KED85

Hey All
Other day my car died due to radiator plastic side pod cracking.
Luckily it died right near a water foutain (really!) and I had a plastic jug to refill radiator until the problem was located.
That doesn't mean I was able to make it home ok.
Yes, eventually that crack "stilled my progress", again.
Made it home.
Next day went to yard and scored a great Firebird aluminum radiator, installed it, more problems arise.
First check engine light appears, fan comes on instantly.
Eventually the starting & stopping of the car (testing for leaks), "removed the check engine light". BUT the fan did NOT come on.
SO car overheats in driveway, no biggie I shut down, consulted friends and have replaced the thermostat & upper hose.
Feeling good about progress, I restart car with all new parts, high fluid level in radiator & it seems to work right.
The fan came on by self, I think GREAT!
Had to take a call.
Shut off car.
Go back outside, and restart car, awaiting the start of twirling fan blades, NO FAN AGAIN & NO CHECK ENGINE LIGHT saying I have a problem.
I remove the cap (to let engine burp the "air pocket" as suggested), all I get is fresh fluid down the driveway. And need refill radiator, again!
I go back to other plan and just hit the AC switch as the engine is on & cap is off (for observation of water flow, level, etc).
Then the fan does come on (due to AC usage) & "all seems fine".
YET I know it's not.
I'm playing chicken.
I'm gonna take it to a genius and let him figure out what ails my ride.
But in mean time, I'll let anyone else have a say as a cause!
PS I'm too chicken to even now shut of AC until I'm at this mechainc, but I'm happy to hear your ideas!
With AC activated fan going and full radiator, NO overheating at all (so far)!

Oh and ask me about radiators & the F Body, Camaro/Firebird V6, Carb'd V6, Carb'd V8 & MPFI & 1990-1992 3.1s, TBI V8 & TPI V8s!
I never knew our F Bodys had so many choices, The 1985-1989 Firebird V6 is limited to ONLY ONE RADIATOR OPTION!
Which is the Aluminum radiator and inlet on driver side. Yet this radiator is ONLY 3 short inches narrower than a Camaro TPI V8 radiator (aluminum).

Well let's hear your thoughts!

Yes I have already replaced my fan sensor back in 2000 AND I also replaced my ECM, too.
All worked FINE before the stall on road side other day. No wire hack jobs in the system.
NO I have NOT cleared any codes yet. I am going to let this genius "do that" if needed and learn from his diagnostic skills about this problem.
But I'm open to your responses.
Thanks

85berlinetta2.8

what code was it giving?

i bet it is whatever checks the coolent temperature. coolent temp sensor.

and whatever turns the fans on. fan relay?


or
coil
coil
coil

just kidding

KED85

I'll tell ya
I'M GONNA STAY LAZY
and just tally up the responses.
No I haven't pulled codes nor plan to.
I'll leave that surprise.
Besides I want car checked over after this incident anyway. This guy also has a tool to check for head gaskets. I'll work with that response of his, to see what is this tool.
I had recent installed tranny. Like 5 months old.
I'm gonna swap out the fluid for fresh.
Need to change oil, too.
You say Temp sensor. My fan sensor again is very recent. But was also told to ground it to test if that sensor is bad, too.
Keep tossing them ideas out.
Thanks!
PS engine still pulls strong!

85berlinetta2.8

....why wont you pull the codes?

KED85

Really too busy to worry what they may say.
When I get it to the mechanic he'll tell me.
Even IF I find out the cause of sensor, I'll have them replace it, if price reasonable.
The fact I got all this stuff swapped, changed thermostat without removing upper intake, no leaks, I feel pretty good.
The fan on & off is just a by product but interested in hearing any ones solution to offer.

Project: 85 2.8 bird

plastic rad fails due to temps heating up & expanding plastic. Check your tranny fluid for coolant.

also replace that inexpensive fan switch on the back of pass head, and temp. Sounds like it's doing whatever it wants to.

put car on ramps & then open rad cap to help air find teh highest point in circuit & burp out there.

KED85

I'll be able to check how well car "burped" in AM when I open the tank up. I think fluid level will be good. Yes, told low coolant level fluid will cause the no fan on condition. But due to test driving today, again in AM will see those results.
Yes adding more tranny fluid THANK YOU!
I already know I need replace coolant sensor up front. Back one, oh I pray no replace! I hate that one!!

RTFC

I know you said you replaced it 4-5 years ago but I would insist its the fan relay switch.

The sensors on these car a a pain in the rear and even new parts on mine fail regularly. I gaurantee thats why the radiator cracked- old age and overheating ill crack them plastic rads every time when they are more than about 8 years old. That fan not moduating on properly will do that in a heartbeat.

KED85

Two for fan relays!
Yech!
I'll keep allposted.
Not going to the shop today due to I need start another project and arrange a car for rent.....
Atleast I can keep fan on with AC so this band aid works for a day or three.
Remove relay from below, ok, good clue....

molopaa

iTrader: (1)

Did you purge your rad of air? Meaning did you run the engine for 10 minutes with the rad cap off?

If not, then I say air pocket(s) in rad and the temp switch is not getting coolant all the time and therefore turning the fans on/off irregularly

KED85

I believe I've air pocket'd the car to death!
I'll check this AM for fluid level in rad, to see.
I drove decent distance for testing, yesterday and checked several times for rad resivour level.
Why can't someone say oh replace the radiator cap with new one & you're good!
More Sensor answers/suggestions.

