1993 Chevrolet Cavalier Cooling fan problem

Do you know the location of the sensor that was replaced? Also you could have a bad new sensor or it could be the wrong sensor or the right sensor put in the wrong place.It sounds like the fan circuit is working correctly if it comes on with the ac.I have seen the wrong sensor put in the right place the right sensor put in the wrong place or just a bad brand new sensor.Also if you had a scan tool that read live engine data like coolant temp that would help.Are you using a infrared temp gun to see when the fan comes on to see when the fan turns on?Or are you using the cars temp gauge?

Hey there:

Yes the cooling sensor is the one on the drivers side front quarter panel. I found it odd when I bought the new one, it only had 4 prongs and the original stock unit has 5. Though auto zone does show the 4 prong as the right one when you look up the part. Now as far as temp, I just go by the temp gauge but I'll guarantee you when the gauge shows it getting warm, it is.

Iam just saying dash temp gauges can be wrong and i never use them to diagnose when a fan comes on.Does your connector going to the sensor have 4 or 5 wires going to it?

Hey there:

I'll take a look tonight. I did look to see if the stock (old one I kept) had 4 or 5 prongs and it only has 4. I was mistaken, autozone sells 5 prong of which I bought. I have no idea as to why the replacement has 5 and not 4. Also I noticed the old/stock unit has GM ABS V1 on it, does this relay also control the ABC System or is the numbers just a part number ?. I REALLY appreciate your help and if you guys can get me through this (the final glitch of the car) there will be yet another donation.

Thank you !

That relay is the abs relay the roman numerals refer to the model of the abs.I really wish you had a scan tool that could read live data of the actual coolant temp the computer is reading.

What are the wire colors to the sensor that was replaced?

I just looked up the coolant temp sensor for your 1993 chevy caviler on the auto zone website and it shows a 3 pin sensor for your car.What are the wire colors and the numbers of wires to the sensor you replaced?

Good morning:

The coolant temp sensor has been replaced, it has a three wire sensor as you said. I put the old coolant fan relay back on yesterday and the fan still does not come on (probably why I had bought a new one and replaced). ALL the parts were replaced, the temp sensor (which the mechanic had told me the reason the fan originally wouldn't come on was the reason), has been replaced twice, once by them and again by me. In will check but I think the wires going into the connector only has 2 wires. The fan worked right up until I took the car into Discount tire and had the tires, struts, brakes, etc replaced AND the mechanic there said they could replace the radiator and fuel injectors (2 were leaking and radiator was shot from sitting so long) also. I was VERY skeptical to let a tire shop do this but went ahead. That's when the fan wouldn't come on (I sat there 8 hours not knowing what the hell). Then I was told "we got the fan to come on by changing the TEMP SENSOR and yes it did, 40 degrees hotter then it used to come on, going by the temp gauge. And again, now it won't come on at all. Last gig on this beautiful car and it's driving me nuts !!!!!!!!!!!!!!!!!!!!! In the day I've built many a "hot rod" motor, I have an off road race team with a Trophy truck and numerous motorcycles we race, I ain't no dummy. BUT............when it comes to the newer stuff and me getting a bit lazy, I take my car in for any repairs, just don't have the iggy you guys do. I just went out and checked, 3 wires to the sensor, green, yellow and black. The go into a massive wire loom/harness and the 2 wires to the fan, bigger gauge wire, purple and black. You guys are good, I'll throw another $100 smackers in a donation if we get through this.

Let me know how to proceed and muchos,

Ron

If you turn on the ac and the radiator fan comes on that tells me the relay fan and wires are all good.Try this start the car up and unplug the sensor does the fan come on?

Do you know how to flash the codes out of the check engine light thru the obd1 connector?If so with the key in the run position jump the obd1 connector to flash the codes is the radiator fan on?Also do you have a infared temp gun to measure surface temperature?

Yes sir, I've done that and it comes on, just like I THINK it's supposed to do ?

So the fan driver in the computer is good and the fan and fan circuit is good.Do you have a infared temp gun to measure surface temperature?

Yes I have a OBD1 tester and No, Infrared tester. There are NO CODES coming up, nothing. Nest idea ?

Heres what i always do with a fan issue when i know the fan circuit and computer fan driver is good i hook up the scan tool and compare the actual coolant temp verus what the computer sees.But you dont have a scan tool so what i would do since the sensor is new and i dont trust your temp gauge on the dash they go bad and usually read higher than they should the ones i have come across.I would get a infared temp gun they have came down alot over the years i bought mine when they first came out.150 in 1995 and i still have that same gun works great still.There like 20-50 you could probably get one cheap at harbor freight.I would let it run while measuring the coolant temp at the thermostat housing the fan should turn on at about 221-223 sometimes a little higher depends on the car even the same make and model.You can use that temp gun for a lot of different things there nice to have.

Can your obd1 tester read live engine data like coolant temp?

