in the removal of the consul as I'm not familiar with your vehicle.
  • Usually the glove locker must be removed
  • It is also possible that the instrument panel has to come out
  • The front of the consul may have screws or possibly snap fitted (if you can't see any screws) but look very carefully
  • A third possibility is that if your vehicle is fitted with electronic climate control, that unit may have a bad connection or a blown fuse.
Sorry I can't be of more help
Regards Johngee10

Posted on Oct 22, 2010

alicantecoli
  • 22246 Answers

SOURCE: heater dosnt get hot could it possibly be a stuck

heater core needs a flush

Posted on Mar 30, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

98 ford ranger no heat have changed thermostat water pump heater control valve


Maybe the heater core is plugged or you haven't bled it properly?
If the heater hose returning from the core to the water pump is NOT hot, while the hose going to the heater core from the thermostat area IS hot, then the heater core is plugged probably.
You need to remove the heater hose while cool,from the thermostat area and remove the hose from the water pump area (that's the outlet of the flow thru heater core) AND THEN take a garden hose with p-is-tol grip type sprayer,and blow water back thru the outlet hose out the inlet hose. This will blow any bad plugging material out the way it got in.
Don't apply too much pressure if it is plugged bad. The heater core isn't made to stand 50lbs. water pressure. don-ohio (:^)

Dec 31, 2016 | 1998 Ford Ranger

1 Answer

I have like a rust colored dirt coming from the radiator and radiator hoses. I've replaced the radiator, thermostat, coolant temperature sensor and water pump. I have no heat. Car registers hot but no...


Have you backflushed the heater core? Check to see if both heater hoses are getting hot and if not flush it if possible. NOTE: most modern cars run hot water through the core at all times, but direct the inlet air through the core to supply heat by use of flapper doors usually operated by vacuum actuated devices. Vacuum leak, bad check valve to vacuum reservior, or bad actuator can prevent any heat.

Jan 30, 2015 | 2001 Mitsubishi Galant

1 Answer

Inadequate interior heating


Maybe the thermostat is not opening up fully and restricting water flow. The heater core may have blockages - the heater valve is only opening partially. Gotta check out.

Aug 25, 2017 | 1992 Nissan Maxima

3 Answers

The heater is blowing cold air


Coolant system is a closed system. If you are loosing water there is definately a leak somewhere. Check all hoses after filling the system and letting it run until it's warm. Be careful when checking most systems have the water at 185-210 degrees once the vehicle is warmed up. Also check the Heater Control Valve. It allows hot water to travel to the heater core when you set the ac controls to "heat". Could be bad and leaking there. But bad hoses are the most likely culprit. Only takes a pinhole.

Jan 12, 2013 | Rover 75 Cars & Trucks

1 Answer

1995 jeep cherokee heater problems


Get jeep up to operating temp
Turn on heater to max heat
Hood feel 2 heater core hoses goint into upper passenger side of engine compartment firewall.
They should feel too hot to hold
If it's not hot, could be 6 things
1. heater control valve is bad
2. Vacuum to heater control valve is bad
3. clogged heater core.
4. Bad thermostat
5. Bad waterpump
6. Needs more coolant (check when system is cold)

Do these things:

1. Disconnect vacuum line from control valve and feel under valve to manually move valve to open position. This should let hot water flow through core. If you now have heat inside, replace the heater control valve. Or you can disconnect the plunger on the heater control that is hooked on to the silver bar on the bottom of it. With it disconnected you can manually move it to the open position. It will always remain on.

2. When system is cold, disconnect both heater hoses going to heater core. hook up a water hose to one side of heater core and flush out any gunk. When you get done, the water should run clear. If you see lots of gunk come out, that was probably the problem. Replacement is like $20-30

3. When system is hot and engine running, squeeze the upper radiator hose (using gloves) when you release it you should feel a surge of water. Proves your water pump is working. If no surge, check thermostat. If thermostat checks good, look at the weep holes at the bottom of the water pump for traces of antifreeze. If you see a trace or stream of coolant, indicates bad pump.

4. As far as testing the thermostat, watch as your engine heats up on the gauge. when it gets to a certain point you will see the temperature rise, then lower, then rise again. This means your thermostat opened properly, cooling the system temporarily, then heated it back up. Replacement is around $5

Try these and see how it goes.

