'Refurbishing an 87 runner. Got it on the road. I could use some input from our distinguished WIZARDS.
My MPG is 17. The engine has a slight"groan", specially when accelerating. The pickup is somewhat lackluster. I notice black deposit at the tailpipe. Yesterday I replaced the O2, and the air filter. Also, the idle is intermittently high and low. When restarted from warm, it will start then die, unless I tap the pedal a couple times. Is this enuff info for some hints, what sensors to check, etc? Thanks in advance!!

Ah, a new project! <img src="/forums/images/graemlins/smile.gif" alt="" />

http://www.4x4wire.com/toyota/maintenance/30_V6/throttle_body/ Would be my first stop. The article is for a V6, but the idea is the same.

Am thinking the groan is just your MAF doing its thing.

Make sure the TPS is set correctly (www.4Crawler.com 's website) Pull the plugs and check their appearance.

That's for starters anyway.

Our 4runner 22re is also running very rich, and it across all the cylinders, is it possible the injectors are staying stuck open? We are getting an Oxygen circiut code from the ECU and have looked for vacuum leaks, verified timing, adjusted valves, replaced air filter,wires and the plugs. Which are still wet with excess fuel. If the fuel pressure regulator failed would this keep the injectors from closing once open?
Any ideas would be appreciated.

Make sure engine vacuum is getting to the FPR. If not then pressure goes to maximum at all times and this causes rich running at idle and part throttle. I bypassed all the extra stuff on my 22RE and ran a vacuum line straight from the intake to the FPR.

From this:


To this:

my truck did the same thing when a i put a cone air filter on it.......yea that lasted 5 minutes i put my k&n drop in back in and it still did the same i pulled the EFI fuse for 10 minutes and started it up. still the same thing but once i drove a for 5 miles everything was back to normal. it could be a misadjusted tps also. when mine was out of spec you can here the air coming thru the mass air flow

"I bypassed all the extra stuff on my 22RE and ran a vacuum line straight from the intake to the FPR."

Thanks 4crawler!
but.... what does the vacuum solenoid do that is upstream of the fuel pres reg? In my Haynes, it mentions that the system turns it up and down depending on speed. ?? you did not notice any difference when you removed it?

Anyhow, my TPS was always thinking the throttle was open, never closed, so I adjusted that, and tightend the clamps better on the MAF hose. We'll see next time I drive it.

As I understand it, the VSV before the FPR is there to boost fuel pressure to prevent a possible vapor-lock-like condtion. The idea is the VSV vents the FPR to atmosphere when hot starting, boosting the fuel pressure to the maximum. Then the rest of the time, the VSV is closed, passing intake vacuum to the FPR, letting it adjust fuel pressure normally. Interestingly, it is only used on 4WD/22REs, the 2WDs and cars don't use it.

As it works:

Low vacuum = high engine load = high fuel pressure = high fuel flow.

High vacuum = low engine load = low fuel pressure = low fuel flow.

I've run w/o the VSV for 3-4 years now, never noticed any starting issues nor any running issues, hot, cold or otherwise. Just cleans up the valve cover, lose 1 pair of wires, 1 VSV and one vacuum line.

Once again, 4Crawler, you are a credit to this board. Info you have provided covers same condition concern on my truck.

Thanks,