Last ditch effort here to try and get our car running again since we've dumped a ton of money into it now and can't afford a new car...

Our car was throwing a code for a misfire in cylinder 5. Has been for a while. It was misfiring in multiple cylinders but we replaced the coil pack that tested as bad AND the coil pack module since it was also bad and that took the misfires down to just cylinder 5.

When we got down to the head gasket, it wasn't torn so much as severely clogged up! The holes in the gasket that coolant should move through were basically cemented shut so coolant was probably finding whatever way through that it could, causing coolant to leak into cylinder 5.

We have now rebuilt the engine from the head gaskets up, cleaning all parts and replacing all the gaskets as we went. New spark plugs, new wires. Flushed the coolant system several times with distilled water.

When we finished, car started up and seemed happy! Was running really smooth for the first time in forever so I took it for a test drive. Did fine until I got on the freeway and it immediately tried to overheat. Pulled over, let it cool down and then limped it back home. Temperature gage never got into the red.

Did some research and it looked like our radiator was just badly clogged which made sense since the coolant had gotten pretty sludgy prior to us taking things apart so we replaced the radiator.

Now that the radiator has been replaced, car sounds as unhappy as it did before we started this process and is throwing a code for cylinder 5 misfiring again.

It also seems to have some trouble starting sometimes now. It starts fine if it'* been sitting for a bit but if we try starting it within like 20-30min of it having been running and turned off, it just sounds like it'* trying to turn over but won't actually catch and start. It'* not a battery issue because it doesn't make a whining sound like it would with that... It makes the same sound it normally does for like a half second or so before actually turning over and starting but now it just keeps making that noise instead of catching and actually starting up.

Any suggestions anyone has would be greatly appreciated! I'm also happy to answer any questions and will keep monitoring this thread for any ideas or questions until we're able to get the thing running again.

​​​​​​​Thanks in advance and wish us luck!

Was a compression test done? What were the numbers?

What is the history on this car?

How long have you owned it?

How many miles have you owned it?

How many miles are on it?

What maintenance has been done on the cooling system, and when?

Flow pressure from a water pump wouldn't cause coolant to bypass a good head gasket. Static pressure only builds to 16PSI, so that wouldn't push past a good head gasket either. A weak head gasket would allow coolant past, but these engines aren't known for head gasket issues.

Has it ever been overheated?

Has it been losing coolant?

How long did it idle?

Did it come up to operating temperature and stay there for at least five minutes?

Did you get all of the air pockets out?

Was the radiator actually clogged or is this only an assumption from research?

Just as a troubleshooting point: the status of the radiator and the #5 misfire are not directly related.

​​​​​​​This terminology often gets muddied and adds to troubleshooting confusion, so I'll give us a key to work with:

1. Starter spins
2. Starter engages with flexplate
3. Starter turns engine over
4. Engine catches and starts running

I do this because my confusion here is if it is "trying to turn over", is it turning over or not. If it is "trying" but not succeeding in turning over then it will never catch and start.

We're going to need more about the whining sound, and bonus points for using the key I made for us above.

Are we talking about Step 3 but in slow motion?

Sorry it took me so long to notice that there was a reply to this! I'll try to answer what I can from your post above.

The car originally belonged to my husband'* grandfather and spent a long time sitting around barely getting used.
My husband and i have had it for several years now but I can no longer remember the maintenance situation on it.

To our knowledge, it has never overheated and it has been VERY SLOWLY losing coolant for a while now, needing a top off every couple of months or so.

​​​When we started it the first time after rebuilding, we let it idle for 10min or so before I took it anywhere. It reached normal operating temp and stayed there for just over 5min before I started driving it.

The radiator being clogged is an assumption based on a few different factors. When trying to refill the coolant, we couldn't get in as much coolant as we knew it should take, even after the thermostat opened and it had been allowed to run and sit at operating temp for 5-10min and then allowed to cool back down. This combined with it trying to overheat when I took it on the freeway is what brought us to that conclusion.

No, we do not think that the radiator and the failure to start or the misfire in cylinder 5 are related. We're just not sure what happened between when I test drove it the first time and when we started it again after replacing the radiator.

In regards to your guide for starting steps, it'* getting to step 3 but not 4. Typically, it makes the noise associated with step 3 for a second or so and then step 4 happens. Right now, it'* just staying on step 3 and doesn't get to step 4.

The whining noise is not relevant now, I just didn't want people asking if it might be the battery.

I know you asked more questions but I can't remember them or can't remember the answers to them at the moment. Hopefully what I've answered here helps some.

Thank you so much for trying to help and, again, sorry it took me so long to reply!