The 3VZE engine used in about 60% of the 1988-95 Toyota 4-Runners and pickups.The 3VZE had the following problems:
1)headgasket issues
2)idler bearings (for timing belt) tend to seize
3)bad fuel economy,sluggish in city and highway
4)engine bay full with engine and parts so difficult to work in and around engine
5)valves/lifters need special tools to adjust and a bit difficult
6)engine not as reliable as 22R-E
7)ordinary replacement parts or modified performance parts are not as common as the 22R-E
First see if headgasket was replaced under the recall (Toyota calls it "service campaign or adjusment"),you can get full maintenance from any Toyota dealership for free provided the present owner signs a privacy disclosure agreement (Privacy Act of Canada).If headgasket wasn't replaced see links at bottom of this thread.
Check back fenders and frame for deep rust by taking a hammer tapping the back frame, do a fluid analysis on engine oil by buying a fluid/oil analysis kit from any Caterpillar dealer's parts dept or some heavy duty shops this test will tell you how healthy the engine is, if the engine oil and radiator coolant was changed regularly on those engines you can get at least 300 000 miles.
Remove the spark plugs look at them as a picture means a thousand words if it has a manual tranny park the vehicle on a hill facing downwards put the tranny in first gear and shut it off, don't use parking brake or foot break if the vehicle holds itself well in first your engines piston rings are great conclusion you have high compression (no leakage past the rings),also while engine is running remove oil filler cap and see if you have blow by, a healthy engine should have a vacuum effect when palm of your hand is placed on oil filler cap.
Finally if you have a portable air compressor perform a leak down test on the engine, for more info Google it.
By the way find out where the guy works which would tell you if it has highway miles or city miles.Pull the ECU codes.
Here are some good starters if you buy it:
1)Check all 6 spark plugs,rotor & distributor cap
2)Clean throttle body
3)Replace front (exhaust/front pipe)oxygen sensor
4)Replace alternator carbon brushes
5)Replace starter copper contacts
6)Lube brake bleeder screws,other parts including rubber suspension parts & spare tire assembly
7)Check 5 speed manual tranny pilot shift lever bushing & seat for excesssive wear and in auto tranny CHANGE THE FLUID to avoid shift solenoids from going bad
8)Sandblast frame specially back frames if you live in an area where it snows and road salt is used then coat frame with
http://www.por15.com
And in detail below are the above info:
Check all 6 spark plugs,rotor & distributor cap.Then clean the throttle body and replace the oxygen sensor.Also pull the ECU codes incase a part is an electronic sensor is faulty or bad wiring.
Usually excessive short trip city miles combined with low octane gasoline causes excessive carbon build up in the throttle body which does not allow sufficient airflow and hence the butterfly flap/accelerator plate to close all the way.
To clean the throttle body remove the air intake hose, examine the intake and throttle body for excessive carbon build if found then buy a can of throttle body cleaner labeled "safe on oxygen sensors,TPS's and catalytic converters" do not use carb cleaner make sure your engine is fully warmed up prior to using as when the throttle body is hot it dissolves the carbon easily and quickly.
The labels usually specify to park the vehicle at ground level (0 degrees,no inclination) and have the engine running but I disagree I instead park the vehicle on a hill facing down then shut the engine off, hold a rag below the lip of the throttle body poor the stuff and use a tooth brush.
22 Toyota head gasket & oil sludge recall sites:
http://www.toyotanation.com/forum/showthread.php?t=216122
http://www.brian894x4.com/V6headgasketrecall.html
http://www.off-road.com/toyota/4runner/topqs.html
http://www.yotatech.com/~corey/4runner_faq.htm
http://www.alldata.com/recall/make/Toyota_Truck.html
http://www.alldata.com/TSB/60/94601650.html
http://www.yotarepair.com/Campaigns.html (3.4L,V6,headgasket recall)
http://home.off-road.com/~bibelheimer/3.4v6_headgasket.html (3.4L,V6,headgasket recall)
http://home.4x4wire.com/erik/t100/3.4v6_headgasket.htm
http://www.yotatech.com/f116/special-service-campaign-90-95-4runners-89-95-trucks-93-98-t100s-66901/
http://www.jasperengines.com/pdf/5SFECoolantLeaksTB.pdf
http://www.nordicgroup.us/oil.htm#Toyota Sludge
http://www.toyota.com/about/news/product/2002/04/03-1-consumer.html
http://www.usatoday.com/money/autos/2002/04/04/toyota-sludge.htm
http://www.petitiononline.com/TMC2003/petition.html
http://groups.msn.com/ToyotaOwnersUniteforResolution/headgaskettsb.msnw
http://groups.msn.com/ToyotaOwnersUniteforResolution/headgaskets.msnw
http://www.babcox.com/editorial/ic/ic100052.htm
http://www.autosite.com/content/own/service/index.cfm/action/recalls
http://www.msnbc.msn.com/id/9241475/
Sidney