i can understand being a newbie and all that this type of thing doesnt get much attention. thats ok, heres a pic of my daily driver runner in progress. <IMG SRC="smilies/flipoff.gif" border="0"> <IMG SRC="smilies/laughing.gif" border="0"> <IMG SRC="smilies/thefinger.gif" border="0">
I had the same high rpm misfire problem with my old Jeep(which I got rid of a long time ago in favor of a new Toy). Try this "home remedy". In the dark, with the engine running, spray a little window cleaner on the distributor cap and along the wires(with the sprayer on mist, not spray). If the wires are bad, you will see sparks jumping through the mist.
thanks for the reply guys!! i thought it was the cheap new set of plug wires so i bought some $50 8mm decent ones. helped alittle for a while. New fuel filter, new k&n aire filter, new tps, new injector o-rings and seals, all new intake gaskets. Only thing i keep thinkin is the oxygen sensor. I hear both sides, no it wont make a difference, and yes that will fix it. I hate throwing more money at it cause its getting replaced with the ford 5.0 this winter. I like the spray water trick, i'll try that tonite. Oh ya, i ohmed out my coil and it was out of specs by 10 ohms. enough to make a difference? thanks everyone!!
just a tiny bit to tight, would that make it miss? i keep mine at 7 and 11 instead of 8 and 12. also this is a head off of an 82 maybe? i dont know, but i know it didnt have fuel injection. i had to do a few little mods to get it to fit, like shaving a 1/4" off!!! it was on the shorter block motor. thanks for any more ideas.
Go buy GENUINE TOYOTA plugs, wires, cap, and rotor.
I know two toyota technicians who work at different dealerships and don't know each other, so this ain't just two buddies workin down at the auto dealer. From what I hear this is farily common among Toyota (And japanese mechanics in general):
They'll use autozone coolant, fluids, whatever. But when it comes to the engine components, NOT ONE of them will use aftermarket equipment. I found this out the hard way after I went out and got 'performance' plug wires, bosch plugs, and autozone cap & rotor when I hydro-locked my enging. Lo and behold, I had a miss at idle and then at 4k+ RPM.
Guess what? It went away as soon as the toyota stuff got put on. There's a reason that Toyota stuff costs more than the 'performance' aftermarket. I'm not saying that this WILL cure your problem - if it's mechanical and not electrical, then it doesn't matter what plug wires you use, but it's somewhere to start, and it happened to me, and that fixed it...</font>
I pretty much agree with Masteryota. As far as plugs go they don't have to be Toyota though. Toyota does't even make their own plugs (think they use NGK's). If you get new plugs, stick with NGK's, or Bosch. Whether or not you want platinum plugs is up to you. Most definatly stick with toyota distributer and spark plug wires as Masteryota explained above.
My best inexperienced and uneducated guess <IMG SRC="smilies/tongue.gif" border="0"> would be the ignition coil. The ohm spec. is on the ragged edge of what I would condemn. Check for arcing/tacking (black lines) around the coil and igniter too <IMG SRC="smilies/biggrin.gif" border="0">
Thanks for all the ideas guys, i'll try a new cap and rotor from the dealer. wires to i guess. i always trusted beck arnley parts but i also know about the dealer quality (t-stats). Ive always thought is was a good mechanic but this one has got me. I'll keep ya'll posted. have a good weekend all.
just one more opinion... be sure the plug gap is set at fact. spec (.032 I believe). Definatley go with the factory ignition components as the guys said above.
The only thing I can think of is the air flow meter - if the contacts are dirty, the motor will surge or miss slightly at a steady cruise rpm. The AFM is serviciable by removing the cover and "carefully" cleaning the contacts with electrical parts cleaner and a swab (be sure to not leave residue or cotton material behind) - then just re-seal the cover w/ silicone.
A lazy O2 sensor can contribute to a miss as well, but will typically trip a code if the sensor is bad - have you checked for a stored code?
Just my $.02 - hope it helps, good luck!! These little problems can be very frustrating, but let us know what cures the problem!
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