7MGTE starts, runs for 7 seconds and then dies

[supralee]

87 auto 7MGTE swap to an 84 manual. Got the 7MGTE to start, sounds like it misses. Runs and idles fine for about 7 seconds and then dies abruptly, sounds as if the fuel is getting cut. If I give it gas, it revs to and tops off at 2000 RPM and after releasing the pedal it tries to idle and then dies immediately afterwards. Thought it might have been the AFM, replaced it with a different one from a friend, but there were no changes to the symptoms.

I'm pulling a code 51, replaced the TPS with another one which was adjusted correctly. The previous TPS kept getting stuck in the open position. After replacement, I'm still receiving the the code 51 error. Code 51 also refers to a state with No NSW signal which lets the ecu know that the auto tranny is in park or neutral.
The starter is the original off the 5MGE to keep the wiring for the reverse light switch which might be the reason why it starts with No NSW signal. The NSW signal leads to the ECT ECU.
Checked voltage at ECU plugs. Everything is within spec except IDL which reads 6v with the IGN ON and throttle open. Spec is 10-14v
Jump Fp and B+ at check connector but still no differences.

Since the 7MGTE came from an auto, will the neutral start switch have anything to do with the issue?
Where is the neutral start switch?
Does this mean I need to hook up the ECT ECU in order to get the NSW signal to the ECU?
Why would the voltage be lower and what can I do to solve that problem?
Wiring diagrams show that the ECT ECU has an output IDL which interconnects with the IDL leading to the TPS could this have anything to do with the lower voltage reading?

The problem seems similar to having the AFM unplugged but I'm nothing getting a code for the AFM. This also makes me wonder, is there any one with a 7MGTE swap in Colorado?

Any help would be greatly appreciated!

 

[mnracer550]

idk how neutral safty switch could have anything to to with it. it shouldnt even let it start if thats the issue. have you checked ur fuel presure?

 

[MINA]

i had the same issue did you make sure the tps is all the to the closed position if you were looking at turn it all the way to the right (counter clockwise) see if 51 goes away its real time code so you can do this while the switch is on.

as far as you car dying you didn't mention anything about timing check timing and igntion timing you need to make sure you are on the money with the cps (cam position sensor).

51 means:
a/c switch could be on during code retrieval
open throttle position during code retrieval
and something with your car being in neutral

 

[mkiiSupraMan18]

*removed*

 

[89supracrazy]

Cold start injector will let it run for a about 5 seconds or so. I believe you need to figure out why your injectors are not working. I believe that is where your problem is.

 

[supralee]

MINA, tried the throttle trick you suggested, no changes. The timing is correct. The ignition timing is the base setting to get the started. I can't set ignition timing since I don't have enough time to and also since I have a code 51.

The pins at the ecu for all injectors were reading at specified voltages while the IGN was ON. I'll have to put the individual injectors on the list to check for sure though.

Also just found that I jumped the A/T indicator switch. Alright found that neutral start switch connector. It is a round yellow F plug with the two wires needing to be connected, black and white, and black and blue. The black and white had 12v with the IGN ON and the black and blue had no voltage. Jump those two wires and no differences. So it looks like I might have to try a different TPS.

 

[MINA]

darn well go ahead and try a new tps
i will follow up on this

 

[89supracrazy]

Make sure the injector resistor pack is plugged up and check the resistance on the resistor pack. If you resistor pack is bad you will not get no power to the injectors. You can eliminate the fuel pump and the afm because the fuel pressure is good if the cold start injector is working and the afm you said you could rev it to 2000 rpms. If you unplug the afm it will not rev at all just idle. I believe I would start with the resistor pack and see if it is with in spec. The tps you can unplug and it will idle around 1500 rpms. Also check all the fuses in this diagram.


http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=111

 

[whitemike]

Does the car stay alive if you keep the throttle open just a tad?

 

[nightrider760]

that sounds like the issue i been having for years can someone resolve this plz

 

[supralee]

89supracrazy - I've check to makes the injector resistor pack is plugged up and resistance is in spec. I'm going to double check it tomorrow after work again.

So you're saying that with out the AFM it won't rev? And with the TPS unplugged it will idle at 1500 rpms? I'm going to check that out tomorrow to help rule out the both. But doesn't the fuel pump come on initially when you turn the key to ON which runs the CSI? And after a certain time it shuts off and runs from signaling from the ECU?

I jumped Fp and B+ at the check connector and turned the key to IGN ON but couldn't hear the fuel going through the lines, either that or I need a hearing aid. I jumped IDL and E2 through the engine harness and the code 51 turned into a 41. So looks like the problem is the TPS. Which makes me wonder

Doesn't Fp have power when IGN ON?
Jumping the IDL and E2 grounds IDL and gave me a code 41 but isn't that what the TPS does from throttle closed to the 0.9mm clearance to begin with?

 

[89supracrazy]

The fuel pump will not turn on until you crank the engine. It will turn on if you jumper the fp and b+ in the on position at the check connector like you said. You probably won't hear the fuel pump. Without a fp guage you would not know. I tried that with my old fuel pump and I could not hear it. I can unplug my injector resistor pack and it will run for about 5 seconds or so. You need to check to see if you are getting power to the resistor pack. Look at the diagram I sent you and see if you are getting 12volts to the resistor pack. Try this link also. Make sure you have 12 volts on the black/ with orange strip. You have to be getting fuel pressure to the rail or the csi would not work. Your tps is still not adjusted correctly. Did you use a filler guage between the throttle stop screw. You have to use the filler guage or it will not work. The 0.9mm is right but you need the filler guage.


http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=46

 

[supralee]

I used a feeler gauge to adjust the TPS, but I'll readjust to make sure it's correct. For the resistor pack, you mean the EFI resistor? And I should be looking for 12v at Pin 2 black with red stripe wire with IGN ON correct? I think I might have found the culprit. Fp from the 7MGTE ECU which is the yellow wire from the Q plug pin 7, leads to the B1 plug pin 6 and stops there. I don't have the 84 TEWD, but I do have the 85 TEWD is the wiring different for those years? There are two chassis plugs where that wire should be patch into. But I'm not sure where it should go to. If someone could tell me that would be great.

 

[89supracrazy]

When you jumper the fp and b+ at the check connector, turn your key to the own position and put your hand on the fuel pressure regulator and see if you feel the regulator moving up and down. If you do you can rule out the fuel pump for now. The regulator is located right behind the alternator. I think you are on the wrong track. If you are still thinking about power getting to the fuel pump your csi will not work. I might be wrong but it is either the cps that controls the injection or the power feeding the resistor pack. The computer sends the negative to the injectors when it is at the right time. If you rule out that the resistor pack is getting the voltage, then I would check the cps specs. Good luck

 

[supralee]

I'm an idiot, I should have thought of this earlier. I jump the fuel pump check connector on the 5mge chassis harness and the car is running. Its a rough idle which might be do to the ignition timing.

This isn't going to be my permanent setting, so how does the 5mge fuel pump run through the 7mgte ECU?