Interesting defiantly interested to see what you come up with.

 

I wonder if i can just unplug the knock sensor and drive it to see if that's the problem...

I'm going to check the FSM tonight to see how to test the knock sensor.

 

fill it with premium and see if it still dose it.

 

I have done that. It runs a.little better, but not much.

I don't think it's pinging. I have certainly never heard it.

Last night i looked at the FSM. It says the knock sensor is.a.piezo.electric transducer and it looks for a specific frequency to determine knock.

I am going to try unplugging it to see what happens. It might throw it into limp home mode.

It will probably. Be the weekend before i can mess with it.

 

Well for starts, the 3.4 puts out like 190hp brand new, you're saying its not exciting? What do you expect?

Second, the power drops off as it shifts up? ... yep ...

Third, timing retards as load increases... yep...

Buying a 400 dollar scan tool for nothing... priceless...

 

Awesome.

 

New information.

It's supposed to rain today so i drove the truck to work. I ran the scanner while i commuted.

It seems that it's going into open loop every time i get on the throttle.

Hmmm...

 

Look I know I am kind of a jerk, but none the less what I'm telling you is that this all sounds 100 percent normal. Yes Including the open loop when you mash the gas. On another note, that looks like a pretty cool little scan tool.

 

If your looking for more power without SC the sucker, maybe I can suggest something i'm doing for my 01 V6 quite soon. Granted I do work at Jet , but I don't get a penny from sales, as retail it cost $400 for this upgrade, but through amazon you can get it about $140 off. I have an intake (deckplate mod w/ K&N) and cat back exhaust w/flow master muffler and a throttle body spacer. i'm going to the dyno soon, with just the intake/exhaust see what numbers it get. then have my engineers upgrade the program in the ecu, then dyno the truck again. it will work with a completely stock vehicle if yours is still a stocker.

http://www.amazon.com/Jet-65002-Com...Computer-Upgrade-Package/dp/B0018CUELY/ref=sr_1_1?ie=UTF8&qid=1334956243&sr=8-1

 

I'm not looking for power. I just want it to run like it's supposed to.

 

Jet is still around? Wow, would rather go urd so its user tuneable!

 

46+ years and counting. Been here for about 4 months ago. Story is company started with Carb's only back in the day, and now been doing EFI for bout 20+ years. No knock on URD but it's twice the price for the same thing, outside of the adaptability to further upgrades i don't see much difference. Ours, you just do your mods, then the ecu upgrade would be the last part to get. Personally, I think it sucks we only sell programers for fords/chevys but i guess im the only import fan that works here .

 

X2 open loop at Wide Open Throttle

unplugging the knock circuit will get you limp mode, killing any timing advance

How "new" are the spark plugs ?

A little Seafoam to clear any carbon buildup..

The ECU on the 4 runners and D cabs seem to hold back on advance mapping.

disconnect the battery and then start driving it like ya stole it while it relearns. it helps a little.


Other than a little free flowing exhaust, my truck seems more robust than any other 3.4 ( I drive it hard ) 4:56 gears on 35's muds, and it still chirps the BFG's

 

The #1 problem with the non~CARB 3.4's is there is No EGR Valve..

Combustion temperatures and NOx are controlled by engine timing.

to replace the EGR function, the timing it tuned down, to the point it lacks the uuuummmmph without the high timing curve.

 

hahaha, I like you. enjoy chasing fairies.

 

Frank, did you ever figure out what is causing the timing retard? My truck has been doing this off and on lately. Sometimes I stomp the padal and the power is there, sometimes not. I can see the difference in advance on my scangauge. What the hell's going on? Is a sensor dying and the engine is trying to protect itself?

 

I don't see any way to tell if the knock sensor is backing off the timing, at least with the scanner I'm using. I can tell it's retarding, but there's no way to know if the knock sensor is activating.

I tried dumping some cleaners in the gas to maybe loosen up the carbon in the motor and maybe clean up the injectors a little.

After that, I'll try reading it again to see if there's any difference in timing at WFO.

But the weather has been nice and the trucks been sitting in the driveway. The motorcycle gets 40 MPG and makes me smile.

I'll get to it.

And I'll post up what I find when I do.

 

OK, This is interesting.

I had put some Gumout in the tank, and about a week ago I poured a bottle of Yamaha Ring Free carbon Remover in there on top of it.

Then, when that burned down to a half tank I poured in a bottle of Lucas Deep Clean injector cleaner in there.

It's juiced pretty good right now with solvents and I have been running around doing errands.

So I pluged in the scanner and hit the entrance ramp to the freeway. Wide open, between 4 and 5 on the tach.

It's showing 16 and 18 degrees advance at full throttle. Pulling better too, as you might imagine. Six or eight degrees more than the ten it was running before is a substantial difference in power.

So is it cleaner combustion chambers and less knock for less timing reduction, or is it cleaner injectors and better atomization for the same result?

HMMMM...

 

Also-

Before, I was seeing fuel trim percentages moving around between positive six to positive nine.

Now, I'm seeing negative three to positive three.

This has me thinking that the injectors were cloggy and the ECU was increasing duration to compensate.

The problem with this thinking is that I'm not sure that I was observing those numbers under the same conditions. If not, it means nothing.

I'm about 75 percent sure those numbers are from a steady cruise at freeway speed.

I find it interesting regardless.

 

most of the cleaners are just higher octane gas IIRC. i try and sea foam once a year or every other year depending on how many miles i drive. and after every oil change, run about a 1/3 of a tank of 91 and drive the truck hard to clean her out. been helping my trucks last for a long time, my :2cents:.