New guy has a ecu/t-stat question

[proflow]

Hi folks, Ive been chasing a runability problem since I bought this car last month.
So far replaced parts have been: Plugs, fuel filter, oil pressure sender, & ECU.
This was on the side of the road near the auto parts store the day I bought this thing.
I then towed it home & replaced the trans mount & gutted the cat in my shop.
The only part here that actually need replacement was the trans mount.

My car only dies when the temp goes to about 205' . Below that she runs like a champ.
This is how it goes EVERY time.
I also noticed the fans didn't come on @ that temp , however its only 42' out.
I put the defrost on & they didnt come on either though.
I was going to check w/ac on but it didn't run that long at the time.

I'm thinking of slapping in a 180 t-stat or less & keep this thing in open loop, maybe hot wiring the fans also to keep this pig in open loop so it runs decent.
How cold of a t-stat can I get for this car ?
Im tired of towing & tired of paying for towing also.
No way, no how am I going to keep throwing parts @ this thing blind.
This car & I are over, There is NO love connection.
Its going to the dealer on trade ASAP.

Any thoughts ?
Anyone know what temp these things go closed loop ?

Thanks in advance---Proflow

[2000GreySSEi]

I don't know if this would work, but have you tried changing the ECT sensor (Engine Coolant Temp sensor) that could possibly cause problems like that.

[01bonneSC]

Keeping in open loop would kill your milage.

180 tstat is the lowest I would go. You can make a fan over ride switch. Ground the fans with the switch so they come on.

The fans still should come on when you go defrost or ac tho.

[J Wikoff]

Closed loop happens just shy of 200 degrees, can't remember exactly. Have you tried pulling codes? You can do so with a paper clip.

http://www.pontiacbonnevilleclub.com/fo ... =51&t=8689

After you do that, try unplugging things, one at a time, to see what changes. Start with the MAF, plug it back in, then the EGR, oxygen sensor, etc.

[00Beast]

On Series II stuff closed loop starts at 160°. Not sure if that's the same as a 92, however...

[proflow]

Thanks for the quick reply you guys !
I have pulled the codes w/clip & just got the 12 & 58.
I only checked the connection on the temp sender. It did run a little better when hot (still undrivable) after I unplugged the harness to the sensor though. I thought I found my problem. Should I pull & clean that sensor or just replace it ? Any way to check it w/a meter ? Cold/Hot maybe ?
I dont care about fuel mi., this car is short lived @ my house. Dont mean to sound rude, but yeh--its got me fed up.
I only bought it from my mom in law for temporary transportation & since day one its been a unreliabe money sucking pain in my ass. Needless to say--no love here.
So I'm thinking just yank the t-stat all together & hotwire the fans to ign.
I just dont know the easiest way to go about the fans. If they switch to ground I could set up a relay to do that if need be. I cant help to think there has to be an easier way though. Say maybe jump wire from fan relay to ign. or ?

I dont mean to sound rude here guys, & Im not the kind of person to mickey mouse anything just to sell it, but this ones going to be an exception.
Its going to be a trade in on a car lot asap.

Any more help greatly appreciated---Proflow

[willwren]

Ignore code 58. It's a known bug in the 92 PCM (all sub models). There are TWO temp senders. One feeds the gauge, the other feeds the PCM. The fans do not come on until 220°F.

http://www.pontiacbonnevilleclub.com/fo ... =48&t=1666

They should come on when the AC is on (or defrost). If they don't, something is broken. There is no 'shut down command' from the PCM that is termperature related. There is a limp mode though. You have a component that is failing when warmed up, even though you aren't overheating. I would suggest a crank sensor or ICM as the most likely culprits, but those are guesses at this point.

A fan override is very easy, but seems pointless at this time. The 180° thermostat won't do you much good without fans coming on earlier anyway. Your car isn't overheating, and we're heading into winter. Find what's crapping out and fix it, then find out why the fans aren't coming on with defrost/AC.

[myfirstbonnie]

BTW, where are you located?

[willwren]

BTW, where are you located?

Cheesehead.

[proflow]

Cheesehead ?

Im near Bonney Lake WA.

OK, well I spent the most part of the day today working blind on the Bonneville again today cleaning & lubing connections/throttle body etc...
Tomorrow afternoon my buddy is actually going to bring over a scanner.
Maybe I'll have a chance to fix this pile correctly afterall.
Oh ya, the fans finally did come on today @ one point. I thought there was an issue there, but thankfully not.
I'll keep ya all posted in what I find.

Proflow

[proflow]

OK, so I havnt had a chance to put a real scanner on this thing yet, but today I did hear if I unplugged the o2 sensor it would stay in open loop.
Sure enough, its true & it didnt cut out & die like before. This tells me there is a bad sensor thats tripping things up when she goes closed loop.
Tomorrow it goes to town to get scanned on a REAL scanner.
I'll keep ya all posted.

Proflow