Cadillac Seville / Cadillac Eldorado Forum Discussion, Strange Day with My Eldorado in Past Cadillac Vehicle Discussion; What a strange day today was. A little background first; about a month ago, mid-November, I got a "Check Coolant ...
What a strange day today was. A little background first; about a month ago, mid-November, I got a "Check Coolant Level" message on my dash. So I checked, and it looked like the reservoir was nearly empty, so I bought some Prestone Gold Pre-Mixed and poured about a quarter of the bottle in, until the coolant level was at the crossmember inside the tank. Everything was copacetic until about two weeks ago, when the message came back. This time I did not fill - I kept an eye on the temp gauge and drove as normal.
Now, being nobody's fool, I had been paying attention to my car since that first message. I noticed a rough idle on cold mornings (sub 30degF, mostly) - it's hard to explain what it felt like, but the tach needle would jump a hair every so often when stopped in Drive, and the car would give an ever-so-slight jerk forwards. If I held my foot on the gas a little, the idle smoothed right out and the jerkiness left. During this whole time, the temperature gauge acted completely normal - no spikes in temp and it never got above 223 degF (I hacked the DIC to give me a digital coolant temp display last year). I also did not notice any excess of white smoke in the exhaust, but I honestly have no idea how much to expect from a N* in wintertime; comparing it to cars around me on the road, it's not any more or any less than the vast majority (including other Caddys). I also have no idea how to tell if the exhaust smells like coolant - exhaust smells like exhaust to me, so short of a side-by-side comparison, I was stymied.
This morning I took the car to Heritage Cadillac in Lombard to have a combustion byproduct and cooling system pressure test done on the Eldorado. The cooling system pressure test came back negative, although the technician said his kit detected "trace, small" (exact words) of CO in the coolant, which was also low. He then told me he found the leak - a hose coming off the interior side of the reservoir had a loose metal clamp, which he then tightened. Sure enough, there was coolant (or something moist) underneath the tank on the interior chassis of the car and some of the components (not electrical) directly under the hose. So, fine, and since it was there, I also had him clean the throttlebody out, and he came back and said there had been a decent amount of gunk in there, coupla years worth at least. The mechanic suggested that I take the car back out, drive it around for a few days, and return if the coolant message came back or something else went awry.
After about 45 minutes of regular driving (some decent passing and one onramp push - nothing extreme like a WOT though) and no coolant message or temp spikes (the car was already warm so I didn't expect - or detect - any rough idling), I parked at Dominoes in Naperville and got a sandwich for lunch. Just as I was about to shut the car off, I got the "Check Coolant Level" message. I turned the car off and gave it a walkaround, and sure enough there was dripping underneath the engine compartment, right where the reservoir is located. Cracked open the hood, and yup, there's coolant dripping from the same damn hose again - and it's not just dripping, it's running like faucet got kicked on real low! That damned technician must have missed something. Also, Yikes!, that had never happened before - never saw any kind of steady drizzle from under my car except when it comes out of the carwash, and never noticed any coolant puddles like the one that was now encircling my shoes.
I get in the car again and set out to the dealership once more, after calling to let them know the situation. I made it about three quarters of the way there - in stop and go traffic, I watched with horror as the digital temp readout climbed steadily from 190 to 240. When it hit 242, I pulled of the road and shut the car down in a parking lot. I got out, opened the hood (after putting on safety goggles because I'm not sure what to expect), and saw what looked like a coolant lake under the car, steadily growing from below the coolant reservoir. The inside of the engine compartment near the leak is sprayed with coolant as well, and the shit is getting all over my shoes. I call Heritage again, and explain that I am two miles away and my coolant is jettisoning with gusto all over my shoes. He says to let the car cool for 15 minutes and then hurry over. I wait until the temp readout says 180, then open the reservoir fill cap: empty, no surprises there. As I pour in coolant, it drains right out almost as fast.
