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98 sevllie 4.6 northstar


gearyp

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i have a 1998 seville sts 4.6 northstar v8, i bought this at a salvage auction it had hit a deer i had a new tank put on the radiator filled the cooling system & drove it about a mile & gauge went clear to H sprayed water through the radiator still would not cool down i checked the block temp with a infered light & it said 198 put a therometer in coolant tank it read 187 would the temp sender be bad?

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First off, you should check to see if DTC codes have been set. Go to www.caddyinfo.com, go to HOW TO, go to DTC codes and follow the directions on how to pull the codes and post them here

Since this car is new to you you need to check basics

Make sure your coolant concentration is at least 50%

Check your thermostat, it could be bad and stopping coolant from flowing

Check to see that the water pump belt is good and not slipping and that the tensioner is applying good tension

Your cooling system lets air out of the system via a purge line, make sure it flows coolant and its not clogged, if it is clogged, you will not be able to fill it all the way, air will be in there and cause the water pump to cavitate. The purge line is located at the top of the tank, NOT the overflow hose, the other hose, with the car cool, gently pull it off, start the engine and let it idle, go see the hose. Does it flow coolant?, if NOT let us know we will tell you how to fix it. If it is clogged you will overheat

Make sure your cooling fans are working

Make sure your CAP is holding pressure, remember that a system that does not hold pressure will boil at a lower temp

Let us know what you find. If all of these things are OK, you need to check the coolant for combustion by products to check for a bad head gaskets

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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also I dont recommend mixing hot parts with cold water. Could be possible the system purged and was then low on coolant

GM FAN FOREVER

Nice, clean, luxury= fine automobile

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i have a 1998 seville sts 4.6 northstar v8, i bought this at a salvage auction it had hit a deer i had a new tank put on the radiator filled the cooling system & drove it about a mile & gauge went clear to H sprayed water through the radiator still would not cool down i checked the block temp with a infered light & it said 198 put a therometer in coolant tank it read 187 would the temp sender be bad?

Possible, but not a very common failure.

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As Ranger said, yes its possible, BUT

If a TEMP sensor was bad a DTC CODE would be set, that is why I suggested checking for codes first

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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First off, you should check to see if DTC codes have been set. Go to www.caddyinfo.com, go to HOW TO, go to DTC codes and follow the directions on how to pull the codes and post them here

Since this car is new to you you need to check basics

Make sure your coolant concentration is at least 50%

Check your thermostat, it could be bad and stopping coolant from flowing

Check to see that the water pump belt is good and not slipping and that the tensioner is applying good tension

Your cooling system lets air out of the system via a purge line, make sure it flows coolant and its not clogged, if it is clogged, you will not be able to fill it all the way, air will be in there and cause the water pump to cavitate. The purge line is located at the top of the tank, NOT the overflow hose, the other hose, with the car cool, gently pull it off, start the engine and let it idle, go see the hose. Does it flow coolant?, if NOT let us know we will tell you how to fix it. If it is clogged you will overheat

Make sure your cooling fans are working

Make sure your CAP is holding pressure, remember that a system that does not hold pressure will boil at a lower temp

Let us know what you find. If all of these things are OK, you need to check the coolant for combustion by products to check for a bad head gaskets

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I see you are here, what are you trying to say with the above post?

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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when the temp sensor fails it usually wont kick the fans on ever or will kick them on constantly

* 1966 Deville Convertible

* 2007 Escalade ESV Black on Black

* 1996 Fleetwood Brougham Black on Black V4P -Gone
* 1983 Coupe Deville Street/Show Lowrider -Gone

* 1970 Calais 4dr Hardtop GONE
* 2000 Deville DTS - Silver with Black Leather and SE grille GONE
* 1999 Seville STS - Pearl Red GONE

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