oldsmobile forums   oldsmobile forums

Go Back   Oldsmobile Forums > Most Recent Oldsmobile Models > Oldsmobile Intrigue

Oldsmobile Intrigue Forum specifically intended for Oldsmobile Intrigue based discussions.

Oldsmobile Forum: Strange, strange, very strange. Intrigue 2001
Thread Tools
Old July 27th, 2018
jfaatz jfaatz is offline
Junior Member
Join Date: Jul 2017
Posts: 5
jfaatz is on a distinguished road
Strange, strange, very strange. Intrigue 2001

Love this car. Long story here. Been working with this issue for some time trying to figure it out. Talked to mechanics, read forum threads, now I have to just ask you.

Cooling system well filled. Start and run engine (3.5), all goes well until thermostat begins to open then air or coolant(?) starts feeding back up from the thermostat via the supply hose from the coolant recovery tank causing the appearance of boiling in the tank. The engine is NOT overheated, it hasn't even reached operating temp yet. This condition continues while the pressure in the tank proceeds to push the coolant out the tank overflow. As this continues, the coolant is depleted and eventually the engine starts to overheat. This all takes approx. 8-10 min. before it needs to be shut down.

Compression is good on all cyls. Last week I had my mechanic check for exhaust gases in the coolant. Negative. I have removed all components except for the crossover unit and checked for blockage. Negative. New thermostat and tank cap. No coolant leaks anywhere. I have tried to read this systems mind but it refuses to think so that doesn't work.

I have not taken the temp. of the coolant as it starts this "boil" but I can't imagine that it is overheated since the temp. gauge is reading low.

Any input on this dilemma will be greatly appreciated.
Reply With Quote

Old July 27th, 2018
Cutlass350 Cutlass350 is offline
Senior Member
Join Date: Aug 2012
Location: New England! :-)
Posts: 653
Cutlass350 is on a distinguished road
It sounds to me like a bad head_gasket.

>Last week I had my mechanic check for exhaust-gases in the coolant.
Was it at a Dealership? Most local mechanics do things the fast, quick, cheap way. That's because that is what 99% of the people want. If they did things like the dealership (methodical, detailed, involved), they would likely go out of business.

Fwiw, a good LX5 engine can run a car in 110F heat, in the bright sun, in the day, in a desert, with AC running, going 55MPH, with zero coolant, and not overheat.
That's what GM did for this series of engine as a demo.
Yes, amazing technology! Too bad, GM did like it always did, and purposely designed a cheap head that often fails (to save money, and make more profit).

Head gasket failures can be very hard to diagnose and verify on LX5s engines.
There are many ways to test for exhaust_ gases in the coolant. A dealership should do it the best way. However, even with the best exhaust_ gas in coolant tester, iirc, at least 25% of the engines with bad head_gaskets will test "good".

There are many ways to test for a bad head_gasket. A problem with the way that the LX5 head_gaskets often fail, is that the failure can be very temperature/load/etc dependent.
In general, a leak down test is one of the best ways. That is down with the engine off. So, again, the gasket may seal by the time the cylinder is tested.

Another way is for the technician to shut off cylinders one at a time. The GM Scan tool can do that. That may identify the bad cylinders. Then, the spark plugs could be pulled - and looked at, a leak-down test performed on those cylinders, and an inspection scope put into the cylinders to look for signs of coolant intrusion.

Yea, there are a lot of things that can be done. That takes time. Time is money.

For local garages, people do not want the mechanics doing $300-$500++ worth of diagnostic tests, just to tell them that their engine is worthless. Again, that's a great way to loose customers, get a bad reputation, have people go on yelp/etc and YELL THAT MECHANIC/SHOP IS RIPPING PEOPLE OFF AND **STAY AWAY OR THE WILL STEAL YOUR MONEY!!!!***

So, again, I suggest going to the Dealership, and be prepared for real the cost to get real/good/proper diagnostics tests.

Other than a local garage getting lucky, of the engine "breaking so that the failure is more obvious", imho, there's not much choice.

Fwiw, when the head gasket went on my engine, it was a learning experience. I noticed it because the coolant temperature would be "a little to high, but within normal" under some common circumstances. I brought it to my local mechanic, that I knew and got along with very well, and had them test the engine. They didn't see anything (compression tests, cylinder balance tests, look at spark plugs and scope cylinders, etc).

After a few weeks, I had some time. I spent a good portion of my weekend doing engine tests. I have a GM scan tool. I eventually found a test that indicated a bad head gasket. I forget what it was and the details.

I brought the car back to my local garage, and talked to directly to the mechanic that would do the test on my car. He used to work at a local GM dealership for many years. I told him the tests I did, what I found, and why I thought that test XYZ showed a bad head gasket.
He repeated the tests, did some more testing, and verified that I did in fact have a bad head gasket.

In my case, I actually trusted him more than the dealership, since they knew me, and my background. I'm not a GM car mechanic guru. I know a lot. But, that is not my job and something I do every day.

If I go to the dealership and tell them I did some tests, I might as well be talking to a wall. <rolleyes>
Yea, ignore the fact that I've rebuilt a number of engines, done a ton of engine mods over the years, know a lot more about some of the control functions than they do, modified man cars over the years, etc.
But, again, I'm not a mechanic.

Good Luck!
Reply With Quote
Old July 28th, 2018
jfaatz jfaatz is offline
Junior Member
Join Date: Jul 2017
Posts: 5
jfaatz is on a distinguished road
Cutlass 350

Thanks so much for your lengthy reply, personal experience and advice. Well taken. jfaatz
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -4. The time now is 07:12 AM.

cars connected social network

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
oldsmobileforums.com recognizes that "Oldsmobile", it's logos and various model names and numbers are registered trademarks of the General Motors Corporation. These terms are used for identification purposes only. oldsmobileforums.com is not affiliated in any way with the General Motors Corporation, Oldsmobile or any other company listed herein. All information on this site is the opinion of its members and not the opinion of the site itself. ©2017 oldsmobileforums.com. All rights reserved.
Need products for your Oldsmobile? Check out your options at the links below:

Miss that Olds 442? Believe it or not, Kia may have something for you. The Kia Stinger is a large sport-oriented hatchback sedan in the mold of the Audi A7.