Feb 01, 2012 | 1995 Jeep Cherokee

1 Answer

No heat in car, prestone level good, water pump new, heatercore seems ok. Electric control panel, no vaccum hoses. Please help!!!


heater control valve...check hoses going into heater core..both must be hot if heater control valve is good ..check flapper valve that closes off ac from heat..this is a door inside the duct work....thermostat replaced and radiator cap too.let me know just fixed my own

Jan 20, 2011 | 2002 Audi A4

2 Answers

99 jeep cherokee no heat but blower working


now there are several thing you need to check( since you know the blower and vents are working) start the jeep. let it warm up, sorry to do this to you, but turn on the heater. under the hood are two hoses going to the heater core, by the blower. after the jeep has warmed up, and heater running for about 2 minutes, check to see if either hose got warm or hot. If yes, bad heater core. if no, then the control valve that allows hot coolant to the heater core is bad. you can trace it if you follow the line to the engine, it is connected to a valve, and valve needs to be replaced( you can get it at the auto parts store). hope this helps you

Jan 15, 2011 | 1999 Jeep Grand Cherokee

1 Answer

Defrost will not come out vents


Check your coolant level first. Next check your heater control valve. With engine at operating temp and heater on high, do this:

1. Heater hose from water pump should be hot (if not, water pump may be dead or thermostat is stuck closed)
2. Heater hose from thermostat housing should be hot (if not, thermostat may be stuck closed or water pump is dead)
3. Heater hose going to heater core should be hot ( if not, heater control valve is not getting vacuum from heater control unit, or valve is broken)
4. Heater hose returning from heater core should be hot (if not, heater core is blocked, undo both hoses to core and flush with water hose until clear)

Test thermostat: with cold engine cranked, watch water temp gauge. As it gets hotter and hotter, when the thermostat opens, the temp should drop suddenly and then go back up.

Test water pump: with engine at operating temp. Squeeze top radiator hose tight, when you release it, you should feel/hear a surge of water. It is much like when you pinch a water hose closed and release it.

Test vacuum from heater control unit to heater control valve: undue vacuum line from control valve. It should have a vacuum when pressed against you skin in addition to releasing the actuating arm on the control valve.

If there is no vacuum, a quick fix will be to disconnect the plastic actuator from the silver arm on the heater valve. This will let the hot water to always flow to your heater core.

Dec 17, 2008 | Jeep Cherokee Cars & Trucks

2 Answers

1998 jeep cherokeesport


Follow these steps:

Check coolant level, then start engine until it is warm and the thermostat opens. You will tell when it does when the needle on your temp gauge goes cold when it reaches around 180-200* and then goes back up. Now turn on your heater full blast and go to the engine compartment. You will see a heater valve located on the passenger side, next to the washer reservoir. It is a black thing with 4 heater hoses connected to it. Feel the hoses. When everything is working correctly it should be like this:

Hose going to waterpump will be hot
Hose going to (I think the thermostat housing) will be hot
2 Hoses going to heater core (mounted behind firewall) will be hot

1. If only 1 heater core hose is hot, heater core is clogged--
UNCLOG: remove 2 hoses going to heater core when engine is cool, hook water hose end to one of the sides and flush out gunk from heater core. Reconnect hose and you should be good.

2. If neither hose core hose is hot, heater control valve is bad or vacuum is bad--
Test Vacuum: remove vacuum line from heater control valve, you should feel the vacuum **** on it when pressed to your cheek and the heater control valve actuator should move when you unhook the vacuum line. If you have a good vacuum, it's probable the valve available at autozone part # 5941 for around $21.

To get heat while you wait to replace part, unhook silver arm on heater control valve that is hooked to the plunger. This will give you heat all of the time, but it is controlled by the bottom hot/cold switch on your heater control unit so you won't get hot in the cab. It will just circulate heat through the core.




Oct 25, 2008 | 1998 Jeep Cherokee

Not finding what you are looking for?
1990 Geo Prizm Logo

199 people viewed this question

Ask a Question

Usually answered in minutes!

Top Geo Experts

yadayada
yadayada

Level 3 Expert

76846 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

Mike Gilbreath

Level 1 Expert

50 Answers

Are you a Geo Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...