Spark plugs

Tiny
CHEVY__88
  • MEMBER
  • 2001 LINCOLN TOWN CAR
  • 4.6L
  • V8
  • AUTOMATIC
  • 101,500 MILES
Car was shaking really bad when stopped at a light. Check engine light comes on when I went over 50 mph and it started bucking real bad. But it stopped when I went about 40 mph. I have changed the spark plugs and it seems like it helped a lot. But I test drove it and everything seemed fine until I stopped at a sign and I felt a small buck. Maybe a misfire? Kind of hard to explain the feeling. But it was like a small blump blump. Could not hear it just felt it in the car? Do I need to change those rubber boot things?
Sunday, July 31st, 2016 AT 4:25 PM

43 Replies

Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
Have your check engine light checked (scanned for codes at any popular auto parts store)

Write down the exact code numbers (not just what they say they mean)

Just a wild, wild guess (without the codes) Maybe your fuel filter is stopped up, the higher demand for fuel at higher speeds may not be - being met due to it being partially stopped up. Enough fuel might get through at lower speeds. Misfire codes may show up.

This may or may not be the issue. Lots of things could affect a modern vehicle.

The codes may tell a better story, bring 'em back here!

At minimum, let us know your outcome!

The Medic
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 5:01 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Well I do not really live close to town. Would it hurt the car to drive it to the auto store? And does the light have to be on for them to scan?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 5:15 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Just to add to this one I really do not know what is wrong to know if anything will be damaged by driving it. So does it just have a miss fire? If so and its not really bad you should be okay. If the light is not on it would be hit and miss reading codes with a diyer scan tool. The professional scan tools read deeper codes. So was the light on before the repair with codes?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 5:45 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
No that is the weird thing. When I got over 50 mph the check engine light would start blinking. When I dropped it down under that, the light quit blinking and has not came back on since.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 6:09 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
But changing the spark plugs really helped a lot though.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 6:24 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
With that mileage I would have changed the boots/wires as well. The check engine light flashes when you have a really bad misfire. As far as what happened after that it happened too quick and not enough information to really get a starting point on that one. You can try to see if there are codes.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 7:13 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
There was also some fluid on the driver side closest to the cab of the car, when I pulled the boot off. I soaked it up before pulling the spark plug. I want to say it looked like antifreeze?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 7:23 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Are you sure it is not oil? Did it smell sweet?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 7:29 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Kind of smelled sweet, but with oil and stuff on my hands made it kind of hard to smell.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 8:02 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Looked yellowish.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 8:04 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
So was it on the outside of the boot on top of it. Before you plugged the coil.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 8:09 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
It was a little puddle at the bottom of the boot. And it was wet where the boot seals at the top.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 9:16 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
So you think the coolant was leaking from another source or from inside the spark plug well?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 9:23 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Nothing else seemed wet besides inside the well. I did clean it up, and stuck a clean rag down the hole with the spark plug out and bumped the car over to see if any fluids came out and the rag was dry. Going to check it out tomorrow after work and see if there is fluid in it again.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 9:26 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Hopefully it is dry still.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 9:53 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Worse case scenario what would that mean?
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 9:56 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
If it was coolant in the spark plug well it would have to be the head leaking coolant in that area.
Was this
answer
helpful?
Yes
No
Sunday, July 31st, 2016 AT 10:01 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Hey I know it's been a couple days but I just now checked it and there was no fluid in it.
Was this
answer
helpful?
Yes
No
Thursday, August 4th, 2016 AT 4:08 PM
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
That's great news how is it running?
Was this
answer
helpful?
Yes
No
Thursday, August 4th, 2016 AT 8:54 PM
Tiny
CHEVY__88
  • MEMBER
  • 95 POSTS
Well I haven started it since that day I test drove it. But I started it today and it was rough. I believe misfiring alot., Car kinda shaking when it started. Had a noise with it as well
Was this
answer
helpful?
Yes
No
Thursday, August 4th, 2016 AT 8:57 PM

Please login or register to post a reply.

Related Spark Plug Replace/Remove Content

Spark Plug Gap
VIDEO
Spark Plug Gap
In­struc­tional re­pair video
Spark Plug Replacement
GUIDE
Spark Plug Replacement
A spark plug is a vi­tal part of the en­gine's ig­ni­tion sys­tem and is re­spon­si­ble for start­ing the com­bus­tion process. As a part of an en­gine tune up, spark plugs should ...
VIEW MORE