fuel system

[4runner1992]

I have a 92 4runner with a 22re engine that seems to have a fuel system problem. At lest that what I think is the cause of the power loss. The problem first occurred when I was on the road and was accelerating up to freeway speeds. I shifted up to 4th and all of a sudden the rpms spiked up to just over 4k as it was trying to accelerate and then dropped back down to where it normally would be while doing that. At first I thought it was the cultch but its only doing it at hire rpm then I thought it was the transmission its self but have ruled that out as of right now because it if only occasionally happening not every time I drive. After this started to happen I was having some problems at low rpm or even just at idle. The engine felt like it wasn

 

[the_dingman]

Have you checked the O2 sensor and mass airflow sensor?

 

[4runner1992]

I have looked at the mass airflow sensor. I found that it is difficult to actually get at and it seems to be different then what ive been able to find information on. If what I think is the maf is the box on top of the air filter. I took that off a wile ago and sprayed every thing I could see down with electronics cleaner spray. The maf sensor ive seen in the past are 2 elements suspended in the middle of the airflow. All that ive seen in the maf for on my 4runner is just a little plastic looking thing with a little hole in it. Am I missing something in it? I did however try detaching the plug off the unit just to realize that it isn

 

[4runner1992]

Well I have now replaced the O2 sensor and the problem persists. Although it dose now fell a but more powerful and responsive. I then decided to take a look at the air sensor. Upon looking in to it I found that my engine doesn

 

[MT4runner]

Well as far as the Mass airflow meter goes, your right its not like most other vehicals. the kind where its suspended in midair measures how much its cooled down, the more air the cooler the sensor will get. in your 22re its a airflow meter, it measures how far the flap is open to know how much air your engine is getting.

The oxygen sensor, did you buy a nice quality one or a cheap one off of ebay? cheap O2 sensors can fail fairly quickly. Look into like Bosch or Aisian if you bought a cheap one.

and i would recomend not opening up your MAM.

 

[4runner1992]

i put in a DENSO O2 sensor in it. i had thought that that fixed one half of the problems i was having witch was the engine trying to die on me after i start it and try to drive (ushely at low rpm happens mostly when in paring or leavening a parking space.) but that started up agen today after driving around all day. still having the problem where it feel like slipping and it revs up high also. this one has rely got my confused.

 

[4runner1992]

update

just an update on whats been going on with my problem. i have finely after a few months of parking it. that the air flow meatier is bad. this kind of sucks but at lest i now know. so i have not yet replaced the AFM and wanted to know if anyone knew any tricks on how to fix it. its already bad so i cant nilly mess it up any more but if i can fix it without spending another $300 i figure it would be worth a try.

 

[fishrod]

Ha! I did the same thing, someone incorrectly told me that my 94 4runner had a MAF so I tried to pull it apart and spray it with cleaner, only it doesnt really come apart!?!?!

As far as I can tell (judging from the Haynes book) you cant really fix an AFM, you can test them using an ohmmeter but if they are busted its better off replacing the whole unit.

I wasnt aware that they are 300 bucks though! I was thinking more along the lines of $50-100 but I havnt tested mine yet as Im not convinced its the cause of my surging/choking issue when not properly warmed up.