xkazik

iTrader: (14)

Hello everyone ! been a while since i posted on the org , i Have bought a maxima again , my 3rd one and i have a problem with it , The car doesnt over heat normally ,only when the A/C is on , once i turn the A/C off the car goes to its normal temperature within couple of minutes of driving , i have coolant and the fans do kick in , did anyone else have this problem before ? please help thx in advance

Quickywd01

iTrader: (16)

Your condensor might be dirty. Condensor is the ac radiator in front of the engine coolant radiatior. Look at it, clean it, use a hose, etc. If not check the rad cap, thermostat, coolant flush, etc.

xkazik

iTrader: (14)

ok thx . Ill try to cleaning the condensor with a compressed air tomorrow, from what previous owner told me the car did have a flush and thermostat was replaced , any way a going bad ac compressor can cause this ? just trying to look at this problem from every direction. A?C blows really cold as well

Quickywd01

iTrader: (16)

Look at the condesor/rad with a flashlight, if it's dirty you will see. I doubt it's the compressor.

xkazik

iTrader: (14)

it does look pretty dusty , the car has 175,000 miles on it , the radiator looks original tho , thank you for your input, can a dirty condenser really cause this kind of problems ? seems weird too me

JvG

I replaced my radiator recently. The top tank was starting to seperate. It appeared to be original equipment, so it might have been 18 years old. I noticed that the back of the radiator appeared clean. The front side of the A/C condensor appeared clean as well. When I removed the radiator, I noticed a lot of stuff was blocking the air flow. I blew out the condensor front to back, with compressed air.

It is possible that you may also have blockage between the radiator and the condensor.

You could have enough water flow, but not the required air flow

You have enough airflow to handle ordinary driving, especially at normal speeds. Just not enough air flow to handle normal engine needs and the air conditioning at the same time.

Remove the radiator and check for crud there........

good luck.....

ChrisMan287

iTrader: (34)

I have a feeling it's a fan issue. Do both of yours work?

JvG

You mention that your A/C does blow cold. That means that the A/C and compressor both work. The thermostat was replaced by the previous owner. The previous owner also had a flush done. He must have had the same problem that you do.

ChrisMan287, Quickywd01 and I, are pointing to the same thing, AIRFLOW. You mention that your fans, I believe you mean BOTH OF THEM do turn normally.. ..

I believe that the most likely problem is crap between the condenser and the radiator, or an internallly blocked radiator. First, remove radiator. Clean out any crud you see. Then blow out both the condenser and the radiator fins with compressed air. This might fix the problem. If not, and the fans both turn, I would have the radiator internally flow tested at a radiator shop.

There is a group buy on the Koyo radiator. It worked for me....

If the old plastic one worked for all this time, a new one should outlast the car.

xkazik

iTrader: (14)

Ok thx guys, I will see tomorrow and report back, but from what I noticed, both fans do turn on.

xkazik

iTrader: (14)

ok so i got chance to work on the car today . I blew both the condensor and radiator out with compressed air . The problem still exists. Got a chance to drive the car aound and play around with it . so this is what i noticed
1 Both of the fans work
2 coolant looks green and fresh
3 there wasnt that much dirt in the radiator and condensor
4 the car only overheats with the ac on goes to about 3/4 once i turn the ac off it goes down to mid way and stays there , if i turn it on again it goes back up

what do you guys think i should do next ? the last owner is working with me to solve the problem and i believe he is trust worth in what he says

bprice92

iTrader: (2)

Hows the condition of coolant temperature sensor? When mine was going out it would cause the temp needle to fluctuate.

doesn't explain the ac situation but worth a shot to inspect the sensor/ wiring.

JvG

You probably STILL have crap caught between the condensor and radiator. I also blew air through the condensor towards the radiator, and from the radiator through the condensor. I imagine you tried that.

When I replaced the radiator, (due to a leak at the top tank) I STILL found a lot of crap between the radiator and the condensor. I feel that your problem is related to the layer of crap between the two.

When you blow air through the condensor and the radiator, the stuff gets trapped between them. That is what caused the crap layer. You might THINK you eliminated the problem, but you did not.

To eliminate the possiblity of the crap layer causing your problem, please remove the radiator. then you can get rid of the crap layer, and also be able to blow air through the radiator and the condensor. What I am suggesting does not cost money, just time.

xkazik

iTrader: (14)

I took the top radiator mounts off and i dont see any crap in there, it looks really clean , I think i will replace the radiator since its still the original one , is it possible that the radiator is failing inside and not leaking ? It really looks like theres nothing in between the radiator and condensor , im just worried that something else might be causing the problem

JvG

Thanks for checking for the crud. If it is clean in there, the next step is to take the radiator to a radiator shop and having it "flow tested". What they do is measure the water pressure on the inlet side verses the outlet side (or something like that. They are checking to see how much of the radiator is blocked from inside.