Good morning:
I sure hope this doesn't go to your cell phone and if it does, wakes you. Getting ready to head to a race at Glen Helen thus up early on a Sunday and your reply. No I don't think the scan meter work as you ask, it just tell you what ever code may have come up. I'll see if I can locate a infrared tester and give that a try. AGAIN, keep the info coming and thank you ! We will conquer this matter ! If the temp gun shows what the dash gauge shows and the fan still is not coming on, then what ? Just asking so you will be prepared.

Ron

I'm tempted to take the car to the gentleman that builds the engines for the race truck but he's in Barstow and he's already "donated" so much time in the truck that I really don't feel comfortable. Thus the reason I've been paying mechanic's (mobile ones also) plus by paying some of these peeps, I'm helping them out also. I've never been one to ask for anything free and always the one to give more than expected. But I will see if I can locate a infrared temp gun and try to get this done with your help.

Thanks again,

Ron

You live in California? Where abouts?

If the fan still doesn't come on i want to see what the computer is reading.

Good morning:

I live in Yucca Valley, just north of Palm Springs. The scanner I have is the type that only reads and gives results to codes, it doesn't have the ability to
actually read anything and the "check engine" light doesn't come on thus no codes to read.

I just can't figure why the temp gauge would just "all of a sudden" start reading incorrectly, just doesn't make sense. But you are the brains behind this dilemma, not me.

Lets see with the infared temp gun what temp the fan turns on at makes it hard to not be able to see temp the computer is seeing
Also what is the part number of the sensor you just installed the number on the part itself that you just put in?

Good morning:

A mechanic buddy of mine will let me borrow his infrared temp tester and I'll test it when I get home. I'll see if I kept the box the sending unit came in so I can supply you the number.

Thanks, again !

I was hoping for the part number on the part itself to rule out part was miss boxed etc i have seen that before.

I'll see if I can see the number and if so, I'll let ya know.

Ok

Well Bubba......................you were right once again ! With the infrared tester the fan DOES COME ON at 232 degrees and shuts off at right at 200 degrees, and I checked it three (3) times ! The gauge as you had said is WRONG, what a relief. So I owe you another hundy as promised. NOW, how do I go into a donation mode to kick you down my promise since we started out with the first page where a donation is possible to insert ?

Man, I'm finally done ! THANK YOU, THANK YOU !

Ron

Do you mean the fan comes on at 223 not 232?Also i will get you the info on Making a donation.

Hey bubba:

Yes I am the king of transposes !!!!!!!! I meant on at 232 and off at about 200-202 degrees. Also since I've got your ear. I had changed the EGR valve as part of my trial and tribulations on the car and when I took it for smog, the mechanic stated the one activates (opens) with just vacuum and thus doesn't stay open. He mumbled something to the effect the original OEM works off of vacuum AND pressure and I may need to get a OEM, does that sound correct ?

It makes mechanical sense thinking some exhaust pressure might be needed, just surprised again if I was sold the wrong part.

Thanks buddy !

Ron

I just looked at your egr valve looks kinda like a older saturn single cam engine egr valve.I dont see why it would have to be a factory egr valve i would just get a aftermarket market one if it were my car.Looks like the egr valve gasket has screen on it.Which is rather strange so is the diaphragm in the egr valve not holding vacuum anymore is that why there telling you to replace it?

Yes sir ! It is brand new (not OEM) and they stated it would not pass smog due to it not holding vacuum. Who knows but I have a spell before I have to have it re-smog so I'll just sit back and wait. Now, my new gasket did not have a screen on it nor did the old one when I replaced it so something there is different and no, it's never been changed until I did it and I'm the original owner.

Thanks and have a GREAT day !

Ron

By the way if I test the temp at the thermostat after just coming out of the radiator the temp the fan comes on is more like your 220 degrees, I was testing the block temp literally where the thermostat housing bolts to the engine, maybe the reason at that location, the temp is a bit warmer ?

But the temp ON the thermostat housing the fan was coming on at about 220 and off at the same of about 200. Makes sense ?

Ron

You have to be careful where you measure the temp sometimes you can get a false reading measuring the exhaust etc rather then the coolant temp.The fan turning off at about 200 sounds about right.It says the fan turns on at 221 so i say around 221-223 the fan would turn on from what i have seen with other cars.I saw the screen on the egr gasket on the auto zone phone parts app.I look at another source to see what they have.the egr valve should hold vacuum or it wont open.You can use one of those hand vacuum pumps with the gauge to test it.

Yes sir, so the temp on the thermostat housing (there housing where the hose connects, shows 220-223 degrees when the fan comes on and right at 200 degrees the fan shuts off, I think all is good.

Ron

That sounds perfect for the fan turning on and off.

Did you get the message from mike at 2carpros telling you how to donate?

No I haven't but I've been out of town and have got to go back out and thus the reception in the hotels is a bit unreliable to say the least and I get a lot of good email messages shoved into my spam file (which self cleans every 12 hours) when there isn't good reception. Have him give it a try again !

Thanks,

Ron

I emailed mike to resend the info on donating.

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Thanks again,
Mike