Oil temp is too low.
Thread Starter
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Oil temp is too low.
The car is a 99 automatic convertible with 37,000 miles. The only mods I am aware of are shorty headers and a Breathless Vortex ram air kit. It starts and runs fine with no codes. The car is driven mostly on weekends when the weather is dry.
The water temp. runs in the 160’s no matter what the outside temperature is, I’ve driven it when it’s 90 deg. and 20 deg. Upon startup it goes up to 160 and stays there. Last year I let it sit at idle and the temp. went steadily up to the 240 range and both fans came on at the proper temperature before I shut it off. This leads me to believe that the water temperature gauge is functioning properly.
My concern is the oil temp stays at 175 to 180 unless I really get on it. I assume it has a 160 deg. thermostat based on how it behaves. I’m guessing that the previous owner had the timing advanced when the mods and the 160 were installed. Is there any way for me to determine what the timing is without getting a tune? I would like to install a higher degree thermostat in order to get the oil to 200 but I’m afraid it might result in engine knock if the timing is too far advanced for the higher temperatures. Thanks in advance for your help.
The water temp. runs in the 160’s no matter what the outside temperature is, I’ve driven it when it’s 90 deg. and 20 deg. Upon startup it goes up to 160 and stays there. Last year I let it sit at idle and the temp. went steadily up to the 240 range and both fans came on at the proper temperature before I shut it off. This leads me to believe that the water temperature gauge is functioning properly.
My concern is the oil temp stays at 175 to 180 unless I really get on it. I assume it has a 160 deg. thermostat based on how it behaves. I’m guessing that the previous owner had the timing advanced when the mods and the 160 were installed. Is there any way for me to determine what the timing is without getting a tune? I would like to install a higher degree thermostat in order to get the oil to 200 but I’m afraid it might result in engine knock if the timing is too far advanced for the higher temperatures. Thanks in advance for your help.
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
Well you don't want the oil temp. that low, so unless there is somthing else causing the problem, you're going to need to change stats anyway. It's odd that the water temp is so low with the 160. I'm running one and like many others on the forum, mine runs around 182-187 most of the time (except stop and go traffic)
It sounds like you're only guessing that the timing was advanced, so IMO you should just go ahead and put at least a 180 stat in and listen for any pinging. If there is, go get a PROPER tune (that doesn't put so much emphasis on timing) There's not THAT much perfrmance increase in these engines running super high timing anyway
You need to get your oil temps in the low 200s to prevent wear to the engine
It sounds like you're only guessing that the timing was advanced, so IMO you should just go ahead and put at least a 180 stat in and listen for any pinging. If there is, go get a PROPER tune (that doesn't put so much emphasis on timing) There's not THAT much perfrmance increase in these engines running super high timing anyway
You need to get your oil temps in the low 200s to prevent wear to the engine
Safety Car
Joined: Aug 2000
Posts: 4,933
Likes: 30
From: San Rafael CA
You don't want either the water or the oil that cold .... geez for the water at the head (where it is measured) to be at 160 ... it must be coming out of the radiator at like 140 or lower ..... I'd almost suspect that the thermostat in there has been "altered" to even lower than 160, or is somehow "jammed" open .....
Regardless, you need to replace that thermostat as soon as possible. Since your fans are apparently set for stock, I'd almost suspect that the car has not been tuned, as most tuners alter the fan on/off temps when they put in the lower thermostat. Plus, shorties and an intake system don't really alter enough to usually need to be "tuned".
Put a stock thermostat in and see what that does. If the timing has been altered the KR sensors will (should) give the PCM enough warning that the PCM can retard ignition sufficiently to eliminate the problem.
Replace the thermo and let us know how it runs after that ....
Thread Starter
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Thanks for the advice guys. I just got off the phone with Gene Cully after ordering a stock 195 thermostat. It's funny how some of the catalog houses only sell the thermostat housing along with the thermostat. Gene said he will send me just the thermostat. I post back when I get it installed. Thanks again.
Thread Starter
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Today I installed the new 186 degree thermostat and took the car out for a 20 mile run The outside temperature was 49 degrees. Water temp went to 192 very quickly and stayed there. Oil temp was much slower to rise but it got to 199-202 and stayed there. Considering the outside temperature, I’m satisfied with these temps. Seem pretty normal to me. No knocking or hesitation.
One disappointment was I couldn’t use the Delco thermostat I bought because I couldn’t
separate the old thermostat from the housing. I’m pretty sure it’s a pressed fit and it wasn’t coming apart easily so I just bought a combination thermostat and housing Maybe when I get in a mood I’ll try to separate the old parts just for the fun of it.
One disappointment was I couldn’t use the Delco thermostat I bought because I couldn’t
separate the old thermostat from the housing. I’m pretty sure it’s a pressed fit and it wasn’t coming apart easily so I just bought a combination thermostat and housing Maybe when I get in a mood I’ll try to separate the old parts just for the fun of it.
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Today I installed the new 186 degree thermostat and took the car out for a 20 mile run The outside temperature was 49 degrees. Water temp went to 192 very quickly and stayed there. Oil temp was much slower to rise but it got to 199-202 and stayed there. Considering the outside temperature, I’m satisfied with these temps. Seem pretty normal to me. No knocking or hesitation.
One disappointment was I couldn’t use the Delco thermostat I bought because I couldn’t
separate the old thermostat from the housing. I’m pretty sure it’s a pressed fit and it wasn’t coming apart easily so I just bought a combination thermostat and housing Maybe when I get in a mood I’ll try to separate the old parts just for the fun of it.
One disappointment was I couldn’t use the Delco thermostat I bought because I couldn’t
separate the old thermostat from the housing. I’m pretty sure it’s a pressed fit and it wasn’t coming apart easily so I just bought a combination thermostat and housing Maybe when I get in a mood I’ll try to separate the old parts just for the fun of it.
enjoy
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