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MORE: Engine spark plug questions
Car Engine Spark Plug Questions - This category contains featured questions
as examples. They relate to most vehicles.
Question: 1966 Chevy pickup SW step side 350 mileage: 190,000 Guys,
I've just replaced the plugs and wires on my engine and now there is a loud popping
through the left side exhaust as you look at the engine. If I leave off the
last plug, wire to the back cylinder the popping stops. Do I have a number
of wire crossed or what? It’s also been a very long time since I've worked
on an engine and I'm a little rusty. If in your answer, I need to check the
plug wires to insure they are wired right I need to know where #1 is on the distributor.
Thanks, Hutch
Answer: Do a compression check on the engine; you may find the compression
low on the problem cylinder. Obviously double check that the spark plug wires
are connected correctly. As for telling you which one is #1, that is impossible
from our vantage point. Because, on a 1966 vehicle, you can bet the distributor
has been removed and turned and the plug wires adjusted to suit the situation.
The fact that the engine runs means you must be extremely close on all the plug
wires. Just verify that the firing order is 1–8–4–3–6–5-7-2.
Question: 1999 Oldsmobile Cutlass Supreme, mileage:
75,000. I recently changed spark plugs and wires on a Olds Cutlass Supreme. Now
the car shakes slightly when accelerating. I changed each wire one at a time so
I'm sure I didn't cross a wire. It turns over and idles great. Poor acceleration
and sputtering is my problem. I put the old wires back on, but no change. I also
checked for something else I could have disconnected while working but I don't see
anything. I have no clue what I did wrong.
Answer: You may have cracked a spark plug during the install
or possibly you picked up some grease on the end of a plug while you were doing
the install. Also, check the recheck the spark plug gap.
Question: What is the difference between a hot spark plug
and a cold spark plug?
Answer: A "hot" spark plug will have a longer ceramic insulator
in the center of the plug than a "cold" one. On occasion, we have installed hotter
spark plugs in an engine that uses oil. The hotter plug burns the oil off and keeps
the plugs from fouling.
Question: 1999 Toyota Avalon mileage: 74,500. The engine light in my car
went on and the car began shaking. I brought it to a mechanic who found a dead spark
plug. He replaced the spark plug and everything seemed fine. One week later the
engine light went on with the same symptoms. Any ideas what may be causing the spark
plug to burn out? Any ideas as to what may be wrong?
Answer: Check the cylinders ignition coil, replace as needed
to repair the problem.
Question: 1999 Pontiac Sunbird mileage: 97,000. I bought this car used,
but in great shape. I was changing the plugs when I discovered one is stripped.
The person doing the damage must have threaded the old plug in with something else
in the hole, because the plug didn't blow out like it does now. It was leaking,
though, because there was carbon all over the threads and out onto the white insulator
on the outside from blow by. Problem is, it is the cylinder closest to the steering
wheel - on the backside, naturally. Not easy to see or access. Can this be fixed
without removing the head, or not? How much is this going to cost me? Have you got
an idea of something I can wrap around the threads to keep the plug in while I drive
to my mechanic?
Answer: Each repair job is different depending upon ease of
assess to the damaged spark plug hole. Kits are available for thread repair.
Question: 1997 GMC 2500 mileage: 120,000. I'm curious as to the "Auto
Parts Store" selling replacement sparkplugs. When I questioned the type of plugs
to use they sold me what I thought (as he told me) was their best plugs. After installing
them and within a couple hundred miles I found that I had absolutely no "kick-down"
output. I have heard that GM only wants the platinum plugs installed in this engine
and this is the cause of lacking performance. I am an avid snowmobiler and towing
a two-place trailer feels like towing with a Chevette. Any ideas?
Answer: If your engine was originally equipped with platinum tipped
spark plugs then replace them with OEM factory spark plugs.
Question: 1999 Honda Civic, miles: 149,000. My son rebuilt this car by
using a shop manual. The motor looks like new. He drove the car this summer and
recently developed problems. He thought he had no alternative but to buy a new ignition
distributor. It did not solve the problem. The idle is rough and sounds like the
timing is off. He checked it and the dwell and they seem ok. The plugs have some
carbon deposit on them. I also wonder why the manual list two type plugs NGK BR-6ES
for the standard engine and NGK B-6ES for the CVCC engine. He could not find the
plug so he is using the NKG BR-6ES with the CVCC engine. Is that okay? I would like
to help him figure out the problem so I started by asking you for your knowledge.
Answer: The difference between the two types of spark plugs is very slight.
The "R" in the part number signifies an internal resister inside the spark plug,
which cuts down on engine noise in the radio. Your fouled plugs are probably caused
by the "O" rings on the auxiliary valve housing in the cylinder head. The "O" rings
can be replaced without removing the cylinder head.
Question: 1996 Pontiac Sunbird mileage: 132,000. I changed the spark plugs
at 55,000 miles and had difficulty removing the old plugs. I think carbon built
up on the internal threads that exposed to the cylinder made removal difficult.
On one plug the threads in the aluminum head were somewhat damaged but I was able
to install the new plug. The car is running rough and I expect the plugs are the
problem but I am afraid of making things worse so I am looking for advice before
attempting to change the plugs. Should I change the plugs? Are there some tricks
to prevent thread damage?
