MTL_4runner

You'd think that would be enough time to throw an injector CEL, but anything's possible.

gpcollen1

I suppose it is possible.

Was talking with a friend last night and he didnt think that the Cat would give me the rough idle - he said it would be more of a power loss, especially on the highway at higher RPMs, getting on and off and passing cars to start. I still intend on moving forward with troubleshooting this weekend.

Hopefully i can get to a compression test, vac test, change fuel filter just for friggin kicks, and fuel pressure test may be possible. Still trying to locate pressure testing kit without having to buy one.

MTL_4runner

I agree with your friend and that's why I said it's just something to check. Don't rule anything out until you've verified it's good.....I learned that lesson many times over as a mechanic. Start with the more obvious stuff though like compression test. Also get an OBD scanner if you can because it will help you see any pending codes and check things like timing, O2 sensors, etc.

gpcollen1

I appreciate the assistance Jamie! Trying to knock these things out little by little (while taking care of kids, wife and other duties) is always fun. Hopefully I will have some more data this weekend.


I ordered the Auterra but i do not know if it will get here in time. I usually use a buddies scan tool when I get a CEL. I'll see what Autozone can do for me.

George

Baloo

Going through this thread, now I am a little worried. I was going to do the Seafoam thru the manifold this weekend to my 01 with 120K on it. Reading some of this thread, I am not so sure now.

MTL_4runner

Just run some in the gastank a week ahead of when you're going to run it through the manifold. It's not a huge deal, just helps minimize any possible fouling issues from what I've experienced.

mkgarrison5

just run 2 cans on a full tank first and then do the pcv valve treatment.. i did it and my truck runs fine.

MTL_4runner

Yep.

mkgarrison5

and i thank you for that one MTL ... it does run smoother, my idle isnt much better but i can tell a difference and my gas mileage is rockin' now!

Baloo

I ran a can thru last week, with miles I put on that's about 2 or 3 tank fulls. I will run another tank with two cans and see how it goes. It's a all Tacoma weekend since I have to do suspension work as well.

MTL_4runner

You want to run the Seafoam fairly concentrated for the duration of the tank, so put at least 2 cans in (you can add as many as 4 on a full tank), then fill the tank with the highest grade of gas you can get (ie 91+ octane or better, make sure it's a brand name like Chevron, Shell, etc) and run it until it is as close to empty as you feel comfortable (ie do your best to get somewhere between 1/8 tank and E without running out of gas). Try and resist the urge to top off the tank during that time even if the price of premium goes back down to $1 per gallon.

After your done the first part, then you can be pretty safe about running the next can straight in the engine (via the PCV or some other vacuum hose that goes directly into the intake). Always remember to pour SLOWLY when your dumping it into the engine itself and then shut the engine off right after you finish adding the last drop. Leave it for at least between 1/2 to 1 full hour and then restart and take it for a drive on the highway.

You may not notice a huge difference if your engine was pretty clean to begin with but I'd bet you'll see a decent improvement in gas mileage after with an engine that was in need. It is also suggested to clean the MAF when doing this for maximum effect (use the red extension tubes with the aerosol can to get the cleaner right down to the wires, but DO NOT TOUCH THEM.....after shake as much out as you can and air dry). I've switched over to using brake cleaner to clean the MAF because it does a much better job than electrical contact cleaner (with electrical cleaner the wires look better, but with brake cleaner they really look like new). Just be sure to let it thoroughly dry before starting the engine and pull the negative battery terminal to reset the ECU to relearn the new MAF readings.

For you guys in Canada, it's available at any NAPA store for around $10 CDN per can.

gpcollen1

Well did not get as far this weekend as i had planned. Just got my hands on the necessary compression tester last night. Did get to do a vacuum check though and nothing was out of the ordinary. My Auterra OBD came in the mail yesterday so I did a live run on the way to work this AM. Just trying to read up and interpret the results.

AF sensor readings seem a bit erratic but I have not seen a graph of a live run before.

g

MTL_4runner

Sent you a PM.

Anyone else using an Auterra, I thought this link might be helpful too:
http://www.troublecodes.net/articles...r_Review.shtml

gpcollen1

Just trying this out to see if it posts well. It was part of the run on the highway.

gpcollen1

The rest of the highway to getting off the highway and to idle at work. The 3 peaks 9red) and valleys (blue) to the left are accelerations in passing a few cars.

MTL_4runner

Can you post a graph of just the truck warmed up and at idle?
Let it idle for a 2-3 minutes and then burp the throttle a few times.

The rear sensor is an O2 sensor so you can see it swings in voltage depending on the lean/rich condition present after the cat. The A/F sensor up front is clearly almost flatlined.....A/F sensors show output differently than regular O2 sensors (they should only swing when the exhaust goes way rich or way lean).

Ordinarily with (2) O2 sensors (before and after the cat) you'd see something like this:

MTL_4runner

Maybe you could do an oxygen test result screen for us as well.

Like this:

gpcollen1

This is at start up and through warm up - dont know if more detail at any point is better. The big changes to the far right are just after i left the driveway and started up the hill - i think.

gpcollen1

Yeah - i think i can hit it up at lunch and try an O2 test too. Just feeling my way around this tool right now. interpreting data - well that is another story.

MTL_4runner

You'll love the Auterra, it's a very powerful diagnostic tool when you really get into it more. It takes some getting used to because it does have so many features.....the other half is also being able to undertstand what you're looking at and what is considered "normal" for the system you're looking at. You might also try the "fuel economy" (in the Dyno menu) on the way home to see how you're doing in that respect. Also helps you see what is the ideal speed to travel at for best MPG numbers......helps on long trips!

From what I see so far I think both your front and rear sensors look ok.

Here's another good article on O2 and A/F sensors:
http://www.autoshop101.com/forms/h37.pdf