Ok so i got a 1994 lexus ls400 and its been sitting for a while. i did a oil change and changed the spark plugs the other day also i cleaned the iacv. It started but when it idles it sometimes shuts off it also shuts off when i try to touch the gas pedal.. could this be a fuel pump problem??

 

Did it run good prior to your maintenance? I'll be honest, I'm not sure with these cars but in my experience with other cars, when the fuel pump goes, the car just won't start. The pump just dies. I would check you work and make sure all is correct.

 

no it sounds like you put the wires on in teh wrong order or not firmly seated...

 

yea it ran fine.. someone told me today it could be the fuel pressure regulator..

 

the spark plug wires you talking about??

 

nah its not the wires i just checked them

 

I suggest that you check the gap on the spark plugs

 

Recheck you iac valve and gasket.

 

Check for un burn fuel (glowing catalytic converters) also it can be a ecu problem. I had a problem like yours when my car reach 1700rpms it would cut off I change the ecu now it rev all the way up. This just something to look at.

 

I have the same problem. My LS400 94 runs great when idle until I rev it beyond 1400 rpm and it wants to die. How do you know if the ECU is bad?

 

I had a cel and wasn't getting any codes so,that let me know I needed a ecu. I change the ecu and just so happen it fix that rev problem. Now it don't cut off when I give it gas but, it still have the lack of power like 4 cylinders . I replace my coils that fix everyone else problem. I guess next is to check the cam-sensor?