jsrusse11

my 93 all of a sudden has no power. when i step on the gas it just bogs down and takes a very long time for the rpms to rise. idles very rough and back fires when i step on the gas. already checked distributor, put in new plugs, new plug wires, tried to clean the throttle body but could need to be taken apart its still kind of dirty inside. thought mabye a vaccum leak but haven't been able to find one. any ideas.

green91runner

have you tried replacing the fuel filter? (mounted on the frame rail) lots of posts/threads how to do it. pretty easy job and cheap... even if it doesn't fix your problem it's wise to change it (unless changed recently)

Denk

That sounds dangerously like the AFM. Check to make sure that connection is good. DO NOT remove the connector tho. That will fubar it permanently.

I had a similar problem. Coming down from wheelin' and all of a sudden the engine quits. Try to restart and it goes...but when I try to give it some gas, it peters out. Turns out that the connection to the AFM was at fault. Later I had to replace the damn thing. Good Luck.

jsrusse11

replaced the fuel filter today. no change. also tested the AFM and it showed up as 279 ohms and its supposed to be between 200 and 600 ohms.

green91runner

seems like the afm is ok.. another possible (albeit costly) would be a faulty o2 sensor.. can really mess up the ecu...

i pulled this link off google, dunno how accurate it is.. and it isn't specific to toyota's, but might give you an idea. sorry i can't be of more help.
http://www.users.bigpond.com/jack_st..._repair_1.html

frankenrunner

did you recently change the oil or top off???

i ask because an excessive amount of oil, due to an improper dip stick reading because of unlevel parking surface or unreleased vacuum prior to reading, can cause everything to "bog" down.

dusty98

I saw you checked the distributor, have you checked your timing? It almost sounds like your timing belt slipped.

Bigblock

or a burnt valve. does it backfire through the intake or the exhaust?

91 4Runner

Plugged cat... Mine was doing the same thing 2 days ago - new cat fixed...

jsrusse11

got a computer reading and it said its running lean. checked the oil and it seems fine. when it backfire its though the exhaust. this problem happened all of a sudden so is that possible to be the cat then?

Bigblock

Mine did this also,it turned out to be a burnt exhaust valve.do a compression test,then pull the valve covers and see if any of your valve clearances are way too tight.As in 0 or less,so to speak.

jsrusse11

i'm starting to think timing belt now. replaced it like 3 years ago though. is this possible?

91 4Runner

Plugged cat....

Ganoid

That rules out converters and exhaust valves... Both would cause a rich condition. I personally would start by checking the fuel pressure. Then move on to other things that make sense.

So let me get this straight... Your converter plugged while you where driving down the road in an almost instant fashon????

Cats dont plug instantly or even over night.
Oil level?? heh Im not even gonna touch that one.
C'mon guys where do you get this stuff??? Hell yes its made to be removed thats why its a plug!

jsrusse11

how do i check the fuel pressure

Bumpin' Yota

HELL YES that's possible!!

Do your timing belt now, I got 10 bux that says your belt stretched and skipped a tooth... They say you should change at 90k miles, I change at 60k - 70k just to be safe...

I unplug my VAFM ALL the time with NO ill effects. Even if the ignition is on, albeit it throws a code if the vafm is unpluged, it still works fine. VAFMs ARE robust if nothing else!

frankenrunner

i'm seconding "Bumpin' Yota" as i now know that it has been 3+/- years on th e "T-belt". a very likely cause for a "backfire" & power loss.

gwhayduke

Forget the years...3 years probably won't deteriorate the rubber on the T-belt. How many miles on it in those 3 years? Probably less than 60,000. It's unlikely the belt stretched and slipped with so few miles. Which brings us back to the other possibilities, of which plugged cat is pretty plausible. A new cat from MagnaFlow is only about $50 on Ebay and only $55 here locally.

AgRunner06

If he has a problem with his cat it might be bright orange when running.