**SOLVED** Rough Idle, less responsive, CEL codes 25 and 26 less power 1FZ-FE 1994 (1 Viewer)

[Desert Dino]

@landtank is there a way to force the fuel pump to run at full speed under 2000 RPM just for diagnostics?

Maybe I got junk in the fuel system or the gas pump filter that is inside the fuel tank is bad, and running it in low speed dose not produce good flow and pressure?

 

[Irish Reiver]

Not yet They are in the OEM position In the long run I will move the O2 sensors to the PAIR location
in 2017 I got from Toyota Japan a recall campaign from 1995 that was preformed by a local Toyota dealer, although this rig was not imported to Israel by Toyota Israel and all was free of charge.

When you move the O2's to the exhaust manifold you will will only be 60cms away from the ECU. You likely will only need to shorten one of the cables and it is fairly easy to do.

@Irish Reiver we do not have the same problem I have issues you had bad signal or short disconnections between O2 sensors and ECM

Not sure if it is the same or not. I had the same the codes as you, both my O2s showed as working on Toyocom. The only thing I didn't have was the vibrations.

 

[BILT4ME]

@landtank is there a way to force the fuel pump to run at full speed under 2000 RPM just for diagnostics?

Maybe I got junk in the fuel system or the gas pump filter that is inside the fuel tank is bad, and running it in low speed dose not produce good flow and pressure?

Yes. You can pull the relay and short across two connections.

IDK which ones. I think @jonheld has a diagram.

 

[jonheld]

Yes. You can pull the relay and short across two connections.

IDK which ones. I think @jonheld has a diagram.

The 1994 EWD is in the resources section available to download free-fer-nothin'.

 

[BILT4ME]

 

[landtank]

To jump to high it’s 3-5. But looking at the diagram I’d suspect the open circuit relay as well. My daughters 93 Camry had hard starting and running issues and the open relay was the problem.

 

[TomH]

You should be able to jump +B and FP at the data port in the engine bay and provide 12V to the fuel pump. Please double check my work but I just went through this on my SC400.

This is from the 1994 EWD. My 1997 is different.

 

[Desert Dino]

Making the story short, it was the VAF sensor, replaced it with a used new one it solved the problem. I'll post later the long way we did until we found the problem.