:iagree:

I don't know if there is a head gasket problem and it doesn't look like a coolant situation, but looking at the plugs there's something up with combustion. The only time you see black on plugs (these days) is because there's too much fuel - either from weak combustion or because it's dumping too much gas. If everything else is ok, oil will burn away, but crust up the plugs. Seriously doubt you'd see perfect BLM's on this car, but I've been surprised before.

Water boils at 212F at sea level. A 50/50 mix of anti-freeze and water raises that boiling point to somewhere above 250-265F or so.

Now, if you've been adding only water to re-fill after the over-flow incidents, it's possible you've diluted the mixture to where the boiling point has been considerably lowered. There's an inexpensive tester made by Prestone that can tell you what water temperature protection you have.

You could have air in the system. For an 89, the best was to get the air out is to use the packing method.

Here's how do it: I idle the engine until the temp rises to a point that the stat is open.

While it's idling I prepare a jug of 50/50 mix and place it near the radiator cap opening for easy access.

Once that's done, I reach over and bring the RPMs up to 2000/2500 or so and while holding that RPM, I slowly remove the radiator cap. Once the cap is off, the coolant level in the radiator will be low; you may not even be able to see it.

I then pour in enough of the 50/50 mix to bring the coolant level up to the bottom of the neck of the radiator and while still holding 2000 RPMs, I replace the cap and fully tighten it.

Only then do I let the RPMs return to idle.

Here are the things that I'd consider as indicating a problem:

Coolant in your oil or

White smoke out of the muffler or

A coolant puddle under the car or

Fans not coming on or

No sign of coolant flow in the radiator or

Airflow to the radiator being blocked by debris.

Off the top of my head, I suspect your fouled plugs can be traced to a bad 02 sensor. I'll bet that if you check you'll find that your system is staying in Open Loop. It can be checked with a paper clip inserted in the ALDL and watch how fast the SES light flashes.

Hope some of this helps.

Jake

West Point ROCKS!

You can buy the oil cooler hoses from the dealer, should be about $10.00 each. If it were me, I would remove the radiator and clean it out, and replace all of the hoses. Fouled plugs could be lots of things, see if you can take the car somewhere and have it scanned.
BTW, your car is '89? Have you ever changed the injectors?

one of my plugs looked like his 2 odd colored ones when I had a blown head gasket ..... pull you o2 sensor if any coolant is getting in there you will be able to tell. Or do this pull all 8 plugs pressurize system then yurn motor over and see if any coolant comes out. You will only see coolant in the oil if a lot of coolant is being put into the cylinders.

smell your exhaust when it running, you can smell the antifreeze if theres a problem.

mine always had a trickle of bubbles in the radiator cap area

Even though I had it changed annually (and I never noticed a coolant loss), mine had crappy looking coolant, noted by the Dealer during the warranty, but that's as far as they ever went with it.

My heater core was plugged up somewhere around 40,000 miles.

My aux fan was coming on - when it was new it never reached the threshold for it to come on.

The #7 plug was cleaner than the rest and there was rust on the threads (within a couple hundred of miles when I finally got serious about trying to figure out whether there was something wrong with it).

Compression tests were normal.

My idle wasn't perfect, but it wasn't any worse than I had experienced in any other fuel injected car that I owned.

After it finally let loose and teardown, I could readily see that it had probably been a longstanding issue.

I found this Forum looking for others with similar!

Yeah, I noticed the plugs were carbon fouled. I think that probably was from when I first got it, I noticed driving around it stayed at 150*. I pulled the thermostat and replaced it, and the temps went up to 200 range. No telling how long that went on for.

What is the part of the plug you look at when you look for a coolant leak? The curved piece of metal? Or the white ceramic part?

Yeah, I think I'm gonna remove the radiator, and flush it real good. I've got on order a flexible water blaster. www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96541

The PO replaced the injectors and fuel regulator. He put in Accell injectors.

Do you guys use any chemical flushes for the system? And I was wanting to remove the knock sensor so I can drain the block out and flush it real good sense there is stuff in the coolant. Could I jack up the car to remove the knock sensor? The PO gave me a brand new knock sensor with the car. I took it to a shop to replace it and drain/refill the coolant a while back. I brought in enough coolant to refill the entire system. When I picked it up, I noticed they didn't use alot of coolant. So, I figured the knock sensor hole was probably clogged.

I'll pull the O2 sensor tommorrow. What do I look for? Rust on the tip? And how are you turning the motor over? I don't know how to do that.

I put a pressure tester on the radiator today. I pumped it up to 16 psi, and watched it for 10 minutes. The car was cold. It held 16 psi for the 10 minutes I was watching it. Though, for some reason when I relieved the pressure from the tester, coolant poured out the cap area.

Just wondering. But before I did the test, I pulled the relief valve on the cap, and got a couple of burps in the overflow bucket. I haven't started the car in a week. Is this normal? I've noticed this before.

If you're getting coolant in the combustion chamber your plugs should be steam cleaned, white. Little or no color to ant of the cylinder(s) experiencing the leak.

Your plug color is on the opposite end of the spectrum, telling me you most likely have an injector(s)/fuel regulator leaking and/or your engine isn't going into Closed Loop caused by a bas 02 sensor.

