Bought a 1995 Grand Am and replaced the cylinder head, spark plugs, coil pack, etc. Spark is good and plugs are top of the line. Machined and put together the cylinder head myself (that's what I do for a living). Car starts fine but idles rough. There is NO miss. Will drive normal but shakes and runs rough when idling, but runs like a champ when you drive. Please help me.
Sound very much like you have an air leak problem and even a seal problem to on the intake manifold and injector seals may be leaking same happend to me on my car and i found i had to strip it all again to sort it out .
the injector seals if they are not sitting right or just a slight spec of dirt there you have a problem.
air leaks to see if you do have one use wd40 can spray on the manifold and if the engine picks up you have a leak ok
i hope this helps
let me know how you go on thanks
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was it running this way before you changed the plugs? just a shot in the dark here possibly a defective spark plug, rare but not impossible. if it was running fine before changing them. Other wise I would take it to autozone and pull codes if it is P0350 #5 misfire we would use the process fuel, fire and compression. is there any engine coolant around any cylinders? Have you checked the coil packs? could be a bad coil pack. if no evidence of fluid around them proceeded to check for spark, fuel then compression. post back results or new post with more deductions. iis it no spark no fuel or bad compression.
There are individual coil packs for each cylinder. They are held in place by a single 10mm nut. Remove the nut and lift the coil pack up. You may have to wiggle it around a bit and pull hard. The spark plug is located in the hole you just removed the coil pack from. The spark plug boot is attached to the coil pack.
I would perform a compression test on all cylinders if you've already changed your plugs and wires. This willtell u if u have ay mechanical problems with the engine. Also even tho you've changed your spark plugs and wires did you check your injectors or coil packs to ensure they're good. A problem with either will also cause misfires.
The Spark Plugs are located under the Coil Pack in the Cylinder Head. You need to remove the silver cover on the front part of the engine which are held down by Allen Bolts to access the Coil Pack. You will need to remove the two bolts holding the Coil Pack to the Cylinder Head. Pull up on the Coil to remove the Coil and inside the hole will be the Spark Plug. The rear part of the engine next to the firewall has no cover so you will need to just remove the Coil Pack. The Nissan Maxima is very picky about the brand of Spark Plugs you replace them with, You should only use NGK Platinum Plugs or Better in your Maxima, Any other brand will make your car run rough.
TO REPLACE SPARK PLUGS YOU REMOVE COIL PACK MOUNTING BOLTS THEN REMOVE THE COIL PACK WITH BOOT OVER THE SPARK PLUG.YOU HAVE 6 INDIVIDUAL COIL PACK TO EACH CYLINDER. YOU NEED A 3/8 RATCHET WRENCH - LONG 3/8 EXTENSION -SPARK PLUG SOCKET - SPARK PLUG GAUGE.AND TORQUE WRENCH.THE 2000 MODEL JEEPS FUEL FILTER INSIDE THE TANK.1993 - 1996 MODEL JEEPS FUEL FILTER LOCATED LEFT SIDE OF THE VECHICLE NEAR THE FUEL TANK.
The intake gaskets leaking would cause the engine to have a misfire. Get a can of Brake Clean and spray in around the intake manifold on the top of the engine while the engine is running. The engine idle will go up or down if there is a leak. Also try swapping the spark plug with another spark plug to see if the misfire moves to another cylinder. If it moves then you have a bad spark plug. I hope this helps.