What next??

[Floorman]

Ok guys, here's the story:
My 98 k1500 with 180,000 on it overheated on me. I was 2 hours from home and in the middle of nowhere. I let it cool off and limped it to the nearest place to get some water in it. Topped it off and when it started I knew immediately something wasn't right. It sounded terrible and the engine light came on. I limped it home but stopped at autozone to have the code checked. It came back as a misfire in cylinder 3.
I bought new plugs, wires, rotor and dizzy cap. Started it up and it it's still sounds bad.engine light is off but it still sound like it has a miss.
The oil looks good (not milky)
Wondering now what to look at to troubleshoot this issue.
Any suggestions would be appreciated

 

[Ironhead]

Do you know why it overheated? Did the cooling system still have coolant in it when you started to top it off? If it did, then hopefully there is no engine damage.

I doubt that a simple misfire would cause overheating. Severely retarded ignition timing can cause overheating issues, so I would check that the distributor is clamped tightly. Next, I'd check for issues within the distributor itself, specifically a cracked magnet or damaged reluctor.

Also possible that the crankshaft position sensor is not working correctly.

Of course, this assumes that basics such as fuel in the tank, fuel filter, and fuel pressure are in order.

Keep us posted on what you discover, and how you fix the problem.

 

[Floorman]

Do you know why it overheated? Did the cooling system still have coolant in it when you started to top it off? If it did, then hopefully there is no engine damage.

I doubt that a simple misfire would cause overheating. Severely retarded ignition timing can cause overheating issues, so I would check that the distributor is clamped tightly. Next, I'd check for issues within the distributor itself, specifically a cracked magnet or damaged reluctor.

Also possible that the crankshaft position sensor is not working correctly.

Of course, this assumes that basics such as fuel in the tank, fuel filter, and fuel pressure are in order.

Keep us posted on what you discover, and how you fix the problem.

 

[Floorman]

I'm unsure what caused it to overheat.
It did still have coolant in it.
Could the heat damage the spider?
One thing I forgot to add was when I put the new plugs in and ran the truck for a couple minutes I cut it off and pulled the #3 plug and it was fuel Gould pretty bad. So I went and bought another set of plugs and replaced them again..
So I don't know..
Heads, spider.?
I'm pretty mechanically inclined with older engines but computer driven ones make me a bit hesitant to just start taking things apart..

 

[RichLo]

good advice from Ironhead, start with the cheap or free stuff to make sure the truck is up to where it should be mechanically then start diagnosing more. One more thing to check or replace would be the plug wire, overheating could cause failure even if they look ok from the outside.

I would replace the cap, rotor, and plug wires because they are regular maintenance items and won't hurt your pocket book to replace them anyway, then go from there.

 

[superdave]

Don't know why it overheated, but it sounds like a blown headgasket or a cracked or warped head was the result. Need to do a compression check and I'll bet you have one or two dead cylinders.

 

[Ironhead]

Don't know why it overheated, but it sounds like a blown headgasket or a cracked or warped head was the result. Need to do a compression check and I'll bet you have one or two dead cylinders.

I sure hope the problem is not this severe for the sake of the OPs wallet. I remember reading in Road and Track magazine a long time ago that if an engine did not lose all it's coolant, it should not suffer severe damage.

For the OP, I don't know if this truck is your daily driver, but hopefully you have the time to diagnose this slowly and methodically, starting with the cheap stuff. If the number 3 plug is wet with fuel, I'd sure follow up on the plug wiring for that cylinder, and way before I decided to dig into the intake to see if there's a problem with the spider.

 

[Floorman]

It's not my dd. But it does have sentimental value. I am gonna do whatever it takes to get it back to good. Guess I'll check everything I can before pulling the heads.
Worse case I'll yank the motor and get it rebuilt. I'll update my progress as it happens.
I appreciate all the info.

 

[Curt]

Sounds like it could possibly be a stuck thermostat? Check the thermostat to see if it's functioning properly.

 

[Curt]

Also, OP stated that the oil wasn't milky so I don't think that it has a blown head gasket.