So my Malibu overheated for the first time, and note it just won’t start up… Help me please.
First tell us, does it crank ok, just won’t catch and run? Or won’t it even crank?
Yes it cranks but it just won’t start
You need to test if the engine was damaged internally then by the overheating. A compression test would usually be the next step, assuming there aren’t any unusual noises occurring during cranking. You are welcome to post the compression results here, maybe somebody can suggest what the most likely problem.
If you do a compression test . . . do wet AND dry compression test, and post the numbers
By the way, is the engine spinning over WAY faster than before, but not starting?
If so, that isn’t good
No when I try to start it, it cranks slow almost like the battery is dying or something
You may have drained the battery trying to start it. Ask your shop to hook up a battery charger and recharge the battery first, before further cranking attempts.
What was the sequence of events exactly? You were driving down the road and it overheated and stalled? Or it overheated but still ran ok, so you drove it home, parked it overnight. Then it wouldn’t start the next day?
No today it ran hot out of no where, it never ran hot before. So I turned it off to cool it down, put water than it didn’t start back up, so I got it towed home and still nothing
Does this car have the 3.1 engine? These are famous for having intake manifold gasket problems. Have you been having to add coolant ? Does the oil look like chocolate milk shake?
I agree . . . the GM 3.1 and 3.4 v6 engines are well known for this
Since you were low on coolant, it went somewhere
No obvious external coolant leaks?
Check your engine oil level . . . if it’s high and looks like starbucks frappuccino, you know where the coolant went
The good news is that this is not an uncommon repair. Just about any competent independent shop should be able to handle this. There are exceptions, that’s why I used the words “just about”
I’ve heard of this GM engine problem with intake manifold and coolant ports. Just curious for anybody out there that knows, why does the intake manifold have coolant going through it? I wouldn’t guess the intake manifold would get overly hot. I don’t think there’s any coolant going to the intake manifold on my 4afe Corolla is there? With GM engines, is there some gadget on the intake manifold that operates based on the coolant temperature, and so they just decided to run the coolant over to that gadget inside the intake manifold? On my Corolla, that’s the case with the throttle body, the gadget that acts as the choke needs to know the coolant temperature so they just ran the coolant to the throttle body. Or does the intake manifold actually need to be cooled on this GM engine?
Question for OP: When it overheated, were you in stop and go city type driving, or driving on the freeway. I had my Corolla overheat one time in stop and go driving b/c the radiator coolant fan stopped working and I didn’t realize it.
@GeorgeSanJose
You’re overthinking it . . .
it’s not just GM V engines that have coolant running through the manifold
Many manufacturers do/did this
Ok, thanks for the explanation @db4690
Between the cylinder heads is a practical location for the water outlet, that is one reason the coolant passage is integrated into the intake manifold.
The intake manifold may have been leaking, ideally it is best to address leaks like that before destroying the engine.
Ok, I can see that for V type engines. Is the same true for most inline -4’s?
Not anymore. In the 1970’s and '80’s the heater hose passage was sometimes routed through the manifold of inline engines to warm the manifold and reduce emissions. With multi-port injection it is unnecessary.