sc4runner23

Ive read that tons of people have had problems with there cylinders misfiring. Im wondering what the best idea is to fix it. Ive cleaned the MAF sensor and when i do that it runs fine but after about a day after i clean it, it goes back to running crappy. Should i buy a new MAF sensor. Ive read so many different things it could be, im almost wondering if its just worth it taking it to toyota.

hross14

Search--search--search--we have covered this alot lately--Cool?

4runnerFireman

sc4runner23.......DON'T replace the MAF sensor right off the bat......start with plugs (Denso)....then wires (NGK or stock yota wires).....if that does not help, it's probably an injector like mine was.....you can swap coil packs to see if the p0302 code moves to the new cylinder....still no luck? then swap the injector out to another cyl like you did with the coil pack....that is the cheapest way to help diagnose it without dumping a bunch of money!! good luck, keep us posted

sc4runner23

well i recently changed the spark plugs and spark wires. Do you think they arent gapped right could that cause the cylinder to misfire.

4runnerFireman

well if you get the plugs from the yota dealer (they can be hard to find otherwise), they should be denso and double pronged.....even though it calls for 40 thousanths gap, they are already gapped, so don't mess with em' anymore!! Based on what myself and everyone else on this site has been thru, i strongly doubt it's a plug. Search posts, I also posted a thread that will give you some insight...it makes my head spin just thinking about this issue anymore than I have to....search under my name...what part of SC are you in? I'm in Charleston

4runnerFireman

HERE, i'LL JUST COPY & PASTE IT FOR YOU....It's always co change the Plenum gasket too in case it's sucking air in through the side of the intake!!






Talking 4runner Cylinder Misfire/Miss
First of all, I wanna say thanks to the people who post good stuff and actually help people, you know who you are. And those who don't know how to put a socket onto a ratchet, please stop typing!!! Hopefully what I am about to say will help some of you, I know how frustrating this problem can be.

I had the infamous 4runner miss, scanner showed cylinder #5 misfire, but no other info. If the motor was cold, after sitting for a couple hours, or overnight, it ran fine. It was when you shut it down to run into the store or something, fired it back up, it would lope at idle up to about 300 rpm's. SOUND FAMILIAR? Of course it does!! I spent 2 months on forums, emailing and making phone calls, no one had DEFINITE answers. OK, so first, I changed the plugs & wires, didn't help. Then, I swapped the coil pack from cyl 5 to cyl 3, scanner still showed the misfire to be in cyl 5, so that rules out the coil pack. So, I kept researching since I didn't want to drop $100 or more for a fuel injector and it not be the problem. I spoke to the head mechanic at my local stealership, he said he deals with it all the time and that he would check it for $45....Sounds like a good deal right? NOT!!! He had my truck for 5 hours, then called me to tell me it was the coil pack, so then my foul language started. I already ruled out the coil pack, remember guys??!! He said 9 out of 10 times it's the coil pack, and that the injectors have a very low failure rate....Hmmmmm, yes I know that, but this guy does not understand my failure rate with luck!!! Luckily, he found it in his soul to search through his tool box....GUESS WHAT, he found a fuel injector!!! He gave it to me, told me to swap it out (I guess I could have swapped out the injectors like I did with the coil packs to see if it threw another code, but hindsight's always 20/20!!) and pay him what I thought it was worth if it solved the problem. He also stressed that I was pretty much wasting my time, since the injectors rarely fail. He said it was probably a burnt valve (EVEN THOUGH HE DIDN'T DO A COMPRESSION CHECK) ARRGGGHHHH........So, I went home and started pulling the motor apart, throttle cables, intake, vacuum lines, intake manifold, fuel rails etc. Swapped the injector out and put everything back together. Switched the ignition on for 10 secs to let the fuel pump prime the rail, turned the key and BAM......cranked up like it never missed a beat!!! BUT, not fixed for sure yet right? Right!! Let it idle for 10 mins, shut it down, started it back.....still running good. Drove it for a few miles, shut it down, started it back....still A ok!!! That was 3 days ago, driven 200 miles since with no problems....IT WAS THE FUEL INJECTOR!!! I hope this help some of you out there, feel free to ask me any questions and I will reply as soon as I get a chance!!

Moral Of The Story.....If I didn't do any testing/reading (or if I was a woman) before taking it to the yota shop, they would have charged me $300 or so for coil pack, diagnostic & labor....then the next time I shut the motor off and restarted it, I would have realized that it didn't fix the problem....That's how people get hurt, haha....have a good day and good luck!!!
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99' SR5 4x4, V6, AT, 110,000 miles, leather, sunroof, Yokohama Geolander A/T's, Clarion Max385vd 6.5" touchscreen DVD, Circa 1994 Phosgate Punch 60ix running Polk 10" sub, Kicker 75x4 running 4 Polk 6.5's (Alice in Chains cranked to 11!!)...12v power points Always hot

hross14

You dont have to use dual prong--a platinum or iridium will work just fine.

A word of advice here--learn to test the parts you are wanting to replace--alot of these issues are MILEAGE DEPENDANT!!.

Ohm your wires--(1 ohm per inch of wire)--unless you just want to change them--but all the other items can be sweeped/tested....with a voltage meter with an ohm setting.

All these miss fires lately should be consolidated into a misfire thread sticky