Plugs look pretty good.

Engine should idle cold around 1K, when warmed, that should drop to around 750 or so.

 

Did you drive it with the 02 removed and checked if the 8 and 5 misfire is gone? Either way, the IAC isn't going to give you a misfire. But can be the cause of the way high idle rpms. As can the TPS. The misfire is most likely bad cat, carboned vaves, cracked head. All of which are very common with an 8 and 5 misfire.

 

Have to take a break and go to my sons school orientation. Gonna pick up new IAC while I'm out then check it out. I'll try driving without o2 sensor this evening if I have time. if not will let wife drive it monday and see what happens. If the misfire comes back, then I'll drive it Tuesday (my day off) without o2 sensor. Don't think it's a cracked head, oil looks good, and not consuming any coolant, and no smoke out exhaust.

 

The heads have a habit of cracking at the valve seats , so it will have nothing to do with coolant. Not trying to bum you out. You previously stated "no money". Just trying to help with that factor . How do you know misfire on 8 and 5? Scanner?

 

This particular truck has the nice feature of being able to toggle ignition on/off like 3 times and then it will give you trouble codes on odometer display. threw codes P0305 and P0308 so I looked them up on the internet and came up with cylinder 5 and 8 misfire.

And yeah the no money thing sucks....selling my truck because I just got a job after a month of unemployment and its a 30 mile round trip drive.....about $120/week in fuel. need something more fuel efficient then I'll buy another truck when I get back on my feet.

 

Those 2 codes are not a cheap fix, so just sell it if you dont have the money. Take the loss and make it up with a vehicle that gets better MPG's.

 

Sorry, dbl post.

 

Well, Not sure what to make of it.....put in new IAC ran a bottle of Seafoam through intake via vacuum line off brake booster - drove truck 37 miles at 50mph plus most of the time. runs like a raped ape, idles a bit rough with needle hovering around 900 rpm but no CEL coming on. gonna pull o2 sensor tomorrow or tuesday and run it again and see if there is any change. Won't sell truck (wife won't part with it, she's REALLY attached to it) plus we've already got $1600 in trans rebuild, $1,000 in tires and $2300 in paint. At this point I'll save up for engine rebuild if that's what it comes down to. Plus I'm already selling my 99 if I have money left over I can use some of that to fix hers if need be.

 

As I stated in a previous post , carboned valves . Now run tons of Techron Plus in the gas tank through it for a couple months and you might get lucky.