Code 33 and possible solution
Thread Starter
Junior Member
Joined: Oct 2023
Posts: 43
Likes: 0
Code 33 and possible solution
Hi all,
I recently had a persistent Code 33 that didn't go away after replacing the MAF, relays, connectors, etc.
The solution in my case was a miscalibrated throttle position sensor (TPS). Code 33 will trigger if too much air flow is detected at 1/4 throttle (determined by the TPS) or less. In my case, the TPS was reading values too low, such that it was detecting too much air flow at a throttle position greater than 1/4, but the TPS believed it to be less than 1/4 throttle.
The solution was to set the idle screw at its minimum position. Then to set the TPS to 0.54V (read off the middle pin vs ground). Ideally minimum throttle should read 0.54V and wide open throttle should read 5V, but in my case I only got up to about 4.6V at WOT. Nevertheless I thought I would relay a possible solution to an aggravating error condition.
TLDR: don't **** with your TPS sensor. Back the idle screw all the way out, set the TPS to 0.54V, and never touch it again. The idle screw can be adjusted to prevent stalling, but do NOT re-adjust the TPS. Otherwise you can mess up your fuel-air ratio and trigger seemingly unrelated error conditions.
I recently had a persistent Code 33 that didn't go away after replacing the MAF, relays, connectors, etc.
The solution in my case was a miscalibrated throttle position sensor (TPS). Code 33 will trigger if too much air flow is detected at 1/4 throttle (determined by the TPS) or less. In my case, the TPS was reading values too low, such that it was detecting too much air flow at a throttle position greater than 1/4, but the TPS believed it to be less than 1/4 throttle.
The solution was to set the idle screw at its minimum position. Then to set the TPS to 0.54V (read off the middle pin vs ground). Ideally minimum throttle should read 0.54V and wide open throttle should read 5V, but in my case I only got up to about 4.6V at WOT. Nevertheless I thought I would relay a possible solution to an aggravating error condition.
TLDR: don't **** with your TPS sensor. Back the idle screw all the way out, set the TPS to 0.54V, and never touch it again. The idle screw can be adjusted to prevent stalling, but do NOT re-adjust the TPS. Otherwise you can mess up your fuel-air ratio and trigger seemingly unrelated error conditions.
Thread
Thread Starter
Forum
Replies
Last Post