I have a 94 runner 3.0V6 manual. Getting bad gas millage so I replaced the O2 sensor, plugs, wires, cap/rotor. Car ran worse afterwards. Idle varied around 2k to 300 randomly. Thought it was a bad O2 sensor, replaced that with aonther from same online store (generic, maybe that is my problem) and no joy. Took it to get smogged, passed all but timing. Was off by about 16 degrees (had the belt replaced about 6 months ago, think the guy did a shoddy job aligning the cams) Lined up the timing from the distributor all the way to the bottom stop to get the timing to 10. Now the bastard stalls when coming to a stop, but idles fine while stopped. Severly lacks power on the freeway; 4th gear, 3200RPM and tops out at 60MPH (the clutch is fine) It jumps adn coughs when cold, and shakes a little all the time. No engine light......doesn't help much. Do these symptoms sound familiar to anyone else out there?? Vacuum leak? I know some of you guys on here really know your trucks, hoping you can help. Thanks- J

 

What brand of products did you use? Just curious, as sometimes cheapies are crap.

-For plugs use NGK or Denso
-For wires use either Toyota, or NGK
-For cap and rotor use Toyota
-Use Denso for o2 sensor
-Get your timing checked again to be sure its set fine, and it isn't slipping
-Go thru all vacuum lines to make sure they are there, make note of blank ends
-Check compression in all the cylinders
-Check your intake for holes and such, and replace your air filter
-Make sure that the plug wires are properly done, matching the rotor, wires, and cylinder


After you do all that you pretty much dud a full tune -up and it should run well after that.

I have a slight feeling that your wires and cap and rotor are ed up. My wires were bad and it caused my 3.0 to run like crap.

 

Thanks man. I'll check all of that. Start with a Denso O2 sensor and see if that helps. Curious, I thought wires were wires......why are some better than others? More/less resistance?

 

Yea the resistance and the core of the wire.