Question about 1998 Cadillac DeVille

2 Answers

98 Deville Northstar temp runs up to 240 when idle

Runs rough at startup then reaches temp around 198 and smoothes out and runs very nice. temp will run up when sitting for 5-10 min but when I go agian it comes down and runs fine. Service engine soon is on and Autozone cmptr reads elec temp sensor that I cant locate. I just bought it 2 weeks ago and it does have some white smoke that clears when it wams up so I dont know if it was condensation. It is losing about 1/2 gallon antifreeze per week. Do I have blown head gaskets? Will any leak stop work? Thank you.

Posted by on

  • clipperjay2 Nov 26, 2008

    change the sensor

  • txboifrozt May 11, 2010

    Yes you do have a head gasket leak. It might not be severe right now, but the more you drive it the more it will get worse. I have a 96 deville with northstar, and same thing you describe is same problem i had. I thought it might be the radiator, or thermostat, or heater core stopped up and the water pump. Replaced all and the temp still ran up very high. Especially on the highway. If you do not run up to any degrees near 240, your crack is still very small. Some headgasket repairs in a bottle might work. But only temporary, but can buy you time to either sell it or repair it. Headgasket is a very costly job. At first on my car i would start it up, it would rumble a lil, kind of rough, then smooth out after a couple seconds. Overheat easily, coolant spilling out the overflow constantly, and a little bit of smoke out the tailpipe and a little drip. I do not recommend on trying to replace anythingelse. These are a one of a kind, very difficult engine. Most mechanics will not even atempt to fix a northstar. There very notorious for these problems, and so hard to tear into to fix. Now you can try some stuff called THERMAGASKET.. around 100$ but if it does not work you get your money back.. and other stuff in a bottle you can get at autozone with NanoTechnology it is cheaper and you get your money back also if it does not work.

×

2 Answers

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 95 Answers

Yes it is headgasket. Mine had same problem. Yours might not be severe as of now, you can try these other solutions. THERMAGASKET... Which you can buy online, and get your money back if it does not work... And stuff in a bottle at Autozone Repair headgasket with NanoTechnology! I would try and sell it quick, because these engines are very costly to repair and most mechanics wont even attempt headgasket repair, and plus you have to TimeSert the block...

Posted on Aug 06, 2009

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Water pours out the back of the engine as fast as i put it in<br /> <!-- from fixya rte -->

Posted on Aug 11, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

Check engine light flashing check engine soon smell of gas and not running smouth


Check engine light flashing means there is a bad misfire , it flashes to tell you your damaging your catalytic converter . You need to have it check , you don't won't to have to replace the catalytic converter . Can cost up to $1,000.00 . Flashing Check Engine Light CarMD

Feb 03, 2016 | 2004 Cadillac Deville

1 Answer

98 cadillac sls idling rough


try your ful injecton you mite have a injector clogged up try seafome it mite work cant hert to try

Apr 20, 2013 | Cars & Trucks

1 Answer

'98 cadillac northstar deville engine temp up to 240 after useing bars head gasket repair---how can this be fixed ??????


Hello: You may have a stopped up radiator. A temp sensing heat sensor will tell you. Auto Zone or advance auto. Are you sure the head gasket is not leaking? Does coolant fill up the surge tank and bubble with engine running????

Jul 30, 2011 | 1998 Cadillac DeVille

3 Answers

My 91 oldsmobile 98 runs rough in idle but when driving run smooth.


Rough idle is a very common problem on 4 cylinders, but I believe the 98 Regency has a 6 cylinder in it, right?

Sometimes the coil packs get iffy, and sometimes the EGR Valve gets a leak in it causing a rough idle.

When the accelerator pedal is depressed, it can change things so that the engine seems to run smoothly.

However, I would look for codes to see if anything intermittent is occurring in the engine that may need attention.

The OBD-I scanner can help to diagnose the problem, if anything is out of specifications on the engine in question.

The owner will have to find a technician that has such a scanner.

Aug 29, 2010 | 1991 Oldsmobile Ninety Eight Regency

1 Answer

Running temp around 199 to 226 how hot should the 98 deville run


The temp. should stay within that range, but should never be allowed to run 0ver 240, if it does you have a problem

Feb 13, 2010 | 1998 Cadillac DeVille

1 Answer

2004 northstar low idle after warm up.


I FIXED IT BY NUMBER 1 : IGNORING YOUR CLAIMS OF" I CAN FIX IT"
NUMBER 2 : LOOKING FOR A VACUUM LEAK " THAT YOU NEVER SUGGESTED.

Jun 10, 2009 | 2003 Cadillac Deville

2 Answers

Engine idles rough for 90 seconds after restart when hot


sounds like the mass air flow sensor it is located on the air inlet try unplugging it and see if it runs better when it is running rough

Apr 09, 2009 | 1993 Ford Thunderbird

1 Answer

Over heating problem...


Could be a few things but either way, don't wait to have the cooling system checked out, do it now & possibly save $1000's later.
Check your coolant level first, make sure all belts are there. Rad fan should be coming on when it reaches operating temperature etc. Just bought it from who, a dealer? If it was a dealer head back to him a.s.a.p. and give him a chance to make it right, and pay close attention to what he says it is/was.

Dec 13, 2008 | 1998 Cadillac DeVille

2 Answers

Dash Board Codes


190-195 is normal temp and what codes need reset

Nov 12, 2008 | 1998 Cadillac DeVille

Not finding what you are looking for?
1998 Cadillac DeVille Logo

974 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cadillac Experts

yadayada
yadayada

Level 3 Expert

60541 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21927 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6811 Answers

Are you a Cadillac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...