Bogs when accelerating then shuts off

DEVAN NICHOLAS STERMER

MEMBER
1993 SUBARU SVX
4.0L
6 CYL
2WD
AUTOMATIC
250,000 MILES

When it's a cold start it'll do better than when it reaches normal operating temperature. But kinda all around the same issue and that's when I go to accelerate it just dies unless I give it the smallest amount of gas I mean tiny like barely any and slowly too. It'll go but only gets into second about 35 mph or so then drops the acceleration all the way to 100 rpm's and then shuts off.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

This sounds like either a fuel issue or an input sensor issue like a throttle/idle switch.

First thing is let's check for codes. If there are no codes then I would suggest start narrowing this down by checking fuel pressure. If fuel pressure is okay then we need to test the throttle sensor.

This is a potentiometer sensor which means if we monitor the voltage it will increase and decrease as we operate the throttle blade. If the voltage gradually increases and decreases then it is operating properly. If it jumps around or skips up and down quickly then the sensor is most likely the issue.

However, I included the process on how to adjust it. We should perform this as well before replacing it. Let me know if you have questions. Thanks

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Images (Click to make bigger)