Thermostat & oil pressure switch location '01 Impala +
sassygramma
03-09-2009, 03:37 PM
Been searching these threads with no luck, or just tired eyes. Can anyone give me an idea of where to locate thermostat & oil pressure switch circuit on '01 Impala (3400 v6) ?
Also, is there only one, or is there 2 thermostats? Mechanic gave estimates on some things to fix, and stated there are 2. Bit confusing.
These are the codes given for estimates: check engine light needs thermostat - code P0128 & oil pressure switch circuit - code P1189. Estimates came back at total of $625 for both of these, so if we can do it ourselves, any info on either of these would be appreciated.
Also, is there only one, or is there 2 thermostats? Mechanic gave estimates on some things to fix, and stated there are 2. Bit confusing.
These are the codes given for estimates: check engine light needs thermostat - code P0128 & oil pressure switch circuit - code P1189. Estimates came back at total of $625 for both of these, so if we can do it ourselves, any info on either of these would be appreciated.
HeMi101
03-09-2009, 08:25 PM
Oil pressure switch is down by the Oil filter on the 3800, I'm Pretty sure its in the same general area on the 3400. Only one Thermostat, and AFAIK Its right below the Throttle body. Real SOB to do your self on the 3400, alot of guys let a mech. do it.
la1
03-09-2009, 11:20 PM
These are the codes given for estimates: check engine light needs thermostat
1. what does yor eng temp guage read?
2. do you have the right quantity and mix of coolant?
3. when was the last time the coolant was changed?
4. is there coolant in the resevoir and what does it look like?
5. do you jave any coolant leaks?
the thermostat like said above is under the throttle body, you have to take off the intake and the exhaust crossover off ( which the flanges may be rusted
the oil pressure sending unit is like said above is right near the oil filter. the only other like unit is the knock sensor...that just screwas into a blanl whole...no oil will come out.
1. what does yor eng temp guage read?
2. do you have the right quantity and mix of coolant?
3. when was the last time the coolant was changed?
4. is there coolant in the resevoir and what does it look like?
5. do you jave any coolant leaks?
the thermostat like said above is under the throttle body, you have to take off the intake and the exhaust crossover off ( which the flanges may be rusted
the oil pressure sending unit is like said above is right near the oil filter. the only other like unit is the knock sensor...that just screwas into a blanl whole...no oil will come out.
sassygramma
03-10-2009, 07:53 AM
[quote=la1;5931554]1. what does yor eng temp guage read?
2. do you have the right quantity and mix of coolant?
3. when was the last time the coolant was changed?
4. is there coolant in the resevoir and what does it look like?
5. do you jave any coolant leaks?
1. Temp gauge is down, as if engine is cold, (I dont drive it, so just going by what husband states) even when driven for a few miles. After car was shut off, the fan (apparently it is a cooling fan) would stay running.
2,3,4. Just took it in for radiator flush, (which the coolant was nasty looking but he had added some green antifreeze to the dex-cool), so one can maybe assume the nasty color was due to the mixing. And so far since the flush, it has taken care of fan running, but temp gauge is still not giving any kind of reading.
5. Have not noticed any leaks, nothing on garage floor or anything. Husband added some antifreeze cause the reservoir looked a little low. But it wasn't a whole lot that he added.
The tech guy did some checking about the temp gauge though, said codes show we need thermostat, and then also this oil pressure switch. And the car itself does not seem to be showing any indication of overheating.
Like I said previously, if this is something we can do ourselves, the parts do not seem to cost all that much, so the main charges quoted to us would be labor. But, if its gonna be a PITA, then we might not have a choice but to pay it.
2. do you have the right quantity and mix of coolant?
3. when was the last time the coolant was changed?
4. is there coolant in the resevoir and what does it look like?
5. do you jave any coolant leaks?
1. Temp gauge is down, as if engine is cold, (I dont drive it, so just going by what husband states) even when driven for a few miles. After car was shut off, the fan (apparently it is a cooling fan) would stay running.
2,3,4. Just took it in for radiator flush, (which the coolant was nasty looking but he had added some green antifreeze to the dex-cool), so one can maybe assume the nasty color was due to the mixing. And so far since the flush, it has taken care of fan running, but temp gauge is still not giving any kind of reading.
5. Have not noticed any leaks, nothing on garage floor or anything. Husband added some antifreeze cause the reservoir looked a little low. But it wasn't a whole lot that he added.
The tech guy did some checking about the temp gauge though, said codes show we need thermostat, and then also this oil pressure switch. And the car itself does not seem to be showing any indication of overheating.
Like I said previously, if this is something we can do ourselves, the parts do not seem to cost all that much, so the main charges quoted to us would be labor. But, if its gonna be a PITA, then we might not have a choice but to pay it.
Airjer_
03-10-2009, 08:41 AM
P0128 = coolant temp below closed loop threshold. Which means that the coolant temp isn't getting up to normal operating temp. The standard diagnostic procedure is to start up the car and let it run while monitoring the coolant temp. If it never gets to 195 degrees than its fair to assume that the t-stat is stuck open. Also if the upper hose warms up shortly after starting the vehicle than the same can be concluded. These are really common! They can be replaced without pulling the upper intake and crossover pipe, but they are a lot easier to replace with the lower intake on the bench.
la1
03-10-2009, 08:00 PM
If it never gets to 195 degrees than its fair to assume that the t-stat is stuck open Interesting, so even on a hot day it would not get above 195?
Airjer_
03-10-2009, 11:29 PM
These codes are more common in the winter because of the very cold ambient air temps we have in the midwest. So they are more commonly diagnosed in the winter.
Iflylow
03-12-2009, 11:16 PM
$625 sounds kind of high for those two. Granted the thermostat is a little hard to get to, but once the crossover is out of the way it's not bad. The oil pressure switch is down above the oil filter, two wires run to it, one brown and I think the other is white. It shouldn't be hard to remove and replace, but you will lose some oil doing it.
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