Head gasket problems?

[Trailrunner]

Hi all,

I have a 1999 9-5 Wagon, 2.3L 4 Cylinder, that I love driving and working on. I have begun to suspect that the head gasket has gone bad, and I’m prepared to learn how to replace that myself, but I’d like to be sure before I get all the way in there, especially given that I’m quite new at this and could be totally misdiagnosing the issue

Also, if it is the head gasket, what else should I think about replacing while I’m at it? (Feel free to point me to other threads if these topics are already covered). Thanks in advance!

Here’s my evidence:

1. A significant loss of coolant. The loss greatly fluctuates - sometimes it holds steady, sometimes it loses about 1 cup per 100 miles. I do have one known external leak that dumps about 1/2 cup very quickly every few weeks right when I stop driving... so that could be a large part of it

2. A significant loss of power when driving. I did run a compression test (dry, with the engine temp at normal running temp) and all cylinders are 182, 185, 185, 181

3. I checked the oil immediately after a recent drive and noticed a rust-colored sludge on the dipstick - not very much, but definitely noticeable and not something I had seen before.

4. Smoke coming from the exhaust pipe: my dad says it smells like coolant, but I haven’t been able to identify it

5. The spark plugs look good, but I couldn’t be sure if I smelled coolant on them...

6. I checked the codes on it yesterday, and got the following:
> P0507: Idle control system RPM - higher than expected. Probably due to old leaky vacuum hoses? - I have one that I know is broken
> P0502: Vehicle speed sensor “A” circuit low. Probably related to work I did on the front ABS sensor, replacing the mounting bracket...
> P1310: Ignition coil primary/secondary current sense system. A search on this looks like maybe it was caused by my cranking the ignition with the DI unplugged for the compression test?
> P1676: QDM/ODM “D” - Output 6. Not sure what this is yet

Does this sound like the head gasket? Or is there somewhere else I should start by repairing or checking?

Thanks for the help!

[Mike Brennan]

Yes, it does feel like a HG.
However three are inexpensive tests a good shop can do to confirm it.
suggest you go that route first.
A bad HG is not the end of the road. About 1000.00 to have it done. A pretty easy major job on the 9 5.
Be sure to have the head checked for warpage. An extra 100.00 but worth it.
you go too much longer you risk damaging the crank sleeves.

[Digger]

White smoke / steam/ tea kittling out the tail pipe all says head gasket. Suction side leaks don't usually put exhaust gas into the coolant and when you are sucking coolant you should have at least one spark plug that is super clean when compared to all the others. The every few weeks quick dump of coolant is probably from the engine stopping at just the right point to bleed compression out through the intake and into cooling system. This is an educated guess, but a guess none the less.

Good engine block sealers fix tea kittling more than half the time and in Albany where old cars rust like they do where I am, sealers, when they work, usually last longer than the car body. Block sealing is a one time shot, if it doesn't work the first time it won't work the second, so use the best you can find and carefully follow the directions.

This link will give you more information on HG leaks and seals. http://oilandwaterproject.org/

[Trailrunner]

Thanks for the help!

Mike - those tests sound like a good idea. If I have to replace the HG, I’m going to do it myself and learn what I can through the process, but I would prefer not to get into the project if it doesn’t need doing

Digger - that’s really interesting about the engine bleeding compression out through the intake resulting in the coolant dump... I can see how that might happen. I’ll check into the sealer option... the body is already seriously rusted (several holes), so that fix would almost certainly last long enough.