my ngk spark plugs in order from left-to-right, 1-5.. #6 missing... i noticed #3 looked liked it wasnt getting much of a spark compared to the rest. looks fairly new still. the last two pics is #1 and #3 at different angles. my 4runner is very sluggish so thats why i pulled the plugs. could it be a clogged #3 fuel injector?...

 

No boom boom for that one

 

#3 almost certainly clogged injector (could be bad connection or bad injector).

#4 looks a bit rusty - how's your coolant? If its rusty, I wonder about the head gasket. It's too bad you don't have that #6 plug. You may want to check the compression.

 

sb5 thanks for the response,.. i put these plugs on about two months ago. then about a month ago i did a compression check and cylinders 2 and 4 were leaking with coolant in the way. so i did a complete head gasket rebuild with the heads machined and valve job. i did however put back the spark plugs since they were still new at the time. cant remember the last time i serviced the fuel injectors, all i did to it was put new o-rings on them. compression is very good all across. #6 plug looked okay just broke in half as i was pulling it out so thats why its not in the pic. sounds very good at idle. it doesnt run rough or shaky at all... more like a throbbing/sluggish feel as im holding the pedal at a steady speed. yeah im thinking its a clogged injector?

 

also the #4 plug could be the result of what happened when coolant got to it the first time.

 

Check to see if there's an obvious problem with the connector, check the resistance on the injector. If those both check out, maybe buying a remanned injector would be the easiest - Beck/Arnley is $30 on rockauto

http://www.rockauto.com/catalog/x,ca...,parttype,6224

Or send 'em all to witchhunter.

Or buy a remanned set:

http://cgi.ebay.com/ebaymotors/ws/eB...m=280448595642

 

i'm not sure, but here is a good spark plug link;
http://www.autohausaz.com/html/spark...lug-wires.html

 

i would throw in a new fuel filter and new injectors all the way around so there is no doubt in your mind...

 

thanks.. connector and resistance all good... im probably gonna do that and order some from ebay and replace them all and then send my old ones to get serviced.

 

fuel filter, fuel, pump, fpr, and cor are all new

 

well take your old ones to get serviced and then store them in your glove box, along with a set of injector o-rings in case you run it to a jam down the road.. (nothinng like fixxing a problem on the road with cars whipping by at 70 mph )