Rough idle at start, funny looking coolant.

[Spencer]

Alrighty, my truck loves to break when I get laid off, last week it was the bearing fiasco, now it seems like a bad head gasket?

So I had some mud looking stuff in my radiator so I flushed it holding it was something and not oil, well I haven't checked for the mud againt but it seems my fluid is slowly disappearing. And now I'm getting rough idle at startup.

New headgasket time?
Anything else I should get while I'm doing this?

How hard is this to do?

 

[brian2sun]

How does the engine oil look? Any white smoke out the tail pipe? Did the "mud" look like chocolate milkshake?

 

[rjaudi]

You should have white smoke from the exhaust or coolant in the oil if the head gasket is bad. You may have a bad radiator leaking coolant into the transmission fluid. Check for that as it is a common problem as these trucks age.

 

[Spencer]

Oil appears fine.

No white smoke but has always had this sweet smell in the exaust

 

[Spencer]

i check the transmission fluid and oil almost daily, never seems to get in there but i did get mud on my radiator cap and sludge in overflow container

 

[quicksilvr]

Oil appears fine.

No white smoke but has always had this sweet smell in the exaust

Massive bump. I'm worried I have some kind of headgasket issue on my '99. Here's the facts:

-Within the last 3 months, my idle has gotten just the slightest bit of roughness to it at startup. It used to idle so smooth that you couldn't tell the truck was running. Now, if I put my hand on the steering wheel, I can feel a lopey roughness (almost like it's a v8) in the idle. Again..this is a very slight roughness to the idle...RPM doesn't vary, and you can't hear it.


-When I took my trip to Colorado last week, my overflow tank went from overly full to almost empty. That was the first time I'd EVER seen coolant dissappear from the truck. Since refilling the overflow tank, it has not gone down at all. Zero. (on the trip, I pushed the engine pretty hard going up some mountain passes, and my SGII was reading 215 coolant temp for a while)


-My exhaust has a slightly sweet coolant smell to it. No smoke, ever. Just a smell.


-Last oil change, my UOA came back great. No coolant in oil. I'm changing the oil tomorrow, and will have to wait to see what that UOA says. However, the oil looks perfect right now, and I don't expect to see any coolant in the UOA.


-Coolant looks perfect. Coolant is Prestone's new "mix with any" coolant. No silicates or phosphates.






What to do? Any diagnosis help?

 

[simmonsauto]

pull the plugs, look for a clean one... pressure test the cooling system.. definitely sounds like a head gasket though. Good luck