Mechanics

FUEL ISSUES

1985 Toyota MR2

Engine Mechanical problem
1985 Toyota MR2 4 cyl Two Wheel Drive Manual 130k miles

I am down to the last two possible problems with a fuel issue that I have been having. I have replaced the in tank fuel pump and a new in tank filter. EFI relay switch and fuses as well, along with a new external fuel filter. The only other thing that I can think of is the injectors or mass air flow sensor. How can I determine which of the two is actually the problem sense they both are outrageously expensive? Is there a test that a back yard mech. Can do to find out which of the two it is?
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Wkrizan
June 23, 2008.



What exactly is the issue you are attempting to resolve?

Dr. Hagerty
Jun 23, 2008.
If you're talking about No fuel to cylinders-inspect and test the circuit opening relay and MAF sensor-

When the MAF sensor grounds the Fc circuit of the COR this is when the fuel pump powers up-

Rasmataz
Jun 23, 2008.
I am getting fuel, after replacing the EFI relay switch, fuel pump and filters. She now idles fine but when I put her in gear there is no power to even get out of the driveway. So that is the problem, she idles fine but in gear she is starving for fuel push the clutch back in and it returns to normal idle. That is why I was thinking injectors or mass air flow sensor, unless I am missing something?

Tiny
Wkrizan
Jun 23, 2008.
Inspect and test the throttle position sensor-

Rasmataz
Jun 23, 2008.
Resistance reading for the TPS, throttle fully closed.2 throttle fully open 4.65 indicates bad TPS?

Tiny
Wkrizan
Jun 23, 2008.
Does anyone know if that is within specs?

Tiny
Wkrizan
Jun 25, 2008.
Adjust the TPS


http://www.2carpros.com/forum/automotive_pictures/12900_mrtps1_1.jpg




http://www.2carpros.com/forum/automotive_pictures/12900_mrtps_1.jpg


Rasmataz
Jun 25, 2008.
Does yours backfire through the intake? Does it do it all the time or intermittently?

I tried swapping MAFs and throttle bodies with known good units. That didn't do anything. Please let me know if you figure yours out and I will let you know if I figure mine out!

Tiny
Donutman1
Jul 11, 2008.