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Boost Gauge not working & running too lean

arthnox

Ready to race!
Hello everyone,

I am currently APR Stage II tuned on the 93 octane map. Last spring, I got a few mods done among which was a Podi boost gauge. The gauge worked for for awhile but it stopped functioning at the beginning of January. The stepper still works fine as the startup sweep still works. After startup though, the needles just stays at 0 PSI and doesn't move. I am therefore guessing the gauge is not getting any readings at all and 0 is it's default position. I blamed the cold but wanted to wait until spring to have a look, I am guessing one of the hoses disconnected.

A week or so after the gauge stopped working though, I started seeing something even more odd. A CEL got thrown for running too lean. I attributed it to either a bad batch of fuel or too heavy of a foot when the car was still cold. I decided to clear the CEL and wait to see if it happened again. Fast forward to this morning (a good 3 weeks later) and a CEL got thrown again on my way to work. I haven't had the time to check the code yet but I am willing to bet it's the same thing. It's pretty cold this morning (around 10F) and I left when the car was still cold but I dont feel like I pushed it or anything and my tank is almost empty so I am not gonna blame the fuel this time.

My question is therefore the following. Could a lose connection to the boost tap or anything else related to a non working boost gauge explain the CEL I am getting?

If not, what could possibly explain my engine running too lean? I have been stage II for 2 years without issues and now, after a boost gauge install (and a DV relocation kit which I forgot to mention...should be unrelated) as soon as it got below freezing in the morning, I started seeing issue almost immediately.

thanks alot for any insight you guys could provide.

P.S: Around the same time the gauge stopped working, I started observing that the engine was revving higher than normal when idle for a few seconds. When I stop at a red light, the engine stays between 1100 and 1300 RPM for a good 5 seconds before coming back down the 750-800 RPM. I never noticed that before and was wondering if it was normal or could be related to the issues I described above
 
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simpson110

Ready to race!
Sounds like a boost/vacuum leak. Follow hose for the boost gauge and I'm sure you'll find the problem. If you want to stop the issue and not investigate just remove the line for the boost gauge from where it is tapped and plug the hole.
 

arthnox

Ready to race!
a boost/vacuum leak could explain all problems listed? I figured it was a leak somewhere and since I am not pushing the car during winter time I figured it could wait until spring but the revving at idle is annoying and the CEL seem to indicate the mixture is not ideal, sometime bad enough to throw a CEL. I am guessing the engine is not running at peak efficiency because of that
 

simpson110

Ready to race!
Your get a code for lean a/f ratio and have a weird idle. Sounds like you are getting more air into your intact track than your car thinks.
 
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