and then there is my miss (please help)

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wymjym

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I’ll try to make this as short a note as possible.
I have a 97 SHO with 85K miles. I bought it from a fellow who miss led me quite a bit. I therefore do not feel as though I have any accurate history of the car.
I think the mileage is accurate. The engine did have a cam failure and it has been repaired and the cams welded. I have driven the car @ 3000 miles since adjusting the valves. There was the ‘TYPICAL’ coil miss. I performed all easy procedures to try to eliminate the problem. Then some more expensive ones, O2 sensors, maf replacement, super-duper $$$ spark plugs, etc. Still no joy, I checked the compression and the #1 bank had higher compression than #2 bank, by @ 15psi. All the cyclinders were winthin this range 165~180 (on my gage).
I swapped coils, no joy…so I finally bought 8 new coils and installed them. I checked the plugs before installing them and nothing looked obvious…some were darker and some lighter but non were white or black or really wet. Two of them were a little damp looking however. I installed the new coils, crossed my fingers and the car runs better, it idles smoother but…it still has a slight miss. I suspect that either an injector is partially clogged, the fuel system pressure is low or…I may have gotten a bad coil. The reason I think theere mught be a bad coil is that while they all came in Airteck boxes with the same part number, one of them had a different boot design and doesn’t fit very well into the spark plug valley)
The weird coil in in #4 so off comes the intake just to check that one out again.
I want to add that the wiring looks okay, not to say that there isn't a contact issue but the miss is sooooooo coil like (sometimes it idles just fine but if the AC is on it is apparent that there is a slight misfire and sometimes almost a dead miss. It always goes away as soon as the throttle it touched,
Any and all advice would be greatly appreciated as I would love to have this thing running properly.
I also ran three bottles of red line fuel system cleaner through it, new filter installed afterwards.
wj
 
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SHO#7

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If the miss clears up as soon as you hit the throttle even just a little, I would suspect vaccum leak. Have you shot around the intake with some starting fluid.

Mike
 

wymjym

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I had tried wd40 just hoping for any change in sound (no change apparant)...will try some propane tomorrow.
If I need to pull the injectors how difficult a job is that? If one of the cams is in one tooth off...how would that affect things?
wj
 

wymjym

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okay....I went out and warmed the engine up. I opened up a can of propane..no change in idle. I disconnected the fp regulator and it changed the engine sound but I still have the miss. I guess I'll be pulling the intake etc off this weekend and study each spark plug/coil/coil co0nnection/ etc.
Any other advise (other than to cross my fingers)
wj
 

me6894

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did you try it around not only the intake gasket area and TB gasket area, but also the vaccuum lines?
 
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