Overheating issue with steam, help!?!

[steel330i]

Ok, so back story for the issues, my 1991 318i, was making good heat/defrosting well, it slowly took awhile to become no good heat and takes forever to defrost. Next issue is I have to replace snapped belts about every 8-10 months depending on driving. Then today I'm driving to pick up my daughter and I noticed the temp gauge peg to the far right as if it stopped working...My first thought was to tap the gauge cluster, I did, the gauge responded and then 10-12 seconds later fell to the far right again...I then thought maybe a stuck open t-stat? Well I notice then a "Check Engine" light comes on and then I park to get my daughter. About 5 minutes go by, we get in and upon start up, a very rough idle, and then a plume of white behind the car(smells like coolant), I let it idle a bit and settle out, steam clears and we take off, at the first stop light I get into 2nd gear about 2000 rpms and then a bellowing white cloud of steam/white comes from the back end, cars pull over and change lanes(craziness!!!) I felt like 007!!! So I limp it home and park it, an intermittent "Check Engine" light on my drive home but no more white clouds...After about 4-5 hours of cooling off I check the spark plugs, starting from front of engine to rear ((1)white/tan tip(normal?), (2)oil/dark colored tip, (3)white/tan, (4)white/tan)...no idea what that means for the spark plugs but I feel like my car is talking to me?!? Last issue is I noticed my coolant level in the e-tank was lower than when I fixed the belts last, coolant leak? Could that alone have caused this to happen? Any and all inputs are greatly appreciated, thanks guys!

-Travis

[JohnHenryE30]

Sounds to me like a blown head gasket... Yup. Possibly damaged head and internals from you driving it further after first warning signs...

[steel330i]

Okay, I went out let car idle for about 15 minutes... Nothing?!! No rough idle or smoke or steam at all??? Is the car hiding its issues?? Safe to drive to work tomorrow??

[Geoff]

I know hope springs eternal...but once you have issues like you had, they dont just go away.    unless you click your heels 3 times...
   once these cars overheat,  just once,  bad stuff happens.  the very least that probably happened, is the head gasket went.   in all probability, the head is compromised also.   unfortunately I just went thru this with my car, which never even had the courtesy to show a hot temp on the guage,  just white coolant smoke out of the tail pipe.   the head had a hairline fracture allowing coolant into the combustion chamber.    sorry to have to tell you, but  you need get inside the engine a bit to fix this one.  if there is a bright side,  its a great opportunity to do all the things most of these cars need, redo the timing chain and associated bits, replace all coolant and vacuum lines,  waterpump and thermostat.
                                                    and belts....
                                                   Geoff

[DesktopDave]

I'm worried about the snapped belts every 8-10 months...you should easily see a few years out of belts.  I'm guessing the water pump isn't working; maybe the belt pulleys are mis-aligned as well?

So I'd be thinking about a water pump and a compression test first.  Then you or your mechanic can develop a plan of action.

[Wrench]

I agree on the head diagnosis and Dave is right on with the water pump issues.
The head needs to come off and be inspected for cracks. My theory, everything that happened up to this was putting the engine in an overheat condition and it eventually failed. Be sure to carefully observe the head gasket when it comes off. Don't clean it, just look it over for damage and a place where water could have gotten into a cylinder.

[steel330i]

Thanks a lot guys, not going in to work today so off come the T-stat and water pump for inspection, off chance anyone trust a water pump from autozone?? Thanks again

[Nelson_40]

If you can't/don't want to pull your cylinder head it would be worth it to check your oil for milkshake. Then pull your plugs to look for coolant accumulation in the cylinders & signs of fouling/deposits on the plugs. Hope it turns out to be good news or some sort of fluke, but I wouldn't bet on it.

[steel330i]

So I pulled the plugs this morning, 1,3,4 cylinders looked good, but #2 cylinder had an oil color and burn to the plug...I swapped out plugs 1 and 2 and let the car idle, after trying a few other tell tales, I'm thinking its not a head gasket but there is a leak somewhere...coolant or oil, I was a quart low(oil change less than 5k miles ago), no smoke or steam on the start up this morning, my mechanic is open on monday and I'm getting codes read soon as well...any further ideas please pass them along...btw I started the motor with the radiator cap off, I did this to see if the system accepted or spurt out the coolant(suction on system or leak) and no spurt, this led me to think not the head gasket...thanks again

[Wrench]

This is where a coolant pressure tester comes in handy. Pump the system up to 20 psi and look for leaks. I've done this and looked in the cylinder with a flash light or bore scope and watched water entering the combustion chamber showing the bad head gasket as the culprit.

That one oil fouled plug is odd... could be a number of things.