A good firing plug will have a light tan or grey color and a thin darker ring on the ceramic/porcelain or whatever it's made out of. When reading plugs for the correct A/F ratio, the position of that ring (how deep in is in the shell) is what to look for. To see it well, you'll usually need a lighted magnifing glass though.

Plugs as dark as yours means something very different in going on. If it's oil then it could be valve stem seals or rings.

First check to see if you ECM had any stored code. Then get a digital voltage/ohm meter and start checking your sensors - TPS, MAF, 02, knock, coolant temp, fuel pressure regulator, ignition timing.

Time to buy a Factory Service Manual and follow the trouble-shooting procedures in it.

We can only advise you what to do, we can't make you do it. Horse to water adage.

Jake

West Point ROCKS!

When I bought it, the PO told me that he had a miss problem and replaced the injectors. And that it turned out to be the fuel regulator. So, he had that replaced too.

He also gave me a brand new set of spark plugs. Split fire I believe. So, I'm assumming he had plans to replace the spark plugs after he put in new injectors and the fuel regulator, but never did.

Those are the spark plugs that were in it when I bought it. So, I'm assuming the rich problem was from the faulty fuel regulator. And it probably wasn't going into closed loop as the temp would just get to 150* driving around. Replaced the thermostat, and the temps went up to the 200 mark or so.

Though, I'll go ahead and replace the O2 sensor, as with the previous rich problem, it is probably bad anyways. Is the Bosch O2 sensor good, or go to the dealer, AC/Delco? I already put in a new knock sensor, as the PO gave me that too.

I know the PO replaced the cat. And I don't know if 89's had precats or not, but if it did, then the PO had them removed. I later noticed there were some holes in the exhaust right after the bend at the mufflers. The pipes are rusty. I was able to brake one of the mufflers off at the rusted through spot. I had the rusted through parts of the exhaust cut out, and had the mufflers re-attached with new pipes. I didn't do a cat back, but probably should have. I know I shook out lots of crap out of the muffler.

If your injectors are the Accel Yellow Tops, they could be your problem. Also, what size are they?

85-93 Accel fuel injectors. 24lbs/hr. 150824

When I got the fuel injectors box, I pulled the two boxes of spark plugs the PO gave me. They were in an Accell spark plug box. I never looked in the box, I assumed they were new spark plugs.

But I looked at the spark plugs, and they were AC/Delco. Probably the ones from the factory. They were carbon fouled. So, the the fouling was happening before the PO replaced the injectors and fuel regulator.

I'm thinking it was cause the car didn't get up to temp when I got it, so it ran rich. I got that fixed a year ago. I'm gonna replace the O2 sensor.

I put in AC/Delco standard plugs in 3 months ago. I've only driven it 3-4 times since. I'll probably pull a plug just to see if it shows any signs of carbon fouling. I did notice the other day that the Delco plugs I put in have rust on the part you put your socket on. I don't know if that is normal.

Those are the same injectors I have in my car, and it runs great. They are not your problem.

The rust is normal.

I don't drive it much. But I will probably check the plugs once a month or so to see if they do start carbon fouling.

I'm gonna remove the radiator and flush all the crud out. Then flush the heater core. Then I plan on draining the block and flushing the crap out through the block drains. Then I'll put in a new thermostat and see if I still have the same problem.

If you have a "fail safe" stat, it is possible for it to get stuck all the way open if you have air and/or excessive pressure. There are 2 little clips that catch the valve when it opens up too far. This happened to me when I "packed" the radiator as described, which I have always done since I bought my vette in '95 and had serious overheating problems. The fail safe was a recent installation. My overheating problems were finally cured back in the day when I removed my radiator and pressure washed the fins from the outside. Tons of little grains of sand came out, which were practically invisible when looking at it. After my "fail safe" was unstuck with a screwdriver, I drilled two 1/8" holes in it to take care of any air bubbles that might blow the thing stuck open again. I also have left my rad "unpacked" at this point. My car is running right at 190 degrees which is where I like it. I highly doubt you have a gasket problem.

I did put in a fail safe thermostat. It was the most expensive Stant thermostat.

What brand thermostat are you using? I was thinking of putting in a 195 Robertshaw. They are supposed to be better flowing, and resist pressure from the other side which can cause the thermostat to close. And it is supposed to let the air bubbles pass through compared to a poppet type thermostat.

I'm gonna power flush the outside and inside of the radiator.

I believe mine is a Stant also....got it at the "zone". I had no idea that it would stick all the way open like that until I had to take it out when my car would not get over 130 degrees. Like I said, it happened right after I packed the radiator in the fall before I put it away for the winter.

Just curious. But with the engine cold, if you pull the pressure relief valve on the radiator cap, do you get any burps?

Mine does this. I pulled the valve on a cold engine, and got some burps. A week later I went out and pulled the valve on the same cold engine as I didn't start it any, and got some burps.

I believe that is a good thing Josh. There should actually be a vacuum as the coolant cools off, drawing water from your overflow tank back into the radiator. I would be worried if nothing happened when you pop the cork.