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Showing results for tags 'spark plugs'.
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Hi CZC! Long time lurker and first time poster. I have much enjoyed the content that is provided here on CZC forums. I am in a pickle however. Long story short. My 280z was placed in the garage for nearly a year. I am trying to get her running smoothly. When I crank the car, the car will run roughly (as if some cylinders were not firing.) My car would shake all over the place. A friend told me that it was mis firing so I did the easiest and most common things first and that was to replace the spark plugs, spark wires, cap and rotor. After installing all the said things, it ran and idled under 1000 rpms after gassing the car for maybe 5 mins (still rough shaking...). Now, here is the weird part. I turned off my car in attempt to screw the battery on tightly (i left it loose). I approached the battery with my wrench and sparks flew from the positive terminal. Boy... did I have to change my underwear... I detached the battery cables and then reconnected them in positive then negative fashion. The car will now only crank....It wont start. My friend assumed that I short circuited a fuse when I made the battery spark but I couldnt tell where to start. Any suggestions as to how to approach this dilemma? Best, Jalapeno Business -
Hello all, I'm having a frustrating problem and I wanted to get some opinions. I've searched quite a bit but haven't found anything that either I haven't tried or was relevant. That back story: I have a built 3.1L stroker (not done on the cheap) with E31 head running somewhere north of 11:1 compression. The most runs well with good compression across all cylinders. The head has had a sigfnificant amount of work done. Another piece of infromation is that it has a timesert in sparkplug hole number 3 due to an issue with the head that predates me. I'm running triple webers and Electromotive HPX ignition. I AM running PCV, as using advice from Tony D I created a vacuum log with a restrictor on one end for the PCV valve (mounted to a grommet which is mounted where the pipe once was all pressure fit). So I THINK I'm exacuating pressure from the crankcase. I have no other leaks that I know of. Engine mileage is 1200. Onto the issue: Symptom #1: On cylinder number 3, I have a small amount of oil coming out of the spark plug hole while the engine runs. As I drive, it slowly works it's way down the side of the block and makes a mess of things. Symptom #2: When the engine starts after sitting for more than a few hours, I get a greyish smoke while I idle. Once I drive off into the sunset, the smoke dies off and doesn't reappear until the car has been off for several hours. Things I have checked: Valve Cover Gasket - it doesn't leak and the oil clearly originates from the spark plug hole. Spark Plug Torque: It's well torqued, but even it if it wasn't, you would expect something other than oil to escape. Valve Seals - I replaced them last night and the problem persists. Ignition - the plug is firing correctly, so I wouldn't think it's unspent fuel coming out. I'm not running overly rich either, 12.5 at idle. 13ish -.13.8 at WOT on the idle/progression circuits and 13.0ish on the main circuit. And now on to what's left for my theories: Head cracked - Lord, I hope not. Oil passage nicked - Along the above lines, do the oil passages run anywhere close to the spark plug holes that a timesert may have affected. Oil passage nicked - I assume there is way too much metal in the combustion chamber that the machine shop doing the head work could have gotten close to oil passages? Bad oil control rings - If I had a bad oil control ring, would I not be BURNING oil consistently rather than for a few moments at startup (aka like when you have bad valve stem seals)? Also, would it be possible for oil to find it's way all the way up the cylinder wall and out a spark plug hole? Bad head gasket - I have an HKS 1mm head gasket on now. The problem existed with an HKS 2mm head gasket as well. Using ARP studs torqued to spec. Of all those, I would prefer one of the last two to be the case even though I don't relish pulling the engine anytime soon. The oil comes out clean with no antifreeze or anything else in it when drained. The antifreeze looks good. Thanks, Brett -
I don't really know where to start, so please bare with me. About three months ago, I sent my carburetors off to Ztherapy to re manufacture them because the rear three cylinders quit firing, and my float bowl was overflowing. I finally got them back (2 months later), installed them, did all the necessary tuning that I could without the car running (including float level), and it will only fire up if I've got both carbs fully choked. It'll run at high rpms until I unchoke it, and then it just sputters out. Turns out, (from the front) the 4th, 5th, and 6th cylinders are for sure not firing, and I think the 1st isn't because its exhaust channel on the exhaust header is the same temp as 4, 5, and 6. When I pull 4, 5, and 6 spark plugs, the tips are drenched in oil, but they're still sparking. Could it be that my cylinders are full of oil, and it's not sparking? I adjusted the timing, distributor gap, and valve clearance properly about 800 miles before I had to send off the carbs, so I don't think it's any of those. I just don't get why those cylinders aren't firing. Please feel free to bombard me with questions and help me figure this out!