Answer: Always remove the spark plugs from an aluminum head
when the engine is
cold. Try backing the spark plug with the damaged threads out a quarter a turn
and then spray a light penetrating oil on the threads. There are repair kits available
for damaged spark plug threads.
Question: 1999 Honda Accord, mileage: 106,000. After I inadvertently replaced
the spark plug wires in reverse order 4321 instead of 1234, and trying to start
the car a couple of times, I correctly placed them in order. The car started fine,
but then the engine check light turned on. I've disconnected the battery for a few
minutes to perhaps de-latch a computer lock, but it remains lit. I've also noticed
that the engine tends to idle close to 1200 rpm. According to the owner's manual,
the light indicates a fuel injection problem. What could be causing the light to
remain on and how can it be shut off ?
Answer: Scan your PCM for trouble codes and replace the failed
sensor, Then clear codes to recheck system. Sounds like the oxygen sensor might
be shorted.
Question: 1999 Toyota Camry mileage: 80,000. Hello guys, I have been able
to replace the front spark plugs easily, but do you know/or have advice on how to
remove the plugs in the back. They seem to be under the intake manifold. I can't
find any extra info in any manuals. I'm stumped!
Answer: The spark plugs are under the intake manifold or have access through
slots in the intake. Sometimes in order to access the plugs, the easiest way is
to remove the upper intake manifold.
Question: 1998 Saturn SL2 mileage: 135,000. My Saturn is missing and bucking
when I give it gas. On the thruway I have to floor it for it to smooth out. I pulled
out one of the plugs and saw a lot of oil on it. Its twin cam and plugs are in-between
the valve cover which is one piece. Could the oil be leaking through the valve cover?
Or is it a bigger problem?
Answer: If the oil on the removed spark plug was on the outside
top of the plug, you probably have a leaky valve cover gasket. If your car has not
been tuned up recently, you may be ready for a major tune-up and compression check.
Question: 1996 Chevrolet Cavalier mileage: 126,000. I am currently changing
my spark plug wires and have a problem. My 1990-1994 Chilton's manual does not match
my old 1987-1991 manual that I threw out. My old manual showed that the spark plugs
on the front of the engine were ordered 5-2-3 (left-to-right) and 6-1-4 in back
(left-to-right). The new manual shows 5-3-1 in front and 6-4-2 in back. Please let
me know which is correct? Dave
Answer: Your new manual is correct 5-3-1 in front and 6-4-2 in back.
Question: 1993 Ford Taurus SHO 3.2 mileage: 93,000. I changed my plugs
and wires the other day and found that an old wire boot had decayed and broken apart
in my plug well. I fished most of it out but a good-sized piece (1/2") fell into
the cylinder. With the new plugs and wires, I started it up to find a "popping"
from the engine and exhaust. I checked and regapped the plugs and the idle was fine.
As soon as I put it into gear the "popping" returned. When I open up the throttle,
I don't hear it but it returns at stoplights. There is a slight loss in power off
the blocks... Is it that stupid rubber boot piece or some misfire that I can't spot?
If my wires were crossed from ignition box to plug, would that be a cause also?
Answer: The piece of broken spark plug boot that fell into the cylinder
may have been caught under an exhaust or intake valve. This would account for the
popping sound you are hearing. There is a chance that some crossed spark plug wires
would also cause this problem.
Question: 1997 Mitsubishi Montero LS 3.5l mileage: 60,000. I want to change
the spark plugs, but it looks like I need to pull the fuel injection off the top
to get at the plugs. Am I missing something? 1) Is it really that much work to get
at the plugs? 2) It doesn't come with platinum plugs; can I use them since I have
to go to so much trouble to get at them? 3) Is there a cheaper manual somewhere
other than the dealer ($90)? Chilton's and Haynes don't make them for the '97.
Answer: Changing the spark plugs on the newer cars is getting more and
more difficult. You do not have to pull the fuel injection off to change the plugs.
Your car should be equipped with platinum plugs. A Mitchell or a specialty repair
book for your make of car will have diagrams and or specifications showing what
you are looking for.
Question: 1993 Buick Regal 3.8 mileage: 60,000. Changing spark plugs.
I have tried to rock the engine to access the rear plugs. Loosened the top motor
mount strap, shift in neutral. It won't swing. What am I missing?
Answer: To get the engine to move, leave the transmission in park and
use the weight of the car to rock the engine. Once it has moved, use the parking
brake to secure it.
Question: 1996 Dodge Neon DOHC mileage: 84,000. Hi guys. I was changing
my spark plugs today and when I pulled out one the old plugs, it was covered in
oil. Is this normal? I don't know too much about cars but none of the other cylinders
were like this? What do you think?
Answer: It would appear from what you described that the rings and/or
valve stem seals have failed in the cylinder with the spark plug that was covered
in oil.
Question: 1995 Buick Riviera mileage: 58,000. I need to change the
plugs on my Riviera. It's a side mount engine (3.8L V6). Any tips on
how to get to the plugs on the backside, against the firewall?
Answer: The trick to get access to the rear spark plugs is to undo the
top motor mount “strap” on the front of the motor and rock the motor forward.
MORE: Engine spark plug questions
Repair Topics /
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/ Spark Plug-2
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