eddieleephd

You said you tested it did you ever test it while operating it?? meaning did you slowly turn the throttle and watch what happened when you did??

Matt96Tacoma

I am ready to find a high cliff at this point!

Eddie.. I tested continuity on the lower pins. When idle (closed) it should have continuity and when open it should not. I tested and it had passed several times..

On the new install it sputters even more! I can not beleive it! I got a different FSM to look at and it says to use a feeler gauge .025 closed (Yes Continuity) and .029 You should NOT have continuity but I do?

Also a new code...

P0510 - Closed Throttle Postion Sensor --

P0120 - TPS / Pedal Sensor A Circuit Malfunction

I did have the Ignition OFF when installing the new TPS because I did not want to erase the codes. Is the new P0120 from me disconnecting the wiring harness? Not sure it would throw a code since the IGNITION was OFF

Thanks..

Matt96Tacoma

Can you do me a favor and post your FSM info on the Throttle Positioning Sensor.

What I have is page 195 of the 1634 version. I tried to post but too big (57k)
Greatly appreciated!!

Kragen should have the new TPS this afternoon...

When checking resisitence VERY SLOWLY, I do not see any gaps in the readings? It appears to be testing fine as before. I need to find out what the voltage is supposed to be and perhaps check that?

Tragic Drive

Matt96Tacoma

Thanks Tragic...

I will check the voltage right now!

Matt96Tacoma

Interesting about the Intake Air Control being OPEN or short? Is there a way I can test this? My FSM does not show any wiring diagram or info on this. I know where it is and what it looks like but nothing on diagnostics.

What manual is this? Maybe I can find it online and download?

Matt96Tacoma

The voltage was perfect at 5.0v

Tragic..Thanks again for taking the time to post the pics!

Tragic Drive

This is from the 96 4runner Factory service manual (FSM Pub# RM480U). I suspect that the 96 Taco to be the same or very close in regards to motor control.

You can find the manual at Toyota Tis

Matt96Tacoma

Thanks...

I will grab it and see what I can find...

eddieleephd

Unfortunatly at this moment I believe that what you need to do is check the ECM there is a section on it in the FSM Tragic may be able to post the ECM diagnostics for this... it may simply be that the parts that you installed and had before are working fine but there is a short in the line between them and the ECM the only way to check this is at the ECM... it is kinda a bastard if I remember you have an obstacle in your way an alarm?? but the best thing that you can do at this moment to specifically diagnose this is to trouble shoot at the ECM... a nice multi meter and or a volt meter will suffice.
probably shoulda recommended this before but obstacles.. stop throwing parts at it and do the diagnostics of the ECM and save a few dollars maybe...

Matt96Tacoma

Just installed the NEW TPS sensor and callibrated (.21) Closed - .29 (Open)

As soon as I started driving I got a sputter bet it went away and drivinng fine.

Can you do me a favor and post a picture of your Intake Air Temperature sensor with it plugged into the wiring harness. I want to see what side the voltage (yellow/green) wire is on.

Thanks..

Matt96Tacoma

Well here is the latest....

I was able to confirm the yellow/green wire is located on the left side with the release clip facing up. I drove the truck all day yesterday and still the intermittent sputter. The check engine light was still off and then it came back last night P0510 and P0120. I know that the new TPS cannot be bad? It is the second one now...

I went over my FSM again and read and confirmed that everything I have done has been correct. I then looked at the FSM from this site and noticed something different. I noticed that the one here mentiond using a vacuum pump to calibrate the TPS and mine doesn't? Strange...

I looked at everything again and noticed a HUGE MISTAKE on my end. I was measuring .22 (closed) and .29 (open) off the wrong screw. My book shows it point to the screw/nut that is under the other screws that are against the throttle lever. I measured and it was WAY OFF. I did not mess with those screws/nuts but changed back the lower ones. I then turned the TPS until I had the correct reading and calibrated using the top screws off the throttle lever and checked voltage/ohms. Everything was now corrected. I drove the truck for 30 minutes and no sputtering and the CEL turned off. I know this was an error on my end and I am positive this will fix the problem. Thanks for eveyones help...

Matt96Tacoma

Well... I am still dealing with the same problem

After calibrating the TPS correctly my code went away that I created in the first place. The old TPS was fine but I had removed and installed wrong. Anyways...the truck still sputters intermittently and this is what I have done recently...

I decided to purchase 2 new oxygen sensors (bosch) and installed. I still have the sputtering and now throwing a P0420 code. I think this is because the new 02 sensors are more sensative and are picking up the sputter and thinking the cat is low or clogged. I have called bosch and they said I can return/replace when I am ready. I figure it will be the rear sensor after the CAT if the sensor is actually bad which I doubt.

