Also, the coolant in the radiator is hot, and the engine oil is hot, but the hoses from the radiator to the engine are cold.. so something isnt pumping, correct?

 

Radiator could be clogged, or water pump. But I'm betting the radiator.

 

Wait a minute???
The Coolant at the Sensor is reading 51.8 Degrees F
Thats BELOW Room temperature.
Your coolant IS NOT Circulating even a little bit!
I'm afraid you need a Water Pump ... yesterday!

You can Pull and Flush-out the Radiator while you are doing the Water Pump.
TEST the Temperature Sensor (Not Sender) ... 51 Degrees? They drink Beer that cold in Britain!
You can have a Radiator Place Flush-Out the Radiator with the chemical treatment ... but, it isn't any more effective than what you can do with a Garden Hose and a roll of Duct Tape.

 

The first thing I'd do is take a Pressure Test of the Cooling System to see if there's a crack or a leak. If the System will make pressure then I'd put a Water Pump on the Car without even blinking an eye. If you do the wrenching, you can get a Water Pump on there inside of 3 Hours including breaks for the bathroom and joint rolling including twig and seed elimination.

Protect your Aluminum Heads. If you haven't damaged them yet ... quit running the car. The upper end of the systems could be getting air-bound with all that boiling through the overflow.

You'll know if you should invest in the time and effort of doing the Pump right after the Pressure Test. If the test won't pump-up the system to specs you probably blew a gasket or cracked a head by letting the alloy overheat.

Pray that the heads didn't run dry and that you only need a Pump. I'd hate to think that the Heads got twisted or cracked while you were trying to figure this all out.

That value at the Water Temp Sensor is way off. That could be a clue that there isn't any coolant in there to make it give a correct reading.

 

What's the latest on this car overheating?
What have you decided to do?

 

Well, we just put in the new water pump yesterday. Haven't done much more than that. We also did replace the plugs and wires and the engine light is now gone, but cylinder 1 is still misfiring. At any rate, I will know more today about the overheating, I just hope the water pump fixes it..

 

The water pump is now installed, Sealed some leaking coolant lines. Today Im going to try to Figure out some of the circuits i noticed that needed attention according to the Code reader I bought. Ive got an Ohms tester ill be using on multiple components. Some of the systems that came up Upon the code P0301 - Cylinder 1 misfire detected; Catalyst Monitor, Evaporative system monitor, o2 sensor, EGR. I noticed when replacing the lower intake manifold Gasket, the EGR had a horrible looking seal on it, sealed it with the Right stuff, now im kicking myself in the butt for not changing it out. Going to take that EGR seal off and buy a new one. Hopefully one of the electrical components are worn and its as simple as replacing one of them... my 2 biggest Concerns are The misfires and Engine overheating. Hopefully the new Pump should do the trick. I also was going to check the valve covers for any type of Mixing (oil and coolant) If it is still mixing im afraid the gasket is blow and cyllinders might have gone to hell. Havent driven the car much since i got the Lower intake seal changed out. I called the dealership that did the presure check a month ago and they "reccomended a new head gasket" but it wasnt acctually bad. If this doesnt clear up the problem today im going to rip that engine apart and look at those cyllinders to see what, if any damage there might be. Wish me luck... If anyone has any Ideas to what might be another good step torwards fixing this problem, any help would be greatly appreciated.

The owner~~ 99 monte 3.1L
Duncan

 

There's always a TEST to do before you wrench. In the case of the Heads and Head Gasket ... a Compression Test is in order for you.

I'd do BOTH a Cooling System Pressure Test and a Cylinder Compression Test. The Cooling System Pressurue Test will tell you if you cracked a Head ans there is a breach of the Water Jacket escaping to the Block.

The Cylinder Compression Test can tell you a number of things ... primarily, if the Head is Gas Tight and you are making good Compression on all the Holes. The possibility of Low Compression on your Number-1 Hole exhists if that is still showing the Misfire. Without good Compression, the Fuel~Air Mix isn't sufficiently compressed to Ignite and make Power.

If the Compression Test shows you that everything is OK and the Holes are all within Specs ... you can look elsewhere for the cause of the Misfire.

Done forget ... The System needs to be Re-set between Readings. Either reset the system through the Code reader or Undo the Negative Side of the Battery for 30-seconds to a minute. Be sure you have the Radio Code before undoing the Battery.

 

Ive had the Compression check done at the dealership about a month ago, they said the head Gasket was fine, the lower intake manifold gasket was what they reccomended changing. Did that. Today I checked the Ignition packs to make sure the timing was correct, everything checked out good. There are new spark plugs and cables as well so its obviously getting a spark, I ripped off the top intake manifold and noticed that the Fuel injector in the bad cylinder had no retaining clip on it, went to an auto parts store to get the clip. They didnt have it so Im going to jerry rig a Clip of my own to the top of it to prevent any leakage, I really double that was the reason for the misfire however. The fuel rail is held down by 2 large bolts both torqued in. I noticed no signs of leakage around the fuel injectors, and all plugs were secured. Im going to attempt to switch out the "bad" injector with the injector across from it, if i get a misfire in another cylinder it will eliminate the problem by showing that the injector is bad, if not, then i have to keep troubleshooting. Its alot of work but I am EXTREMELY cheap. So that covers Fuel and Spark, Air is the last one to check, I dont know how it could get clogged. I maintain my air filter fairly well. Could be an internal thing. If this fails ill get the pressure and compression check done again after i finish with this.

Duncan~ 3.1L 99 monte

 

So today I finally installed a New Fuel Injector, I suspected right, the Fuel injector wasnt working therefor causing the cyclinder not to fire at all giving me a misfire indication With the DTC code reader. Fixed that, now im getting a ?Code p0107 Manifold absolute pressure/ BARO ssnsor low Input. I forgot to plug in the component before i hooked up the battery, im hoping i can just reset it by unplugging the battery for a few minutes and restarting. Other than that i have a blow head gasket i need to fix with my BLUE devil sealant mixture i got. Hopefully the gasket isnt too far gone, If not im going to have to rip it apart >_<. That should fix the cooling issue. the biggest problems are out of the way now.

DUncan -99 monte 3.1