20 Most Recent 2000 Cadillac DeVille - Page 3 Questions & Answers

Take your vehicle to a qualified repair shop as from your post you don't have a clue . And you never ever remove a battery cable while the vehicle is running . http://www.troubleshooters.com/dont_disconnect_battery.htm

Are you sure its oil? If you bought it used someone probably added Bars Leak or some other cooling system sealer which can appear as oil. Cadillac Northstar engines are well known for cooling system problems, and that is usually the first step people take. If it is oil that could indicate an intake manifold leak or a head gasket leak, although it usually results in coolant in the oil, not the other way around.

Dealer ! need factory scan tool .

You need to take them to a auto parts store and match them up.

I just had to rebuild my wife's Northstar. You have a bad head gasket. Her's was doing the same thing, and not showing traditional signs of head gasket problem. (IE: white smoke) It was just overheating with normal use.

Parts store for about $ 20 - 30

Try cleaning the throttle plate first . I wouldn't just change the IAC valve without testing , hooking up a scan tool that show engine data. A few different thing's could cause high idle .The idea is to test all thing's that could cause a high idle till you find the problem. Vacuum leaks , throttle plate sticking because it's gummed up with carbon , varnish build up . Or is the PCM/ECM making it idle that hight etc... Is the throttle cable bound up.

try this link .... https://www.google.co.uk/webhp?sourceid=chrome-instant&rlz=1C1CHBD_en-GBGB719GB719&ion=1&espv=2&ie=UTF-8#q=cadillac%20seville%202000%20owners%20manual

Throttle Position Sensor Replacement Remove the idle air control (IAC) electrical connector (1) from the IAC sensor (4). Remove the manifold absolute pressure (MAP) sensor electrical connector from the MAP sensor. Remove the water pump belt cover. Remove the TP sensor retaining screws electrical connector (2) from the TP sensor (3). Remove the TP sensor electrical connector (2) from the TP sensor (3). May have video on youtube showing how to

TAKE BATTERY TO AUTO PARTS STORE FOR A LOAD TEST PROCEDURE, MAKE SURE THE CASE IT IS PUT IN HAS THE DOOR CLOSED FOR YOUR SAFETY, BATTERIES SOMETIMES DO "EXPLODE" AND ACID FLYING IS NOT GOOD. IF BATTERY IS NOT GOOD, I WILL SUGGEST YOUR BUY AN AMPHOROUS SOLAR POWERED BATTERY CHARGING PANEL, THEY COST BOUT 30 BUCKS AND WILL KEEP YOUR BATTERY CHARGED UP OVER LONG PERIODS OF TIME.

he could be right about the heads but he may have put the thermostat in wrong and instead of opening it is blocking the coolant flow causing the overheating The time span quoted is about right for a thermostat to start opening

Try starting it and then leave the key in the on position for 10 mins or so so the computor can relearn the code.

Check fuel cap or replace.

Melvin, Recharging a cars A/C system. Check the attached links,instruction and guides, Good luck "I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info." Right Wrong way to recharge AC 2003 Escalade charging AC How To Recharge an AC System EricTheCarGuy How to Properly Recharge Your AC System

Contact a Cadillac dealer and give them the VIN. They can make a key for your ignition for less than $100.