Since the sputter still continues I decided to say screw it and just install a new fuel pump. I figured this was the last piece to the puzzle and would resolve. I installed and still have the sputter!

I then retraced all my steps and decided to seafoam the motor and tank to possibly clean the injectors and remove all carbon. I used 2 cans in the tank and 1 in the intake off the brake booster hose. It smoked like a freight train for 10 minutes and then I drove for 2 1/2 hours and did not sputter. I figured I had fixed it with cleaning the injectors / motor and then after parking the truck for 3 hours I drove it and sure enough it started to sputter. I read up on Engine Coolant Sensors and decided to try that also and no luck.

The last thing I can think to check is the fuel pressure regulator? I pulled the vacuum hose off and NO GAS was in the line but whe I smelled the hose I can smell gas. I am assuming this is normal? I have decided to install a clear tubing to watch to gas the next time it sputters. This will be hard to determine since it will more than likely just run back into the regulator and down into the return fuel line. I will have to rent another fuel pressure regulator to test with the vacuum line connected and also removed. I could not connect it to the fuel rail before due to my wiring harness and other parts in the way. The fitting on the rental is huge and I couldn't install on the rail. I will have to install to the rail to see if this is the problem. Going over my notes I see that the last fuel test was 65 pounds before the fuel rail/regulator. It should be 38-44 pounds on the rail. Once I can test this on the rail I guess it should increase 5-10 pounds when the vacuum hose is disconnected? If it doesn't change I guess the regulator is bad. Or it will be bad if the pressure is high?

Any thoughts...

Thanks for all the input

eddieleephd

in the future do all the tests first!!!

eddieleephd

CHECK YOUR TIMING MARKS!!! be sure they all line up perfectly!!!! this has recently contributed to this issue i another thread!!!

ricky

This sounds eerily similar to an issue I had with my truck a couple years ago. I replaced the fuel filter, had the deal do an injector clean, replaced spark plugs, and a few other random things. I replaced the plug wires and my problems were gone. Though the difference is that my sputter was more consistently there, and on occasion would go away. I figured out my problem after I washed the engine compartment and the sputter went away. Then I KNEW it had to be electrical.

Matt96Tacoma

I thought I would post a little update on this thread to let you all know that finally the truck is running GREAT!

After replacing part after part and still having the intermittent sputter with no check engine light I finally decided to take it back to the dealer again. The dealer did not charge me and said to wait until I get a check engine light and that perhaps it was the intake manifold. I gave him a printout of everything I had done and of course it seems to be a nightmare since I am not a Toyota tech. I had checked everything I had done about dozen times if not more and still the same results? I decided to replace the injectors thinking this must be it. The injectors were costly and guess what, still sputtered. I was pissed and decided to buy a MAF and see whats is what. The new MAF had same result and I was able to return luckily and said it was the wrong one. As my wife is seriously having doubts about the truck and starting to not want to drive it anymore I took it to a very well known mechanic in town. $500 dollars later in just tech time they gave it back and said that everything checked out fine and it only failed a few times and they were unable to figure it out. Pissed off about spending $500 and still nothing, I decided to just give up on this truck and accept that it will sputter forever. A couple months later I was in the auto parts store getting some wiper blades and saw this old man that looked like he had been working on cars his entire life. I asked him if I could pick his brain and he said sure. I explained everything that had happened and what I had done and he told me to keep it simple and only focus on the spark plugs and the wires. As I drove away I thought about how I had checked this already over and over and over. I removed the iridium plugs and put back the oem and it still misfired and no check engine. I then went back to napa and got new wires and again the same result. I then decided to take out the brand new distributor and return it also. I installed the new distributor and sure as sh%t the truck stopped sputtering! All this time and shops with all the expensive machines could figure this out? I guess the lesson here is just because it is brand new out of the box doesn’t mean it is working correctly. All in all I will never sell this truck for the rest of my life and will hand it down to the kids after everything I have gone through. I know it is a long story but I wanted to let everyone know the cause of the problem and also say thanks for all the help along the way! I also took a case of beer to the old man after finding out where he worked.
Matt

DownRiver

So are you saying? The Distributor was bad?

Sam hain

My truck has a bad misfire at 3000rpms, I changed out plugs, plug wires, TPS, crank shaft position sensor, MAF, igniter, coil, rotor button, distributor cap, and ECM and the truck still missed. Me and a buddy took the distributor cap off and I bumped the starter and he said he could see it arc inside the distributor. We swapped mine with a spare he had and miss was gone.