dtjone

I have a 1993 4runner with the six cylinder 3 liter engine
For about a year I have been trying to fix a problem with engine power.
It started out with the engine not wanting to rev to high rpms when on the interstate and progressively got worse to the point where it is now.
I have difficulty getting the rpms above 3,000 when driving
With the vehicle in neutral I have no problem revving the engine up to the redline.
I have taken the car to two mechanics, neither was able to fix the problem.
I have checked for any sort of Head Gasket issues, there does not seem to be any sort of problem there.
Compression is good.
Engine smokes a little when starting. (it will let a little puff of white smoke out from under the hood the first or second time I try to crank it)
After that it usually starts and there is no smoke.
Anyone who might have any knowledge of what might be the problem feel free to comment

fourwd1

Your cat conv could be clogged.

__________________
- - as seen in FOUR WHEELER magazine July 06 and OFF-ROAD magazine Feb 07 - -

84 4Runner - ARBed 5.29s F&R, 4.7 & 2.28 t-cases, Chevys, AP x-over, BudBuilt x-member, 2" drv trn lift, 36" TSLs, 30 spline Longs

80 something p/u - Buick 231 V6/TH-350 trans, Holley 4 bbl, Weiand intake, dual batts, dual tanks ...

89 4Runner - stock

OzzyO

Try having your Mass Air Flow Sensor Checked.
I was having the same problem only more severe and it was that Sensor.
BTW I have a 94 4runner V6.

Good Luck
OzzyO

chachy6959

I would check the MAF. Mine went south and acted like yours. I bought a used one from a junk yard for 80 bucks and worked great. A new one will run you at least 500 from O'Reilly's and the dealer wants seven. Basically it is an auto choke. Take off the air filter and see if the flapper moves when you rev it up in gear. If it works when you move the flapper then that is the problem.

You may have a clogged fuel filter also. I have crud in my tank and it effects the beast when the fuel level get low.

Might even be a vacuum leak but that is a far shot. But a lot of my vacuum hoses were cracked when I got my truck and it ran much better after I replace most of them.

Let us know the problem if you find out.