billthe3

At least I now know what is causing my funky engine temps.

Anyway, went to go borrow some timingbelt tools from Steve (Kuhl951) and while I was at his place we did a compression check on the car. Dry I got cylinder 4: 152, cylinder 3: 152, cylinder 2: 154, cylinder 1: 111. Retested cylinder 1 with some oil and got 120. (cylinder 1 = front of the car)
**edited to correct cylinder numbers**

The car only has 85,800mi on it and there were no signs of the #4 plug being fowled or coolant in the cylinder. However the temps on the engine fluctuate all over the place as I'm driving, and if I sit for a long enough period at a stop light the temp will start climbing into the red line on the temp gauge, but I always get moving or turn it off before it gets any hotter.


So, do you think that this is a bad gasket, or could it be something more serious like valves or piston rings?



If it is the gasket, would you recomend getting a stock one or one of the widefire gaskets from paragon? Also, could I get by with only buying the gasket itself or should I go ahead and buy their gasket kit and do all the gaskets in the head?

Also, since the head will be off would this be a good time to do new headers? What else should be done now as well? I already have a large pile of parts here as I was about to do the timing belt and water pump, but since this has come up I'm going to wait to do those till I do this as well. I'm thinking while I'm tearing into the engine I should redo all the vacuum lines, get new plug wires, and try to clean up the engine bay a little.

Anyway, any suggestions about the situation or the work required for replacing the gasket is greatly appreciated! Thanks in advance!

special tool

Go out for a drive and warm up the car
When you get home, mark the water level on the exspansion tank with magic marker.
Let the car cool off for 10 hours.
Mark the level again, it is now lower.
Now go and drive for a long time - no boost, idle and cruise only.
Did you lose any water?

billthe3

Ok, I'll try that and post results. (will stick those here after I've done that test)

Isn't it possible to have a gasket leak that only lets exhaust gases out into the coolant but not coolant into the cylinder?

Ski

morn'n tool.

If you're not loosing water, after you do what tool said, thermostat or complete pump.

special tool

No. This is why you are testing with no boost - vac only (idle/cruise).
Under vac a leak into #4 water passage will pull water INTO the cylinder



Mornin' Ski

DrZ1

I am going to pick up my car today w/ similar symptoms, except the loss of comp in cylinder 4. I was losing coolant and did not find a leak until after a freeze, which showed it coming from the water pump, Must have been leaking before under boost. My water pump was not only leaking, but as you turn it by hand it was excessivly noisy, may want to check all aspects of cooling sytem including bleeding for air.

btw how does it run?

Steve

Tom M'Guinn

Also try a cooling system pressure tester (available at Sears). The cooling system problem may be as simple as a undetected leak -- and unrealted to the lower compression. The fluctuating temps probably mean you have air in the cooling system -- either from an external leak or from a HG leak. If the temps come down when you start moving, it's probably not the t-stat. Also, try putting the overflow line in a clear plastic bottle (16oz Diet Coke is my choice) and see if you (a) get overflow when driving hard on boost, and (b) get no overflow when driving easy. See my HG write up under my sig below. If you have to pull the head, I'd get the valves refreshed either way, since they have 85k on them anyway. Widefire gaskets are considered an upgrade (I use one), although honestly I'm not sure anyone can prove the seal better/longer. The HG kit makes things easier -- you will need the intake, exhaust, and cam tower gasket at a minimum, so might as well get the kit.

Techno Duck

Run the car up to temp and shut it off, then let it sit for about an hour or so. Do you get a misfire on startup? With the cooling system pressurized from the heat, it will leak coolant into the cylinder. This was happening to my car when i had a blown headgasket (though it was on my n/a). If the car does run rough... shut it off immediately and take the spark plug out, the plug will probably look wet. Also if you look into the cylinder with a flashlight you may see the ominous green of coolant sitting on top of the piston.

gregeast

Bill,

Sorry to hear of your problems. Maybe I missed another thread, what kind of symptoms are you seeing with your 'funky temps'?

billthe3

Very sparatic temps while I'm driving. Over the past month or so my average driving temp has gone between the second and third white line to always right below the third white line as of late. When I come to a stop at a light or whatever the temp will quickly start to rise up to and into the red, but I start moving or turn the car off before it gets to that point. I noticed the other day as I was coasting down a hill that once I let off the gas the temperature went down to almost the second white line, which is the lowest it has been in a long time, but then once I had to get back on the gas as the hill ended the temps shot back up again (my thinking is coasting wouldn't have the pressure to force air into the cooling system).

I know the fans are working and my coolant level does not noticably change, nor is there any rough starting. There is a small amount of oil on top of the coolant in the expansion tank, but it sounds like thats just the normal oil there from the turbo system or whatever it is that puts that there. When we pulled the plugs to do the compression test the cylinder 4 plug looked the exact same as all the other plugs - I'll take another look at them tomorrow though. No leaking coolant that I can see on the engine; the only thing left on the ground after parking the car is a small amount of power steering fluid.

So really the only symptoms I have so far are the low compression numbers for the cylinder and the overheating problem. The rate that the overheating problem has increased recently has me worried to drive the car much without getting in there and fixing this.

hosrom_951

Hesitation on cold start ups and white smoke also indicate a bad headgasket.

sly_alex

it can be a problem with the calorstat which is located in the water pump

reno808

I my car i dont have oil in my coolant. I could be the coolant or a bad waterpump. When you start and or run the car can you see white smoke and or smell antifreeze?

lejams

"So, do you think that this is a bad gasket, or could it be something more serious like valves or piston rings?"

I had a burnt valve on #4 and there was no question what it was when it happened. Started missing like hell, considerable loss of power, and barely limped home.

If you have access to a boroscope, you'll answer allot of questions before taking things apart.

Here's one reasonably priced I thought about picking up. It sounds pretty good, but if the quality is sub-standard, it can be returned. http://www.griotsgarage.com/search.j...text=boroscope

lejams

"4 plug looked the exact same as all the other plugs"


Typically water in the chamber will clean a plug. It's possible you have two issues, the water pump / thermostat causing the temp problem, and low compression a separate issue.