SurlyJohn

So my 92 4runner with the V-6 3.slow was running decent for a 3.0 for a few months. When I bought it I replaced the cap, rotor, wires, spark plugs, fuel filter, O2 sensor, K & N air filter, and did the ISR mod.
I used good NGK parts, Iridium spark plugs even, and the O2 sensor was a NGK direct replacement also. I also replaced the MAF sensor since it had some issues with a clean wrecking yard one from a 1995 model with the same engine.
It ran well for a couple of months, now for no reason at idle usually the check engine light will come on. It does Idle rougher when this happens like it is going into limp mode. The idle isn't all that smooth normally, but gets rougher with the check engine light on.
I usually am driving when this happens, and before I get to work, it will almost always turn back off. Also, the big other thing is that it's a pig on gas even more as this has been going on, whether the check engine light is on or not.
So long story short, any ideas about the intermittent check engine light? I haven't pulled the codes since it never seems to happen when I'm around home. I will do that next time I'm driving it on my days off.
I really just want some decent mileage since this thing is getting about 200-250 miles per tank right now. Any ideas or things to move on too would really be appreciated.
I'm going to take it to a shop for driveability probably since I'm about at the end of my knowledge.

Targetnut

You need to pull the codes. It should store the codes even though the light went off.

Really anything else is just speculation.

n4ynu1010

Yeah jump the diagnostic connections and turn on the key and see if it has stored any codes and go from there .

Jay351

also what brand parts did you use?

SurlyJohn

I went on Sparkplugs.com and dropped about $200 on everything, which was very good pricing for all the parts I replaced. I used a Toyota brand fuel filter, NGK Iridium spark plugs, NGK wires, NGK Oxygen Sensor, and cap and rotor were Denso's. K & N Air Filter for the stock air box. The VAF meter I replaced was off a 1995 Limited with the 3.0 V-6, which I understand are interchangeable. Bought some Denso oil filters and wiper blades too while I was on there.
I will pull those codes on Tuesday since it's my next day off. What jumpers do I have to bridge to get the codes? I know you guys say this all the time, but it's my first time pulling codes from this 4runner. I have a code scanner for my VW's, you just plug it in to OBDII.

Jay351

TE1 and E1 with a paper clip, turn the key to the "run" position and count the blinks that the chech engine light gives. A constant blinking without any change means there are no codes.

n4ynu1010

Yeah TE1 and E1 , pop the top on the little gray box (1X1 1/2") next to the much larger black box with the fuses/relays in it on the passenger side fender well , here is a link with instructions and a decent little pic of the connector under the hood (at least this applies to 87/89-93/94 years with some variations) :
http://www.off-road.com/toyota/tech/codes/