Still frustrated

[Typrus]

Well, after a month or so period of being parked (thought the fuel pump failed.. it just fell off its support and bounced off the rubber connector hose... grumble)
I started going again.
Fuel pump is strong. Pressure regulator works fine. I'm about 3PSI higher on both specs (idle with regulator connected, idle with regulator off)

Yet still I just get 25-26mpg. Power is still inconsistant. Some days I'll have plenty of it, some days it feels just meh for power.

What the heck next? The ignition system has been gone through (good plugs, good wires, cap, rotor, etc) the fuel filter has been done twice, I've run 3 cans of 44K and several of SeaFoam through her, I've SF'ed the intake... I'm getting annoyed here.

I had had a plugged primary cat. I hollowed her out and it did make a bit of a difference. I did the non-fouler mod to the O2 sensor, and I still throw a code.
Could the code-throwing have something to do with this? First issues with a partially plugged cat, now no cat maybe causing problems?

I've looked at getting a header for it and a better secondary cat and relocating the secondary o2 sensor behind it, but I dunno if that'll help either.


I'm really getting peeved that when I talk to 1MZ-FE automatic owners, they are consistently telling me they get 28-35mpg.... And here I sit with the 5-speed tutu getting less power AND less economy. Something isn't right in that picture.


HELP!

I hooked up a fuel pressure tester via a long long hose line to a compression tester thingy attached to the non-foulers and on a fully-warmed-up romp to redline through 1st 2nd and 3rd, I saw only spikes (on a very bouncy reading) up to about 3-4PSI. I know its not a proper exhaust backpressure gauge, but I don't want to pay someone to do an easy task.

[uibalnme]

How much have you already spent trying to work out this problem? How much MORE are you willing to spend to keep trying to fix it yourself? Now, imagine if you had just taken it to a professional in the first place.

[new echo owner]

What is your fuel pressure reading with the hose on and with the hose off? What code are you still getting? And can you direct me to where I can find this non-fouler mod, I am not familiar with it?

N.E.O.

[Typrus]

I really hate having to re-type after it times out... I should know better than to not copy the bloody message.

ANYWAY...
All the ignition gooies were done because when I bought the car it looked like everything was original and I wanted to remedy that. I only mention it to prevent being asked if I did my ignition stuff.

I do most of my own work, and am not a moron. I will not pay someone to do what I can do. Period. And I am willing to spend time looking things up that I don't know, talking to pros who are willing to take the time, and go about it in a logical way.
How much extra money would be spent trying to get a pro to figure it out? Hundreds of dollar that I don't have. I haven't done anything blindly or without reason. I don't throw money at problems if I can avoid it.
The 2nd fuel filter was done to make sure I didn't have a bad load of gas that loaded up the new filter. The cat was hollowed only after taking it off and seeing that a 9005 halogen bulb had a hard time shining through the media. The non-fouler was done to try and shut up the computer, being sans cat.
http://www.s2ki.com/forums/index.php?showtopic=229959
Just one of many walkthroughs.

I think it was code 12 if I remember right. Oxygen sensor deal. Catalyst efficiency low I believe.
Both Ox sensors are about 5000 miles old.

ALLDATA specs-
Key on, B+ and FP jumped on diag port- 38-44PSI
Engine idling with FPR vacuum disconnected-38-44PSI
Engine idling with FPR vacuum connected- 31-37PSI

Readings taken from a MAC pressure tester at fuel filter banjo as per recommended procedure (only I didn't use a second banjo, I substituted the original banjo bolt with a banjo bolt that was equipped with a pressure fitting, as supplied in the MAC kit)

B+ and FP jumped- 48PSI
Idle, vac off- 48PSI
Idle, vac on- 40PSI

[new echo owner]

To commend about your first commend about the time out, I just open a second tab for the thread, if it times out, I just log back in using the first tab, so I don't have to retype.

You must have an OBDI vehicle with a two digit code, and I just recheck, code 12 is for the knock sensor. If the knock sensor is having problem it could have retard the timing, which in turn would affect your mileage and performance.

The fuel pressure reading you have is slightly higher but still OK, it could also be cause by fuel gauge variance. Check it with another gauge if you want to be sure. Also check the MAP operation, one of the sensor that provides fuel enrichment under acceleration besides the TPS.

BTW, the post cat O2 sensor is mainly for emission purpose, it doesn't affect the performance of the vehicle. It is used to monitor the efficiency of the cat.

N.E.O.

[Typrus]

Code 21.. My bad.. Must have a lysdexic memory. lol
How might one check the MAP?

