Jump to content

G4x and 3bar Map Sensor problem


Recommended Posts

Hey all, I am looking for some advice.

I recently purchased a V1-2 WRX Plugin G4x ECU along with an expansion loom, IAT, and 3bar map sensor. I have installed it all and been dyno-tuned by Keith Stuart.

I have only 1 Problem while on the dyno we stopped and had a lunch break. When we got back, we started the car and found it was idling very rough and would try to die. The map sensor reading was stuck reading around 30kpa while the engine was off, only ACC on. While sitting there with the accessory on we could watch the map sensor readings slowly climb back to 100kpa over the span of 30-45 minutes. Once the MAP readings were back to 100kpa engine and tuning went perfectly.

My tuner was confused and said he hadn't seen this before.

It has since happened 5 or so more times, usually after longer trips (30 Minutes plus) but has happened once on a short trip. I have not noticed any patterns as to what could cause this, nor have I found anything similar online.


So long story short, has anyone else had anything similar or have any ideas? Or perhaps is it just faulty.


Attached is a short video of the issue in progress. In the video, the engine is off with only accessory power.


Thanks for any help!

Link to comment
Share on other sites

I believe we had some faulty MAP sensors recently, I dont know much detail of the symptoms that were reported but yours sounds like it could be faulty so I suggest you email tech support to bounce it off them.  There are not too many other explanations that would fit.  

Link to comment
Share on other sites

Thanks guys.

Forgot to put in the post that I have checked for blockages and kinks. I ended up replacing the line. I have also tried removing the vacuum line off the sensor and running it straight to atmosphere, but it still read low.


I will contact tech support and see what they think.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...