With the traffic on Finley Ave. starting to clear, I decide it's now or never. I hop in, start her up, and take off down the road. I'm trying to coast as much as possible, giving her a gentle kick at the top of the small inclines and using momentum as much as possible. I'm racing against the needle and winning, but barely. I pull into Heritage and shut the car down - the last reading was 250 degF - and immediately open the hood. The coolant is still dripping out, though most was lost en route. I know the N* has a limp-home mode, but fortunately the needle never got into the red zone on the gauge, and it didn't activate. The car also did not get hot enough to reset the oil-life indicator, though twenty more seconds of operation and the ballgame ends differently, I'm sure.
Anyway, they get her into the shop and start fussing over the coolant reservoir. The tech comes back with the reservoir in hand, and points to a small opening (nipple, I suppose) on the outside of the tank, where the formerly loose hose had once been attached. The entire nipple assembly (giggedy) was cracked open, and parts of it looked like crumbled, cracking rubber - perhaps the hose was beginning to melt as well? Anyway, they replaced the entire tank, gave me a new hose and new coolant free of charge, and I also opted for an oil change (the monitor was below 30%, and the last one was over 4500 miles behind me). And though I am perfectly capable of changing my own oil, I hate working on machines when it's cold outside, be they cars or lawnmowers. I can make an exception for snow-blowers.
In conclusion, I want some impressions. The car is running fine again - drove another two hours in stop-n-go traffic (with a few hard passes) with no temp spikes, no temps higher than 223, and no visible coolant loss or warning messages. First, how likely is it that the positive result from the combustion byproducts test was faulty? The car runs perfectly fine, and when the technician changed my oil, he detected no coolant contamination (another reason I had them do it now - all I know about contaminated oil is that it's supposed to look like a milkshake, but are we talking a McD's crapola or a Wendy's Frostie? These things I don't know.). Until today, when the reservoir failed and the coolant was jettisoned, the car has never even approached overheating - not on WOT, not on daily driving, not on long highway trips, and all of these are recent history. Even when the coolant level was low (producing a warning message on the dash), the temperatures never spiked or anything. The car did run an average of 4 or 5 degF hotter when the coolant level was demonstrably low (like after having the message come up a few days in a row), but I assume that could be normal since the cooling system was trying to do it's job with less available coolant as a heat sink. Hell, even when I was losing coolant rapidly today, the temp never really "spiked" - it would climb steadily, but never rapidly, usually 3 or 4 degrees per 90 seconds of driving with the catastrophically failing reservoir.
Second, why did they make the frappin' reservoir black? How the Hell am I supposed to see in there?
Third, are there any other indicators of a failing headgasket aside from the ones I've noted so far? The only symptoms I've had are loss of coolant and rough idle on cold mornings. I'd like to think it was a slowly failing coolant reservoir (with an apparently not-unheard-of problem with the nipple junction [giggedy]) and a dirty throttlebody. I'll know more tomorrow morning when I start her up again to check the idling conditions after a cold soak courtesy of Ma Nature. No temperature issues at all, despite the full range of driving, WOTs and stop-n-go traffic aplenty. These could be explained by a leaky reservoir and a dirty throttlebody, right? The only sticky wicket is the positive result on the combustion byproduct test, and the tech called the amount of gasses detected "small, trace amounts" and mentioned only carbon monoxide by name. How likely is it that this is a false positive and can be dismissed for now?
Any help, advice, or commentary is appreciated.
PS - I spoke to Brad at Wick Automotive in Rockford, IL, this morning while waiting on my first visit to Heritage Cadillac. He seemed skeptical that it could be the HGs, and said the Check Engine (SES) light should come on if this was the case. This was repeated by the technician at the dealership. Anyway, Wick Auto is the only shop in IL listed on NorthstarPerformance.com, Jake's website, as having been certified in using the Suregrip stud kits he manufactures. Has anyone ever used Wick Auto on this forum, and if so, could you share the experience?
It's an internal combustion engine, sealed by any number of various gaskets. A "small, trace amount" report is nothing to obsess over.