I'll offer my advice as a tech. You really really should go invest in an inexpensive compression tester and do a compression test of all four cylinders. Not sure if you've done that so here's the procedure:

Important! Pull main relay. Middle of fire wall under black plastic cover, the one on the right (passenger side) of three. This will keep the car from starting.
Remove spark plug from the cylinder you'll be testing.
Screw in compression tester hose, reset gauge to zero ( it will hold a reading until you release the pressure).
Crank engine for six compression strokes with throttle wide open.
Read gauge and write down the readings. Reset gauge.
Test remaining cylinders.

What's it all mean?
If you have a difference of 20 psi or more between cylinders, something is wrong with the low cylinder. Something like a bad head gasket or a cracked head. Sometimes you'll get two cylinders next to each other that read low. This almost always a blown head gasket, right between those cylinders. I hope it's not the case, but I'm still leaning towards the possible cracked head. Here's why.

Sometimes the crack will only open when it's in a critical over heat situation like idling for a long period of time or being in stop/start traffic. The coolant comes into the cylinder and when you rev the engine, you blow the coolant through the engine and out the exhaust in the form of steam. You might get a bit of heat dissipation during that higher rev of driving or accelerating and the crack temporarily closes. The only other place coolant can come in is through a bad head gasket OR maybe the preheat plate between the throttle body and the intake, and I would think that's pretty damn unlikely. Any of you guys that might have seen a leak there please chime in.

If you DO know all about doing a compression test, then thank you for you patience.


Good luck.

Dino

[Gabs]

I'm definitely no expert, but If your car was pluming steam out of the exhaust, water/coolant made its way into the cylinder somehow, as everyone says, either head gasket, or likely a hairline crack in the head. I would think the reason for only one spark plug showing tan/milky color, would simply mean, that's the cylinder its leaking into.

You also mentioned your oil being a quart low after less then 5,000 Miles, In my experience this sounds normal, assuming you haven't had the top rebuilt recently. I used to top up half a quart every 2500km give or take, before I replaced all the gaskets.

I would image the reason you have steam sometimes and not others, is that the hairline crack is so small that this only happens intermittently depending on the scenario, maybe even weather plays a part? Another theory to explain the intermittent-ness, and explain your belt issues. Possibly something is going wrong with the water pump, maybe obstructing it at times? This would explain why the problem comes and goes, varying coolant pressure. Also It would explain the belt issue, likely the belt would be slipping due to pump resistance, causing it to heat up, effectively wearing down its life span.

That's my thoughts on it anyway, purely speculation, as I said I'm not an expert. As mentioned above, a pressure test on the cylinders could give an indication of a head gasket leak or even cracked head.

Good Luck to you.

[steel330i]

Ok so thanks to everyone that has offered advice/opinions I very much appreciate it, when I return home from work travel tomorrow afternoon, y plan is to head to Autozone and grab a compression tester, a buddy of mine has shipped me his Peake tool that I plan to use and see what happens...My gut tells me that it's a head gasket but we will see...so my next question is this...
While I'm in the engine for a potential head gasket replacement, 1) how hard is to replace the head gasket myself? (overall comfortable working on my car but my specialty is suspension work) 2) should i go ahead and replace my timing belt and associated parts (i.e. tensioner, gaskets, etc) 3) pulleys? 4) thermostat and water pump? 5) mess under the intake?...My thoughts are if I can get it done for less than what my mechanic wants to charge me for a head gasket swap($1200) then I can justify doing the work myself and spending same money on parts and just have my mechanic machine the head($200) while its off the car...thanks again for any and all input...

-Travis

[steel330i]

okay fellas, so here's the latest and greatest...after conducting a compression test, my reading were as follows: cold --->(1) 150 psi, (2) 156 psi, (3) 154 psi, (4) 155 psi (analog gauge), normal operating temp --->(1) 153 psi, (2) 157 psi, (3) 154 psi, (4) 157 psi...this leads me to think that maybe the head gasket is better off than I was thinking it was, and that my cylinders are okay, (i.e. rings, and seals), any new ideas to confirm before I order my parts for a mess under the intake mod, new H20 pump, timing chain gaskets/seals, new t-stat and all gaskets, I'm also going to do a coolant flush, oil change, new pulleys, alt. bracket, degrease engine, new valve cover gasket, and oil pan gasket(lower)...anything else I'm not thinking of, money isn't the issue(TAX RETURN, WOOT WOOT), later fellas and thanks again...

-Travis

[d.hitchcock]

Buy a lottery ticket. The force is on your side.

[steel330i]

okay so here goes, I did a compression leak test today, to see if compression gases were leaking from the block into the coolant, and it passed the test, so my head gasket is good to go as this point...I'm thinking now that the coolant is still getting into the block but via either the intake manifold gasket or the throttle body gasket, so my determination is to do the "mess under the intake" mod...this should clean up both leak points, get rid of a few more, and  let me completely check out all hoses and clean out ICV, intake boot, afm, everything on the intake side of the motor...any ideas or opinions please let me know...I'm still going to also do my other maintenance listed on my previous post, new t-stat, water pump, vcg, new plugs, and maybe even the COP mod...later fellas

-Travis