- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
You'll need to remove the oil cap and the 6 bolts holding on the engine cover. The front 3 spark plugs are pretty easy to replace. You'll need to unplug the spark plug wire from the coil and disconnect the electrical connector. Unbolt the 2 10mm bolts holding the coil to the valve cover. Twist the coil and boot back and forth and pull it out of the cylinder head. The spark plug is down in the head, you'll need at least a 6 inch extension with a 5/8" spark plug socket, a telescopic magnet will help get the spark plug out of the head. The back 3 spark plugs involve removing the upper intake and throttle body, unbolt the bracket to the throttle body, and the bracket bolted to the upper intake manifold. on the back side of the engine. Remove the tubing from the throttle body to the air cleaner box. Unbolt anything else bolted to the upper intake. Unplug electrical connectors to the throttle body and any other electrical connectors on the upper intake and remove the upper intake bolts. And move the upper intake out of the way, there are only spark plug wires on the back 3 plugs. Twist and turn each boot to aid in removing the boot from the plug. I would get a new upper intake gasket and consider replacing the wires at this time also. There are actually only 3 spark plug wires, so for what is involved to get to them, I would replace them. I have found alot of the wires will arc to the upper intake manifold.
Hi
The misfire could be being caused by a number of things, such as:
1. Worn/dirty spark plug - Clean/replace spark plug/s
2. Spark plug lead breaking down - Replace spark plug lead
3. Or possibly the intake gasket. If the intake gasket is leaking it causes a vacuum leak. with this vacuum leak at idle it will cause a misfire. - To check this, take a can of carb cleaner (or WD-40 may also work) and when the car is running, spray it along the intake by cylinder number If you see/hear the engine change then you have a leaking intake gasket.
Trust this helps
Alan
You will need a 12 mm wrench and socket, a 10 mm socket , an extension and the socket for your spark plugs, and an intake plenum gasket. Start by pulling the positive cable from your battery. Next pull the intake cover off the top of the motor. On the drivers side you will see 3 coil packs or "cops" ( coil on plugs) those have two 10mm bolts, one on each side. Remove those , pull the coil, unscrew your spark plug with your socket, and replace.
On huge passenger side you will have to remove the upper intake arch (plenum) to get to the remaining three plugs. Repeat process from the drivers side. !!!!replace your intake gasket when you remove the upper plenum or you will have a vacuum leak.
yes, the valve cover gasket is the only thing that can cause this, and yes, you have to remove the cover and put a new gasket in to fix. Please let me know if you have more questions.
you have to remove the upper intake to replace the back plugs.there is a bolt that goes throgh a bracket in front of the engine just above the power steering pump.Remove air intake hose ,accellarator cable, unplug sensors, and vacuum hoses. Lift intake trying not to damage gasket, Remove plug wires one at a from valve cover. use long extension and plug socket.I would replace plug wires also.Leave comment.
This is All you need for this Repair, ALSO Be Sure ALL GASKET SURFACES ARE VERY CLEAN. This Engine Requires MORE than MOST ALL Engines do for this Repair.
REMOVAL
To remove a valve rocker arm cover from the RH cylinder head, disconnect PCV closure tube from oil fill stand pipe at rocker cover.
Remove the Thermactor bypass valve and air supply hoses as necessary to provide clearance.
Disconnect the spark plug wires from the spark plugs using Spark Plug Wire Remover T74P-6666-A or equivalent. Do not pull on wire. Remove the wires and bracket assembly from the rocker arm cover attaching stud and position the wires out of the way. ALSO MARK THEM AS TO WHERE THEY CAME FROM !!!
Remove upper intake manifold.
Remove attaching bolts and remove the cover.
INSTALLATION
Clean the valve rocker arm cover(s) and the cylinder head gasket surface(s). Position a new service valve rocker cover gasket.
Position the cover(s) on the cylinder head(s). The cover is tightened in two steps. Tighten the bolts to 14-18 N.m (10-13 lb-ft). Two minutes later, tighten the bolts to the same specification.
Install the crankcase ventilation tube in the RH cover.
Install upper intake manifold.
Install the spark plug wires and bracket assembly on the rocker arm cover attaching stud. Connect the spark plug wires. Install the air intake duct assembly.
Install the Thermactor bypass valve and air supply hoses (if required).
First off, you don't have to remove the WHOLE INTAKE MANIFOLD. If you look closely, you'll see that the intake manifold is a two piece setup(Upper Intake, Lower Intake).
You will need a new gasket after removing it. Don't be cheap either, get one that is reusable.
First, remove the air intake from the restrictive airbox, then remove the bolts from the center portion of the intake not from the heads!!!(This is not a Chevy so the car's parts made on this intake is for people like us to work on)
After removing the "Upper" intake and everything else including any hoses, you may successfully remove the intake and lay it aside and guess what, you can replace spark plugs.
Replacing the front three is a no brainer so I'm not getting into that LOL. NOW, I HIGHLY suggest to go ahead and spend the extra $20.00 or $30.00-$35.00 if you was performance gains and better/longer performance usage, and get you some plug wires too. You only want to do this once (For a long time).
Do not use any other spark plug but an NGK brand, NOt an AC Delco although they call for it too, I wouldn't go with them. These stout V8 killer motors produced were specifically made for high performance.
Thanks for using FixYa - a FixYa rating is appreciated for answering your FREE question.
×