KED85

This AM looked at radiator level. It was full! Good sign!
Checked tranny fluid level, smelled ok & was also full, too!
So good signs so far.
I kept fan on by using the AC system, a good thing
and no overheating due to that AC-fan usage.
BUT
the car...
Bucked IF I gave it part throttle
No bucking if light on the gas pedal
No bucking IF I floored it
So I get new sensors
-Oxy Sensor (due to I need it to pass smog anyway)
-Air Intake Sensor (due to why not just incase)
-Coolant sensor on intake manifold (Due to I know I need that cause I saw a code for that)
-The dreaded Fan sensor switch.
AND A GOOD ECM Just in case!
Made it over a distance of 25 miles (with NO overheating!!) to the Genius.
I bought him old parts (thermosat that I replaced and the old hose & old radiator)
We'll see!
Any other ideas for sensors to replace?
Any other ideas of problems?
Thanks all for chipping in to solve this one for me!

Project: 85 2.8 bird

I'd still flush teh radiator fluid just in case. Clutch paks aren't all that cheap to replace.

KED85

I asked the genisus to check my tranny fluid for their opinion if it's burnt fluid in need of changing.
I also checked fluid this AM and saw no bubbles or any danger signs.
But again I already put that plan into action at the genisus bar.

Project: 85 2.8 bird

I keep saying this because when I had a 92 Bonnie, the owner had the plastic radiator crack & fluid exchange. He could tell from teh wonderful froth in the coolant. He bypassed the rad w/a remote tranny cooler, but never got the tranny fluid exchanged. When I got it, the tcc lovingly rusted up & clutch paks were eaten away.

That repair job wasn't cheap

KED85

The Genisus called
SAID IT WAS A BLOODY AIR POCKET!
Fan comes on at 220* & shuts off at 200*!
Just like it should!
Well I am peaked to say the least!
THANKS TO ALL FOR THE SUGGESTIONS!!!!!!
I mean think of this
How many mechanics would say to you your car had no problems except hot air pocket!!!!!
I am so pleased
I get to now drive it in Southern California bumper to bumper traffic! as another test drive!

KED85

Brought it back from mechanic & we saw fan cycling on & off correctly.
No code flashed in the dash.
I drove 25 miles and the car was a dream again! Powerful, smooth running accelerating no bucking.
Bring it to my tranny guy (he was on way home) due to the bottom tranny line is leaking outta radiator, drip drip.
I tired tightening it. It was tight.
Still leaks at tranny fitting, later on we'll try fixing it or swapping in a new fitting.
AND we checked tranny fluid 4 times for smell & wrong fluid. I'm good!
BUT
On way back home from tranny shop, the car bucking reappeared. When we got home the car overheated.

I still have my sensors with me and Saturday AM gonna have them swap them out for mine. I'll be driving with the AC on for rest of week.
But the car bucking problem is weird.
Good thing is I also have a spare ECM but doubt my problem is that deep.

How does one access the fan sensor while engine in car? From down below?
Thanks all!

Project: 85 2.8 bird

dude, you lost me there.

on everything else!!!!!!!!!

KED85

Last time I accessed the fan sensor switch the engine was outta car SO IT WAS EASY!
With engine in car, any suggestions?
DO I go reach up from below to loosen it, remove it, replace it, tighten, click on connection?
I'm now just driving with the AC on, so is the radiator fan, constantly.
Car still bucks, then it doesn't buck (smooth driving). In the Factory Pontiac Helms book, it states that this coolant sensor does control Fan activation also Throttle sensor postioning and timing. All things that does affect my smooth driving.
I hope!
I'm doing this sensor switch swap! Sat. AM. Too hot & no time.
I'm off shortly to fix the leak in tranny line at bottom of radiator. At tranny shop. Tranny shop owner gonna help me. Nice!

KED85

MY CAR IS FIXED
COOLANT TEMPRATURE SENSOR DID THE JOB ON ME!
LOUSY STUPID $16 SENSOR!
NO MORE BUCKING
FAN GOES ON & OFF
DAMN LOUSY $16 SENSOR!
BUT REPLAVING THAT LOUSY COOLANT TEMP SENSOR SAVED ME FROM REPLACING THE FAN SENSOR AT BACK CYLINDER HEAD.
IF YA GOT SOME DRIVABILITY PROBLEMS IT CERTAINLY CAN BE TRACED TO THE COOLANT TEMPRATURE SENSOR!
MY PROBLEM IS NOW SOLVED.

BitchinRS

Is that sensor the one in the manifold next to the t-stat housing? I have been having the same intermitent stumbling problem. Goes easy into the gas and no problem. Mash the fun pedal and it bogs then picks up. Happens both cold and warm.

KED85

Yea that's it!
I tackled mine using a 3/4 deep socket not for spark plugs, placed it down there using a 8" extension, twisted out easy.
HARDEST PART WAS
Making DAMN SURE I did NOT cross thread upon reinstallation.
I used LOTS of teflon sealant in a TUBE on threads
I spray cleaned the area BEFORE I remove the item, so nothing got inside the water passage.
Since previous owner already had this job done once before I need not change the wire clip connection assembly.
Removed positive cable for like 15 plus minutes.
Prayed.
I was ready to dump the car if this not work.
Workes great NOW.
Got fan to cooperate properly and car not overheat and no bucking at part throttle.
NOW IF
Morning AM drive is same smooth driving experience, I solved a very big problem with my ride.
AND IT pushes back that minivan a bit further!
Also install a new thermostat same time!
I was handed a 180* and was told that's ok, I really wanted a 195*, tho.
My fan comes on at 217* at shuts off at 190-200* range.
It was like 90* today. I drove over the killer Sepulveda Pass hill and no need to pull over! I sure know car works right using the AC, G0d loves R-12!