15 Smoke/Rough Idle/Oil on spark plugs/Possibly loosing coolant. opinions?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

fatmonk8

Full Access Member
Joined
Mar 16, 2023
Posts
194
Reaction score
55
Hey all,

Back again with more issues it seems.

Noticed smoke coming from the tailpipe a while back amd though nothing of it. Since it was only a little and came out after a cold start or sitting for a couple hours I figured maybe condensation. Well I noticed it seemed to do it regardless of outside ambient temp, so hot or cold I would see the smoke. So that made me think it may not just be condensation.

Since i've had the car it had mild shakingwhen idling low, especially after it warms up. Figured it was just because it's a v8 with 100k miles on it. Went ahead and tried to clean the air flow sensor, throttle body, ect. But still had a rought idle. The idle is not so much that I was worried about ititit was just enough to annoy me.

So I decided recently to replace plugs and wires as generally maintenance and to hopefully solve the rought idle. I noticed the plugs had a little oil on the threads, not sure if that's a sign of oil leaking in or not.

I have also noticed the coolant in my reservoir is low, but I haven't had a chance to really mark it and watch it super close.

Granted I have had no codes thrown and the car seems to run fine, but the exhaust does smell sweet to me and the smoke looks white.

Any opinions? Would it misfire with no code? Could it have a very slow oil or coolant leak that could go unnoticed and cause the engine to idle rought at low rpm?
 

Tonyrodz

Resident Resident
Joined
Feb 16, 2012
Posts
31,565
Reaction score
46,956
Location
Central Jersey
I'm definitely no expert but it almost seems like you might have a leaking headgasket. Have you checked your oil on the dipstick? Also check under your oil fill plug. Does it look milky? How's the coolant look in the radiator?
 
OP
OP
fatmonk8

fatmonk8

Full Access Member
Joined
Mar 16, 2023
Posts
194
Reaction score
55
I'm definitely no expert but it almost seems like you might have a leaking headgasket. Have you checked your oil on the dipstick? Also check under your oil fill plug. Does it look milky? How's the coolant look in the radiator?
Oil looks fine. Just did a oil change and everything looked fine. No milky oil as far as I could see.

Coolant looks fine, but I could take a closer look.
 
OP
OP
fatmonk8

fatmonk8

Full Access Member
Joined
Mar 16, 2023
Posts
194
Reaction score
55
Pics of the coolant/cap, oil fill cap, and plugs. I would think what's on the cap is normal gunk from a 100k+ motor, not milky oil or foam.

20231006_103105.jpg20231006_103114.jpg20231006_103117.jpg20231006_103132.jpg20231006_103400.jpg
 
Last edited:
OP
OP
fatmonk8

fatmonk8

Full Access Member
Joined
Mar 16, 2023
Posts
194
Reaction score
55
So pil and coolant levels seem to be pretty stable since the last time I posted. Been trying to keep an eye on it.

Unless it's just extremely slow leak I vant figure out what it may be.

I will say the exhaust smells very rich to me, but I have no codes showing.
 

NickTransmissions

Sin City
Supporting Member
Joined
Mar 9, 2023
Posts
1,086
Reaction score
2,610
Location
The transmission bench
So pil and coolant levels seem to be pretty stable since the last time I posted. Been trying to keep an eye on it.

Unless it's just extremely slow leak I vant figure out what it may be.

I will say the exhaust smells very rich to me, but I have no codes showing.
Pressure test the system then conduct a hydrocarbons block test. Between those two things, you'll know if you have head gasket failure or not.
 
OP
OP
fatmonk8

fatmonk8

Full Access Member
Joined
Mar 16, 2023
Posts
194
Reaction score
55
Pressure test the system then conduct a hydrocarbons block test. Between those two things, you'll know if you have head gasket failure or not.
Have not had a chance to do a pressure test as I don't have the necessary tools or space to do so yet and haven't been able to take it to a shop.

I did do the leak test and it came back fine, no exhaust in the coolant as far as I could tell with the test.
 

THarber

Full Access Member
Joined
Jun 4, 2021
Posts
307
Reaction score
277
Your plugs are fine. Oil around the threads means nothing. If it were burning oil, the tips would have oil. Those look like a light ash color which is perfect.

You migh consider adding a catch can to the engine to help with total oil consumption.

Your coolant really doesnt show anything either.

The rough idle can be from a million things but without any codes you will never find it. Run some injector cleaner through it and a few tanks of high octane premium grand fuel and see if it runs any better.

TH
 

Forum statistics

Threads
132,200
Posts
1,863,829
Members
96,718
Latest member
1BrittanyCarr
Top