Diagnosis? Checked threads no answers....

Tony0991 · Jul 13, 2014

So I have a 2G 99 with the 2.0L. I was driving home last night and found out the cooling fan wasn't working, so I tried to limp home. As long as I was on the highway it was fine, got into town and it started to overheat so I shut it down and pulled over. I checked the radiator fluid by releasing the drain at bottom and it looked fine. Then the oil was next, it too looked just like when I put it in. I went and got a pressure tester that hooks onto the opening the radiator cap sits on. I applied the pressure and it slowly dropped. Makes me think the head gasket is out. No white smoke coming out of the exhaust. There is white smoke coming out of the vent tubes in the top of the cam cover. It is sluggish in first gear and has a very low idle. (usually idles about 1500-2000 rpm.) once I get up to about 2000 rpm everything is fine. I don't want to just go tearing into the engine but I'm lost as far as a diagnosis. I've had some people say I blew piston rings and need to replace, others say head gasket, and some say the motor...... Please any answers or theories would be appreciated. I will end up draining fluids tomorrow night and digging into the motor if nothing else.

Tony0991 · Jul 13, 2014

Fixed the cooling fan btw. It was the relay.

4everboosted · Jul 14, 2014

Get a compression test kit. Compression test each cylinder. The cylinders will not all be the same, but don't worry that's how its supposed to be but they should be relatively close. If one or more is far lower than the others, get a leakdown test kit, so you will be able to diagnose a headgastket, valve issue, bad rings, cracked block etc.

NHerron · Jul 14, 2014

You're getting waaaay ahead of yourself IMO. You said it overheats in town. And the fan didn't work. Okay that's the problem, you even said you fixed it.

As for the cooling system pressure test. If pressure is falling it means either your tester is a POS and leaks somewhere, so spray it all down with soapy water. Or B, there is a leak in the cooling system. So check for leaks. If you can't find one right away, just keep pressure in the system and eventually you'll find one. If still can't find one, hit the key. If the starter slams on something when you hit the key... well it's your headgasket leaking coolant

ohlegend · Jul 14, 2014

NHerron said:
You're getting waaaay ahead of yourself IMO. You said it overheats in town. And the fan didn't work. Okay that's the problem, you even said you fixed it.

As for the cooling system pressure test. If pressure is falling it means either your tester is a POS and leaks somewhere, so spray it all down with soapy water. Or B, there is a leak in the cooling system. So check for leaks. If you can't find one right away, just keep pressure in the system and eventually you'll find one. If still can't find one, hit the key. If the starter slams on something when you hit the key... well it's your headgasket leaking coolant

I agree with this. Look for a leak, put some cardboard under your engine and see IF and where it is leaking. If you don't see anything, your over heating was caused by a malfunctioning fan.

Tony0991 · Jul 17, 2014

so I pulled the head off and looked at everything. ordered new valves and seals and spark plugs. pistons look great. the valves looked pretty torched though so I expect my seals are bad. I'm waiting on my coil compressor to get here so I can actually pull them out and see the seals. I was getting a lot of blow by and that's why I tore it apart. I'm probably going to make a catch can when I put it back together. Does that sound like valve seals to you guys? Or did I just pay 250 bucks for nothing....

BoostedBeaver · Jul 18, 2014

Did you ever find out where the pressure was going in the Cooling system? If not, that issue is not going away with new valves.

Did you ever do a compression or leak down test as suggested above? If not, how did you pin point the valves as being bad?

What are you considering a lot of blow by and how have you measured it?

Robert

asexton6969 · Jul 18, 2014

You should have started with the basics and not jump straight to the worst. NHerron said it best.

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Diagnosis? Checked threads no answers....

Tony0991

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