Your coolant tank is no more or less strange than several similar posts over the last few years. Plastics lose their "plasticizer", get hard, and break.
My, and other OEM reservoirs, is/ are black on the top, translucent on the bottom half. The coolant level, cold, is just at about the seam between black/translucent. Is there an arrow molded into the side of the reservoir which points down to the seam ?? That's your cold coolant level.
Automobile(s): White Diamond '03 DHS (with DTS floor shift)
Re: Strange Day with My Eldorado
I agree. Stop worrying and don't loose any sleep over it. If there was no leak, that would be a different story, but you (they) found a common problem causing the leak and overheating and fixed it. Case closed.
Got it guys. Thanks for the advice. And thanks for sticking with that tremendously long post - I just re-read it and . . . wow.
You're right, I'm getting a little paranoid. But it's a Northstar, and to me a little paranoia is justified. I will dial it back though - I'm just gonna drive it like I always do and pay closer attention. I'll check fluid levels more often, rather than waiting for the "idiot alarm". I check my oil almost weekly - I burn about a quart between changes, but I heard that's fairly normal. As for your suggestion Sub, there is no dividing line between plastics - it is a coal mine from top to skinny bottom.
It's full now though, and I have a plan: Sharpie and a skinny wooden ruler. Stick the ruler in until it dips about three inches or so into the coolant, then make a mark on the scale where the ruler inserts into the filler neck. Then mark the ruler at the wet spot on the other end - I'll be able to chart any leaking on the regular (as long as I check it at similar temperatures) by how far below the previous mark the wet line is. Or does that tank only fill at a certain temperature?
Actually, that's one reason I'm sorta paranoid - I'm not totally clear on how the cooling system works. When does that tank fill - at high temps, low temps, etc? My experience with engines is limited to fixing lawnmowers and chainsaws, and in 11th grade my auto shop elective was to take apart a running engine, catalog the pieces, clean it, and put it back together. Mine ran again afterwards, but my shop partner worked on dirtbikes as a hobby - my credentials consisted of Frankensteining a lawnmower back to life for two more summers.
If I sound pretty clueless, I apologize. The details of the cooling system in a N* is a major gap in my knowledge.
The tank should be half full, cold. The tank never "fills": it always has airspace over the coolant. That's the "spring" which allows coolant to expand and contract with temperature changes. If the tank were entirely full then expanding coolant will blow out the cap pressure release until the system pressure drops, the coolant continues to expand, and coolant blows off again. The engine will create its own airspace regardless of how much coolant you try to keep pouring in. This phenomena is NOT caused by overheating - it is caused by normal coolant expansion in an overfilled system. The reason we now have divorced reservoirs instead of a tank on top of a radiator is that the reservoir is just that: a reservoir. It stores expanded coolant and feeds it back to the engine when needed, and also acts as a container for air and gasses purged from the coolant in order to decrease water pump cavitation (low flow efficiency).
Look down in your tank, cold. If it is properly filled then you should see coolant about halfway down. Forget the ruler, forget how much it expands to when hot. Put the cap back on, tight, and drive the car. Check your coolant level only when cold, and do not add any if it's close to what you saw a few months ago. The cap has not been off the reservoir in my STS since 11/2007. It was filled correctly then, and it's still filled correctly now.
BTW, if your tank is full ("full to the top ???"), cold, then you must remove coolant until it's half full.
Sub - sounds like your cooling system is in top notch operation - 11/07! Wow! Lucky the newer platform cars have a translucent resevoir (well the lower 1/2).
Corsa - Brad over at Wick Automotive seems to be a very reasonable guy and from what we've heard he's got a good reputation. He's a former GM tech who decided to start his own shop.
Over my Christmas/New Years holidays, northstarperformance.com will be improved and updated. No time until then to finish building it. I don't like to hire anyone to build websites for me. I like to design things myself and if I know how it's built, I know how to modify it as well. My apologies to all that it still has dead links and blank pages.
