• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

fouled plug?

J

jeepnuts311

NAXJA Forum User
Location
Atlanta, Georgia
hey all,

this mornin my jeep started just fine and idled ok, but it lacks power and the exhaust sounds really weird. i have a flowmaster and it has a good sound, but today it sounds like a old V8. when i rev it up and let off, it overruns and sounds like there is firing in the exhaust.

it starts just like normal, idles a tad rough, and smells rich. do you think this is a fouled spark plug? im fixin to change them pending responses on here.

i have had sensors go bad in the past, and this isnt the same as that. the jeep tries to rev and even tho its missing badly it doesnt act like its gonna stall. drove just fine just felt funky.

-Tim
 
did it act this way after the car had warmed up to operating temp too, or only on a cold start.
 
im assuming this is a 1990 based on your profile you might want to check over by the egr and related parts that hook to the intake or exhaust also that black plastic vacume pod that is connected to the egr can melt and make a loud type of exhaust noise.good luck!
 
You can tell tons about how an engine is running by doing a plug reading. What did the plugs look like? Can you post a pix of the plugs?

My bet is on a clogged CAT, but that is pretty much a guess without seeing the plugs.
 
hey all,

just drove to work and have more symptoms to post up. it will barely go 60 mph, and there are lots of hills on the way to work. it shakes like crazy when struggling to go up the hills. if i put the pedal down it will downshift and go a little better, but still shakes. downhills it coasts like normal. it shakes a lot at idle too now. honestly, it feels like the timing is off, but i dont see how that could be the case.

old man, i trashed the plugs already, but they looked about like normal for my jeep (black, but not corroded, and the tip of the plug has a little white fuzz on it)

yes, its a 1990 with a quarter million miles on it. it ran fine two days ago. its got terrible compression, and tons of blow by.

-Tim
 
A quick test for a plugged cat is to take a hacksaw and cut the exhaust pipe in front of the cat. If the cat is bad, your problems should go away. If it is not the cat, you can always slip a union over it and finish it off with a couple of muffler clamps.
 
old man,

after work i cut the pipe in front of the cat and dropped the cat. it is so freakin loud.

but, the problem is definitely still there. it is really loud so i cant hear anything, but it doesnt have the power it used to and it is still shaking up hills and under throttle. under steady throttle it cruises ok..

-Tim
 
old man,

this mornin, the jeep started out runnin like balls again, but then after a few miles it straightened up, now its runnin like a champ.

the cat was hella clogged tho. i dumped a pile of junk out of it that looked like ashes and gold flakes lol. it was pretty solid, and noise doesnt travel thru it.

what plugs cats?

thanks

-Tim
 
Running too rich tends to clog cats. The other thing is the matrix inside crumbling.

Since it itsn't the cat and it comes and goes, my bet is on a bad O2 sensor or MAP sensor. Both will royally screw with the mixture.
 
old man,

i am guessing it was the cat, because the jeep is running great today. its got more power and smoother accelleration than it did before. it is kinda weird that it ran like crap for about 10 miles after the cat was removed, but i drove about 100 miles today and it ran perfect...but my alternator died...these repairs always come in bulk. it will run perfect for a year and then 10 things go at once. last sunday it was the radiator. when it rains it pours.

-Tim
 
The computer was probably taking its time to relearn the operational parameters.
 
You must log in or register to reply here.

Similar threads

N
New Engine is Hard to Start
Replies
0
Views
34
NGThomas
N
R
1992 XJ AW4 doesn't want to shift
2
Replies
20
Views
3K
Rob Mayercik
R
M
2000 cherokee chk eng light
Replies
11
Views
1K
XJI6191
X
G
Engine low on power
Replies
7
Views
2K
Gotitjr
G
9
Renix lowish idle
Replies
10
Views
1K
90xj06
9
Back
Top