I just replaced the plugs on my 1995 toyota pickup 5 speed. I checked the timing and it seemed to be slightly advanced ~about 14degrees before TDC. I adjusted it to spec ~10 BTDC and it seemed to idle very low. I jumped the T1 and E1 terminals like the manual said to do. Im wondering where i should go next :Cleaning the mass air flow sensor, adjusting the TPS to spec or adjusting the air bleed screw on the throttle body? Truck high idles when its cold and drops idle as it warms up like it should, but currently its low idling around 400 rpm. I believe the only code on the ECU are for the O2 sensors(as the previous owner told me). Other than that, the truck seems to run fine. Any suggestions would be great. Thanks

 

How'd it idle before you changed the plugs?

 

Adjust the idle air screw to spec. 800 +/- 50

 

it was idling the same way before i changed the plugs. I noticed alittle rpm change when adjusting the timing(closer to spec i was, the lower the rpm went even with the terminals jumped). I didnt want to adjust the idle screw yet if there were other things preventing it from idling correctly.

 

It's normal to have to adjust the idle screw after setting the timing, then recheck the timing and again the idle adjustment. Don't get too picky unless it's way off, back and forth twice is probably enough.

 

The same problem on a 93' 4Runner. Among about 50 different thing that could be causing it, there is the possibility that the TPS is bad altogether. I just finished up with my nieces 4Runner today with a new TPS and so far so good. Just picked one up from Autozone for $75... and get this... its sold as a Duralast part but its a Denso OEM!!! Check out the pix...

Also you can see the old one is definitely bad after i opened it up. The contact brushes were a bit outta wack and there is definitely wearing on the contact of the resistor. This of course was done after I did the factory Ohm check and it failed.

No joke I've had her truck and my house about 10 times since they bought it a year ago fixing one thing after another.

 

There are several things that can contribute to the same symptoms. Believe me I've replaced too many parts on these damn 3vze's not to know... let me know and I can help

 

Yep, same here! It was a nice surprise, especially having the cheap one I got off Ebay live to the ripe, old age of 3 days.

Don't worry about the screw, just adjust it. I do so much work on my engine and MFI system I have to do it every couple of weeks. You can't hurt it. Shoot for 800 RPMs when warm, you might have to run it for 5-10 min before you can get an accurate reading, otherwise you'll be adjusting it again after a longer trip.

 

I'll start with the TPS and go from there. Truck is parked 2 hours from school due to a wiring issue. Went out sunday night to drive back to school and i didnt have any gauge lights or tail lights. All other lights worked. All fuses were good, but i was fixing my speaker wires this weekend behind the radio(Aftermarket), and i reconnected a white with green wire(as it looked like it had broken/been cut). After starting my truck i smelled burning wires and sure enough it was one of the wires behind the radio. Just need some time this weekend to check over it. I'll pick up some throttle body cleaner and mass air flow cleaner as it couldnt hurt the idle issue. Thanks again for everyone's responses so far!

 

You don't have a "MAF" to clean.. The AFM on this is an air vane "Volume air flow meter". Google should turn up a good explaination of the difference.