If the time ever comes where your HG's need replacing, if Brad doesn't have the time I will be more than happy to help arrange shipping somehow over to my shop. Chicago is only about 7 hours away, give or take. I haven't been out there in just over a year. I miss driving through the states. Non-stop 80 MPH, open freeways.... I feel a road-trip coming on....I'll make an exception and do your HG's on site.....
BTW, if your tank is full ("full to the top ???"), cold, then you must remove coolant until it's half full.
No, not full to the top - I've been reading these threads like crazy and I know not to do that. The last person to fill it was the mechanic at Heritage Cadillac. He has the level at the same place I'd been putting it. When the leaking started, I was careful to fill it where I estimated the halfway mark to be - about halfway up, maybe a half inch under a small, metallic looking stanchion running across the inside of the tank. I always filled it cold - mainly because the cap is marked Do Not Open Hot.
I guess I probably should have known most of what you wrote down, but reading it again sure set off a lightbulb in my head. Thank you for that. I was thinking of my old cars which had their tanks on top of, or right next to, the radiator. I dunno, I knew the cooling system was important but I didn't realize my ignorance until quite recently, and my learning ability from reading the relevant threads is a bit worn down from too much office work. BTW, that engine I took apart back in the day was a 3.1 V6 out of a Cutlass. I later bought a car with the exact same type of engine. Just a shout-out to what is, IMHO, a fine piece of machinery and hopefully the most complicated thing I'll ever have to disassemble.
Jake, I would love to get my HGs done by the master himself. However, I think it's best to wait a little right now and see if any other problems develop. I still think a little paranoia is fine, but obsessing is not the correct action for me to take. If (when) they blow, you'll be the first to know. I consider the final styling of the Eldorado to be a piece of true American art, and I want this puppy running past the day my hypothetical grandchildren inherit it. Yeah, I like this car that much. I just hope they still sell gasoline in the future and we're not all driving around in giant laptop batteries or Hindenburg-mobiles.
I know hydrogen cars would be totally safe like that, but a 15-second YouTube clip of Lakehurst is enough to put doubts firmly into the explosion-avoidance part of my brain.
Corsa - no sweat. Don't fix the car until (if it ever) needs it. Best of luck to you. Next time I pass by the windy city, I'll wave if I see your Eldo on I-90 or the 294 bypass
A trucker almost made a sandwich out of my Eldo two years ago on the Chicago Skyway. I was in the left lane doing about 75 and I guess the trucker wanted to be there too - needless to say Northstar horsepower got me out of a "tight" bind....
This wasn't the exact spot but here's a photo of Chicago out the windshield of my Eldo-
Eldorados are really nice cruising cars. 80 miles per hour for the whole 1300 mile trip I took- Around 25-26 MPG, and I managed to keep my average speed for the whole trip above 60 MPH even with the stops for gas and food.
Corsa - how was your move from NY to IL? How'd you enjoy the trip in the Eldo?
While driving from Albany to Chicago, the car performed amazingly. One friend described the ride (on a different road cruise) as being in a rolling hotel room, and I tend to agree. That impression lasts as long as it takes me to pull into a rest stop, piss, and then pull back onto the highway. Hotel rooms don't go from 0-60 miles per hour in seven seconds, or leave fifty yards of rubber behind on an entry ramp. As for the actual ride to Chicago, I broke the twelve hour mark by over half an hour - I basically just went into "road-warrior" mode and loaded up the 12-disc in the trunk with my 12 favorite albums, and kept some good mix CDs up front to feed into the dash unit when I needed some variety. A Rockstar drink, two liters of water, and a Gatorade were all I needed, though I did grab a candy bar outside of Buffalo and ate a quick breakfast sandwich at an Indiana rest-stop. If you include those two stops, the actual trip time was just over 12 hours, but driving time was less.
Oh, and cigarettes. Smoked a whole pack en-route, and that empty pack is now attached to my fridge door with a magnet (things like that carry tremendous sentimental value to me for inexplicable reasons). I love having a moonroof because it prevents the car from acquiring a smokey smell so long as you only smoke when it's opened (either retracted or tipped up).