Engine Light throttle miss

Dontknowchit

Active Member
Jul 31, 2017
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I'm not sure, but I may have a very light throttle miss. I just dug through my ignition and pulled plugs, replaced wires, polished contacts on button and cap. The only thing that stood out was very light build up on a couple contacts in the cap lid. Looking at the plugs, they all looked good overall, but one looked just a little different. #8 was darker than all the others, still dry and no fouling. My AFR looks good.

The symptom is that at 4th or 5th gear cruise, very light throttle input, like 10% of less pressure. I can dedect a very subtle and inconsistent skip or miss, no sound. It's something that will get really annoying on a long trip on the hwy, but nothing at full throttle or idle. It's only at very light throttle input at cruise. Not constant. I was thinking a bad or fouled plug but not really other than #8. Could a fuel injector that only sprays at WoT or had poor atomization cause this. I already replaced wires for no reason so rather not throw more parts at it unnecessarily. Ive got a new fuel filter and new 255 pump in back. These are recent injectors.

Anything else to investigate other than an injector cleaning/check?
 

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I would say that you should probably be looking at that #8 injector. Move it to another cylinder and see what the plugs look like after some miles. If they have some miles on them and are fairly old then just send them out to get cleaned and be done with it.