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Discussion Starter #1
Had a issue pop up in the last week.

Ended up pulling 3 of 8 Brand new sparkplugs today to see if I could tell what was going on. These only have 40 min's or so of run time
Left to Right
Cyl 1 plug, Cyl 5 plug, and then Cyl 7 plug
Took out number 7 only to find that it looked as if I just took it out of the box... no gas smell to it. I'd say I have a fueling issue. I'll test spark to be certain but pretty sure something is going on with the BRAND NEW Injectors I have. I'll update as I learn more information
 

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Oh yeah if it looks that clean, something isn't going on!
 

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Reading Spark Plugs

The two black ones show those cylinders are being grossly over fueled and the clean one shows that injector isn't firing at all. I suggest pulling the remaining 5 out and see what they look like. As your CrossFire originally had a MAP sensor what does your HSR use? If you're still using a MAP sensor I'd suspect it's hose is disconnected or it's wires are un-plugged.
 

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Discussion Starter #4
Map Sensor has been swapped out twice, all the vac lines are new.

IMO its more of the injectors not working correctly. This set of injectors have only 40 min's on them, the previous set only had 14 min's on them. The vendor has been good about replacing them. This last set was flowtested prior to shipment. I need to prove, sort of speak that its the injectors first before anything else. But I do believe thats the source of the problem.
 

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the injectors may be fine
it may be the wires going to them that have issues
 

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Discussion Starter #6
the injectors may be fine
it may be the wires going to them that have issues
Thats something I'm considering as well. Tomorrow morning I'm gonna start troubleshooting and see what I come up with.
 

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Way Too Rich

I still think you have a problem with your MAP sensor because of the gross over fueling. If you have one of those hand vacuum pumps connect it to your MAP hose and pump up a full 29" of vacuum and see how your engine runs. Then let the vacuum out and see how it runs. There should be a HUGE difference. The MAP is the only thing I can think of that would cause your plugs to get that sooted. Or a bad ECM.
 

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Discussion Starter #11
Yep, I found the problem.
Tested Spark...perfect
Tested fuel injectors and harness....perfect

Compression test was 0, removed the valve cover gasket and immediatly saw my problem
Helps when you lock down the poly-loc




 

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yipes !
 

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Yikes!! Glad you found it.
 

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I had a set of those goddamned nuts and I threw them away. I prefer the stock self-locking nuts and always have because I've never seen one loosen up in the 45 years I've been twisting wrenches. But as you're running roller fulcrum rockers I guess you have no other choice. Just glad you found the problem in your garage rather than 500 miles from home. I guess you now know you make an adjustment then LOCK IT before moving on to the next one.
 

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glad you got it figured out Ed
 

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Glad you found the problem. Mine is still waiting for a transmission when I get finished with this semester.
 

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Discussion Starter #19
Glad you found the problem. Mine is still waiting for a transmission when I get finished with this semester.
that sucks! You doing the tranny yourself?
 

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I had a set of those goddamned nuts and I threw them away.
we used them for years w/o any issues in our old IMCA/NASCAR GRAND AM claimer motors and those would last 30-40 races before we pulled 'em apart.
We'd adjust the valves every 10-15 races depending how many 30 lappers and 50-100 lap races there were

Of course street use is different , you don't wanna pull things apart as often , if ever

I'm guessing it was an "oops" though , not a part failure
 
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