Hmmm.. I had thought that as well, but was told that it might try to enrichen or lean out the mix to get a better reading at the 2nd Ox.

Hmmm... Never did check the TPS. I'll go grab my ohmmeter and do some reading... Good resistance check is easy enough.

[new echo owner]

How did you read the code? Not that I doubt your ability, however, I would suggest double checking the code.

Did you test the O2 sensor to make sure that it is outputting properly?

N.E.O.

[Typrus]

E1 and TE1, count the blinks.

Maybe it was 27.. Dangit I don't remember. I stopped pulling it after the 4th or 5th time of it being the same thing and that was months ago. I'll go recheck. Also printed off the various sensor test procedures. Bundling up and grabbing my voltmeter here in a sec.

About to go check the TPS, IAT, ECT, Primary Ox and Secondary Ox, and MAP.

I'll try to remember to write them down and report back.

[new echo owner]

If it is code 12, knock sensor code, then the symptoms that you are having actually fits the condition of a knock sensor would cause. An O2 sensor would cause poor fuel mileage, but don't usually cause power lost.

N.E.O.

[Typrus]

Ok. So. Here's my findings thus far from this morning.

Reading at MAP sensor plug- 5.00 Volts. Perfect reading coming from the ECM. Now I need to find it so I can test the MAP under pressure and vacuum.

It was a cold night last night, maybe 32 degrees or so. Ambient is 50 right now.
ECT reading- 4.38 in 20K Ohm scale
The single-connector sensor right next to it- 1.78 in 20k scale

IAT reading- 3.35 in 20k scale. Ran it under warm water (easy to take out) and it went to 1.10 then gradually climbed back to about 2. Didn't run it under it for very long BTW.

Still need to fire it up and see if the ECT and one next to it gradually decrease resistance. I don't even know where the single-prong one goes. Likely to the gauge and the ECT controls the computer, yes? Then a third sensor to switch the fan? Thought I saw one in the rad anyway.


Now here's the fun one-

TPS.
VTA-E2 @ 0 clearance- .586kOhm (spec 0.2-5.7)
IDL-E2 @ .5mm- .4 or something like that (spec 2.3kOhm or less)
IDL-E2 @ .7mm- infinity (spec infinity)
VTA-E2@ WOT- 1.129 (Spec 2.0-10.2)

If measuring at VTA-E2, it will gradually climb from .586 to about 1.4 then actually start to fall back.
This would explain why a lot of the time 2/3 throttle is no less impressive than WOT? Yes? However sometimes it works flawlessly.

Dying TPS perhaps? Could that be kicking my butt?


EDIT!
Took it off the car and tested again and it worked flawlessly. Reinstalled it, and it worked flawlessly.... I hate that.


MAP is working great. 3.13V ambient, 1.6V at idle, and within range at all vacuum specs. Course I have to go reassemble my glovebox now... lol

[Typrus]

Its code 27.
And my ECT and gauge sender are working just fine.
Haven't had a chance to check the Ox yet.

[new echo owner]

What is the exact year and set up of your car? I know it is a Gen 3 and OBDI, and 5 speed, what else have you done to your car?

N.E.O.

[Typrus]

Aside from what is listed, AFAIK its stock. But the guy I got it from was a crooked jerk so I have no idea really. He claimed it was a JDM motor and that the original had been blown, but in pulling it to change the clutch, everything looked like it hadn't been touched... Ever. So who to believe? I dunno.
5SFE?

I run full synthetic oil with Molybdenum DiSulphide additives.

What else is there to say...

[new echo owner]

Well, if you are unsure about the engine, you may have to start from the basics, and work to establish where you are at, that's all. Did you ever do a compression test and leak down the engine? They are give you some idea on where the engine is health wise.

Code 27 is for the sub O2 sensor, which doesn't really come into play as far as power and mileage is concern.

What you said about the TPS is interesting, and indeed could have been the cause of your occasional power lost; however, I am not sure about its effect on fuel mileage. What you should do is measure the inputs at the ECU, this way you will also find out if the harness is good or not. Have you check the voltage of the TPS?

BTW, you said your glove box need to be reassemble, does it mean that is where you are measuring them?

N.E.O.

[Typrus]

I was just checking as per the FSM. It requires you probe the connector to test the MAP sensor. Didn't specify for the TPS or anything else.

When we did the clutch we redid the pan gasket too. Looked up inside, and aside from a Penz-yellow wax film on some things, it looked great. Cylinder walls shiny and such. But I'm thinking I will bust out my compression gauge to be sure. I will be beyond peeved if the engine is internally buggered. For a Yota, at 147k, It should just barely be devirginated with good oils and fluid upkeep...