In the days of cast-iron blocks, rust particles would go into the radiator and get trapped there. The cure used to be to take the copper tanks off and shove thin rods through the radiator passeges (known as rodding the radiator. With plastic tanks, I hear that replacing the radiator is all that can be done.

When you take the radiator out, check for the crud I am talking about.

Just curious, has anyone else had a radiator on our Maximas get blocked on the inside?

xkazik

iTrader: (14)

How can i tell if the radiator cap is good ? is it possible that that is the problem? I am replacing the radiator this weekend or maybe even today if i find time , i would like to get to the bottom of this problem , so i dont have to stare at temp gauge all the time being all paranoid

JvG

A bad radiator cap would not hold pressure, and could be your problem. When your engine gets too hot, look for lots of coolant in the expansion tank. Then when the engine cools down, coolant should go back into the engine. If the radiator cap lets go at too low a pressure, your engine could over heat.

A radiator cap is only 10 bucks or so. You might consider buying one, just to eliminate the possiblity of a bad cap. It might solve your problem. Otherwise, you know that you have a good cap to go with a new radiator.

xkazik

iTrader: (14)

i also noticed the ac makes noise , when i turn the ac off the noise goes away , can this cause over heat in any way ?

DennisMik

iTrader: (2)

The a/c won't make any abnormal amount of heat just because there is a noise. A little bit of noise is normal but without hearing the noise I won't even attempt to guess what it might be.

The overheating could be caused by a non-Nissan thermostat. There are many, many threads here about that.

1992maximase30

Now do the fans turn on high speed. That could be your problem.they're running on low and when the engine needs that added cooling while the a/c on the fans turn on high speed. also are you sure its overheating like the coolant start to boil? Cause be a faulty temp sensor for the gauge

Reality sucks

iTrader: (3)

sounds like a ground problem guys, I've seen this, the ac electrical load creates amp draw, resistance, temp gauge works on ground.. im a master tech, so check them.. seems as if all other items mentioned checked out ok .and yes every maxima I've ever worked on (allott) has had that damned ac noise. Perfectly normal,. good luck

Jaehblue3

iTrader: (1)

I had this happen to me before in my max. It ended up being the thermostat. Replaced it and haven't had he problem since

xkazik

iTrader: (14)

thx for all the info guys , i will continue to diagnose this problem right after i pass inspection , first i have to change the oxygen sensor because i got a p0171 code , hopefully after that my monitors will be ready as well, that's the reason why it failed in first place , seems like the battery was disconnected before i bought the car to hide the check engine light ....
should i run a extra wire from the ac to the frame to make sure its grounded well ?

1992maximase30

That abnormal normal noise (probably the compressor being extra loud) when it circulates the refrigerant and its not getting cooled properly i notice that too. Seen it quite a few times and when the fans finally come on like they should the compressor gets quiet. I believe either the fans or not cycling between hi and lo like they should or either its the thermostat.

DennisMik

iTrader: (2)

The radiator cooling fans run at low speed when you turn the a/c on. When the coolant temperature reaches 200 degrees Fahrenheit, the fans run at high speed. The 2 fans always run as a pair, never just one.

This is all based on the engine coolant temperature sensor (ECTS) being accurate.

Elizabeth Melgoza

I recently had the alternator changed along with the belt but when the ac is on the belt screeches the car only has 80,000 miles but I’m pretty sure thermostat has never been changed but car just started overheating today so I’m wondering if the belt has anything to do with it overheating when ac is on

JvG

Other types of cars have belts which turn the alternator and water pump. A loose belt would screech and could result in overheating becsuse the water pump isn't turning.

The water pump in our cars engine is not driven by the belts.

The pump is driven by the timing chain inside the engine. It is turning as it should.

So the loose belt is a separate issue. You could tighten the bolt on the belt tensioner.

You might have a leak somewhere. Remove the radiator cap when the engine is cold. Add coolant if needed. Monitor the coolant level over days.

Check the oil level. Also make sure the oil does not look like a milkshake. Occasionally and rarely the pump leaks into the oil. .

Check the fans. Both should be on when the air conditioner is on.

Is the problem less when the car is moving, and worse if it is stuck in traffic.

Elizabeth Melgoza

I first thought it was thermostat I changed it still had overheating . Then changed the compressor still overheated so what finally fixed it was changing radiator put a new one in and no longer overheats!!!