AnthonyVB

After i went wheelin which happen to involve lots of water everywhere, ive been getting a hesitation and a miss fire under acceleration and load. under idle its fine and in neutral runs fine only when it requires more fuel. ive replaced plug wires and fuel filter. Ive done my research and i know it could be the Throttle position sensor, or the Mass airfow sensor, or the fuel pump or fuel pump relays.i dont want to dig into all of these without knowing for sure. There is no range of rpm that it occurs its anytime its under load, meaning the EGR is working which i made sure of. Im frustrated angry and desperate please any advice is welcome -Anthony.

ToyotaViejo

Repairs require digging in the form of diagnostics.

You don't have a Mass Airflow Sensor; but rather a Vane Air Flow Meter. Do they break or wear out? Yes. Does it happen often? Not really.

Relays generally work or don't. I've seen a few "lazy" relays that either undervolt or take a while to switch over, but that doesn't sound like your problem.

Knocking on wood, these fuel pumps tend to run forever, unless you're the type that never has more than 3/8 of a tankful.

A fuel pressure test would rule that out pretty quickly. Bad news: Toyota uses about the strangest fitting on the test port, so unless you already have a good gauge and adapters that fit, it's almost definitely going to be cheaper to take it to a shop and have them test it than to buy the gauge and fittings.

Assuming that doesn't come back bad (if it did, you're out a pump and filter and dropping the tank), next culprit is the TPS. That's where my money is. They're flaky parts in bad, hot locations and control much of the vehicle's mixture and advance.

Don't even bother trying to do anything except the DMM tests with it in-vehicle. Best thing to do to replace it is to remove the whole throttle body, and follow the instructions (both for testing and for replacement).

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

The factory service manual has diagnostic procedures that usually require little more than a screwdriver and a DMM for nearly every electrical subsystem. Grab some coffee, the manual (google it) and a DMM and go.

Terrys87

iTrader: (1)

Did you dry the rotor cap out? I seen you replaced plug wires. I dont know the 3.0 but if you run into a fuel pump issue. I suggest getting one from here. They cost about $150 at a parts store and $300 at Toyota. These have worked great for me. Look identical. Also just for information, dont go much below a 1/4 tank. Link>>> http://www.ebay.com/itm/New-Fuel-Pum...item35b6422050

ToyotaViejo

Eh, shoot. The other thing I left out was the ignition coil and igniter. Those + water = bad. Manual has test procedures for those too.

AnthonyVB

Thank you all so much I will try those and hopefully get back to you tomorrow

ToyotaViejo

Just found this forum about the Factory Service Manual. I don't advocate intellectual property theft, but these manuals are 20 or more years old and of basically no commercial appeal to anyone outside of the handful of us still driving these old buckets.

Toyota would score a lot of points in my book making the FSMs freely available after the model hits 10 years. I've been told that in eastern Asia and African markets, the LandCruisers are all sold WITH the FSM; and you can even buy a Toyota tool kit that has everything needed for repairs. Selah.

http://daemon4x4.org/portal/downloads.php?dcid=17

AnthonyVB

Whatre the consequences or not running the TPS ive got it unplugged and it seems to be running smoother but i want to make sure that thats the issue, by running it for a few days to make sure it doesnt reoccur.

ToyotaViejo

You'll probably notice reduced power, especially at highway speeds. Your fuel economy will probably go down to 10-or-so MPG as well.

After some time driving it around, you might well get a check-engine light. You won't hurt anything in a brief span of time, though.

Over longer spans of time, you'll wear out your catalytic converter and O2 sensor from running extra rich. Probably foul plugs too - and you will never pass even the most lenient emissions test.

ToyotaViejo

The best way to feel a little more confident in the TPS diagnosis is to test the resistances per the 4crawler page listed above.

AnthonyVB

I unplugged the TPS and drove it for a few days, and it ran fine only while warming up and under quick/heavy throttle it missed and some random occasions it still hessitated just not as much when i have the tps connected, it idled 10x better without the tps, but i plugged the tps back in and now im getting a hesitation lie i did before, im wondering about a fuel pump now. - sincerely still frustrated pissed and annoyed

ToyotaViejo

What you're describing sounds *exactly* like the TPS is the problem.

Have you done the resistance tests on the terminals of the TPS as described here?

Without the TPS, it will bog at wide-open throttle, since the computer has no way of knowing that it's at WOT. It will also run craptastically at idle, because the computer has no way of knowing you're at idle.

I wouldn't go dropping the tank just yet - at least until you've DMM'ed the TPS.

You said it yourself - the truck ran better with the TPS disconnected.

AnthonyVB

Well it definitely the tps tried plugins it back in and the thing one run barely under acceleration, can I fix this one or am I going to have to invest in the 91$ one?

AnthonyVB

The VTA-E2 reading that I got when I tested it today and its suppose 200-800 ohms and ir read as 1 or infinite but the other connections seemed to check out I'm not sure what this means I've read through that manual and it doesn't tell me.