99 Olds Silhouette Van 3.8L engine

[stregisfalls]

1999 Olds silhouette 3.4L engine FI
Question All of a sudden my cooling system is overheating. It was all functioning normal then one day the gauge shot up to about the 3/4 high temp mark, then went back downscale. The temp went back up, the dashboard vent blew cold air - no heat - temp setting was set for high heat. On the olds engine there is a tube with a brass bleeder near the water pump and another brass bleeder on the thermostat exit line. I changed the thermostat and water pump. I drained the radiator and used a shop vac to suck out all I could from the engine. I refilled the system with a 50/50 ratio of concentrated prestone and water. I replaced the radiator cap with a new one. pressure rating is 16 lbs. I started the engine and waited for the temp to come up. It came up gradually and approached the quarter temp line and was blowing heat. I opened the bleeder on the thermo exit line and air and steam came out. when fluid came out I closed the bleeder and let the engine run in idle. I opened the bleeder again and fluid and air sputtered out. when there was fluid only I closed it. I gently opened the radiator cap and heard a gurgling sound and air escaping into the overflow tank. When the gurgling stopped, I was able to totally remove the cap and replace any fluid in the radiator and replaced the cap. all this time the engine was idling. I cracked the bleeder again and more air came out. by this time both hoses were very hot so I figured the thermostat was open. more air came out and some steam from the thermo exit pipe bleeder. I watched the temp gauge and all seemed normal until I went for a spin on the road. The temperature shot up again, blower was blowing cold. I got back home and opened the bleeder. Only steam came out - no fluid. I let the engine idle and eventually fluid came out spurting with steam. I shut the bleeder and shut down the engine. ten minutes later I came back and started the engine. the temp gauge went down below the quarter line and warm air was coming out of the dashboard vents. It didn't take long for the temp gauge to go back up to half mark and cold air was coming out of the vents again. the coolant reservoir this time was filled to overflowing. I shut down the engine and waited. I cracked the radiator cap and heard a gurgling and all the coolant in the reservoir got sucked back into the radiator. This is driving me crazy - can you help me? I've read about a head gasket failure. The engine runs very smooth. My thoughts that if the head gasket is shot the engine would run very rough. there is no coolant or brownish crap in the oil. Please answer me back at [email protected] - winter is coming and I need this car! I can't afford another one. I live out in a rural section of New York State - nearest Olds dealership is in Massena NY about 50 miles away.
opcorn:

[stregisfalls]

I've been reading a lot about this engine and all the forums I've read all point to the intake gasket failing at or about 89K - 140K miles. Some intakes they say are plastic. Another forum says to replace the intake bolts with new ones - any comments?

[maxwedge]

Another upstate NY'er, Chestertown here. Anyway, the upper intake failing at the egr passage is quite common, more so than any lower gasket issues. Dorman makes an improved manifold and installation kit, Napa, Carquest has the parts as do others. I read your whole post above and I would start with a thermostat, if you still have the problem, it may be a head gasket. This can be checked with a test kit that tests for exhaust gaskets in the radiator. Both hoses hot, hmm, could be air bound also, but sounds like you bled it, the manifold problem would cause a coolant loss, same as the int. gasket. If you start the engine cold and the pressure builds quickly, sounds like hd gaskets. Pressure entering the cooling system can block circulation.

[stregisfalls]

You guys NEVER told me it would be a real tiger to take apart! When I think I got all the bolts and nuts out there's always one I can't reach or I misplaced my 10mm deep socket! I did remove the front motor mounts and I rotated the engine forward a bit. Makes getting to the backside a tiny little bit easier to get at. Still haven't found out how to get the alternator out. I got the belt tensioner out, a bracket for the alternator pivot, the idle wheel out and three bolts I still can't budge the thing. That power steering pump is a pain in the behind. AND there's an insulated pipe that comes off the exhaust that goes to something connected to the plenum. you never told me there were one bolt and a stud to remove and a doughnut to boot! Jeez!

[maxwedge]

I pm'ed you based on your recommendation from that website, the engine was a 3400, header said 3800? Correct, nobody told you anything, a site search here would have given the info if you were doing this yourself.

[stregisfalls]

OK I got the plenum out and five bolts. One is still in the head and I got to get that power steering pump out for the last two bolts. Is there somewhere I can send some pictures of what I've got? do you have a private email I could send this to?

[maxwedge]

Done, but with that web page all the info should be there. Make sure the pics are resized to fit in the email format or it locks up the computer.

[jazzabelle]

My '99 Olds Silhouette's "service engine soon" indicator has come on 4 times since I bought it used from a dealer. Last Dec.1,2006 my mechanic replaced spark plugs, ignition coil, air filter, ignition module, mass air flow sensor, & took down the tail pipe but got the wrong gasket to put it back again. Next day the right one was replaced. Next, when light came on, he tightened the gas cap. Indicator went off. My friend checked the tail pipe and found it open, not fully connected. When my mechanic checked it after it failed inspection with code PO442, he denied taking off tailpipe & said it was just off the hanger. He said the problem was the sensor in the gas tank and wants to take the tank down to replace sensor. It cost me over $600 last time. My friend checked the tail pipe again and found it not fully connected. My mechanic reset the diagnostic system & the indicator is still off.
Got any ideas? Seems like a fishing trip to me.....but what does a gal know?

[maxwedge]

Welcome to AF, 442 is related to the closed vent evap system in the fuel tank and lines, not the tailpipe. The usual diagnosis with this is looking for a leak in the vent/purge system or a possible bad solenoid, this at times can be difficult to pinpoint. BTW, you came in on an unrelated thread normally this is not recommended, start a new thread, upper l/s of page says thread starter on the forum main page.