Had a blast at TDS this past weekend, made the long drive from Oregon and back without much of a problem - except for the fact that my 4Runner died twice at freeway speeds on the way home. I just recently replaced the fuel filter, and never go under a quarter tank of gas. I ran it down to the empty mark once or twice on the drive, so I'm wondering if I clogged the filter with rust and crud. The truck would buck for a fraction of a second at an inconsistent rate. It might've done it for a good ten seconds then not do it for the next 15 minutes. Then it would completely sputter out, like it was running on two cylinders, and die when I coasted to a stop. It would start right up, albeit sputtering, and revving it to redline would clear the stutter out. Now, I'm gonna replace the fuel filter, but how do you all get rid of the rust and crap in the tank? Is there anything else I should be looking for? Wires are good, cap and rotor just replaced too...

I know somebody out there musta cleaned out their gas tank before - anyone? Bueller? <img src="/forums/images/graemlins/smile.gif" alt="" />

shoot! Guess I forgot to hit SEND.

In short:
Yeah, all that bouncing around 4wheelin' fun probably stirred up the sediment in the tank.
Hopefully the filter is just plugged. Symtoms persist? flip up the back seats and tada, access panel for the fuel pump. Pull that puppy out and check it out. Sock OK? Rust in the pump? get a new pump maybe.

After that, drop the tank and clean it. first, try to take it to a radiator shop to be hot tanked. Less cost, WAY more work and HUGE MESS = DIY cleaning. We're talking harsh acid and a biological product called "Marine Clean."
after you get the goo, varish, and rust out of the tank, try coating the inside with tank sealer. Careful, cheap stuff or bad prep and the stuff peals or flakes off which plugs up the sock on the fuel pump. Best stuff is the POR product.

http://www.ratwell.com/technical/FuelTankRestoration.html

has a GREAT write-up on how to do it.
Why do I know this stuff? I have an MR2 that sat for 3 years with fuel in it. Sludged the tank which plugged the fuel pump. HAVE TO drop the tank to fix. <img src="/forums/images/graemlins/frown.gif" alt="" />

good luck and "Acid to water, that's how you aughter."
-Leinies

Your description sounds more like a water problem to me than a muck problem. You can drain the tank nicely by simply removing the drain plug on the bottom. There's no baffles in the tank, so it easily flushes with water. Remove the pump from the tank and you can get your arm in there to use a sponge. Basic soap and water will do the job just fine.

It's a very easy, low tech job to do.

That's the nice thing about it being a Runner instead of a truck; the rear pax access panel. Just be careful of your wiring, so you're not sayin' bad words! IIRC, the drain plug is a 17mm.

Thanks everyone, guess there's a couple of ways I can handle this. I'll tear into it this weekend. <img src="/forums/images/graemlins/cheers.gif" alt="" />

Okay folks, tore into the fuel tank today and found that everything was clean. We changed out the fuel filter anyways, and the motor still has the variable hesitation and stutter <img src="/forums/images/graemlins/angry.gif" alt="" />. Any other ideas? My CB antennae is next to the radio antennae on the passenger side - think that might have fried the ECU? Maybe coil/igniter gone bad? Would a bad fuel pump cause such symptoms?

I'll start by saying that your antenna line should NEVER be routed close to your ECU; the EMI from your coax when you key the mic makes it go batschidt. This note is also in the FSM. Science in action!

Have you tried pulling codes yet? The ECU can store them, and not necessarily flag your check engine light. Check that first.

Might also check your 02 sensor harness to make sure it's okay.
When's the last time it was changed, or a thorough tuneup done for that matter?

Couple other things; has the t'body been cleaned lately (see the maintenance article here; for a V6, but same idea)
TPS behaving/set up correctly?
Spark plug wires-- how old? That would also point you to the coil/ignitor
Distributor cap/rotor

You say variable stutter; if the EGR valve was carboned up, that usually is around 2400 rpm or so.

Anyone else?

Teeff!!!! <img src="/forums/images/graemlins/cheers.gif" alt="" /> If I ain't careful, might get an EFI system down; thanks for the reminder on pressure. <img src="/forums/images/graemlins/smile.gif" alt="" /> Am still rewiring Blackie, but she's under 2 feet of snow right now.