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Check Engine Light, ESP Light, And EPC Light

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Check Engine Light, ESP Light, And EPC Light

Old 11-30-2009, 09:12 PM
1st Gear
Thread Starter
Join Date: Jan 2008
Posts: 83
Unhappy Check Engine Light, ESP Light, And EPC Light

I was recently driving minding my own business when all three of those lights suddenly came on. And my turbo stopped responding.
I pulled over checked all my vaccume, and air lines. They're all just fine.
I unplugged my MAF sensor to check and see if it was that nothing changed.
I then unplugged the sensor to my n75 valve and every thing started working again. The ESP light went away and so did the EPC light.
Check engine light stayed on obviously.
I thought it was maybe just a glitch for the sensors going out. So I reset the check engine light.
And this time just the ESP and EPC lights came back on. So I tried with the MAF sensor, which put the CEL back on. And it didn't change any thing again.
So I figured I'd just do what I did last time and pull the plug from the n75 sensor again. This time, all the lights stayed on and I didn't get my boost back.

I'm trying to figure out what the hell is going on.
I'm fairly certain it isn't my MAF sensor.
My n75 valve could be a problem however it doesn't really make sense that it puts my car into "safe" mode when it's unplugged.
I don't see how it could be my Trottle Position Sensor since the car doesn't idle rough, or high, it doesn't choke. It simply runs as if there were no turbo.
I don't see how it could be my Coil Packs since the MIL light isn't on.
I have thought about maybe my intercooler sensor, however I've had that sensor do it's job and the EPC light never came on.

I know there are a few more options of what it could be. I just need help narrowing down what it might be.

Thank you.
Old 12-02-2009, 12:52 PM
2nd Gear
Join Date: Mar 2007
Location: Richardson, TX
Posts: 1,181

Did you check the codes??
Old 12-02-2009, 09:44 PM
Dan1969's Avatar
3rd Gear
Join Date: May 2009
Location: South Korea
Posts: 1,682

Please scan it, sounds like a hell of a problem...
Old 02-23-2010, 09:57 AM
Junior Member
Join Date: Jan 2010
Posts: 1

All, just wanted to add my 2 cents. I had the ESP light come on when driving (no other check engine lights at the time). After turning off the car (IE: gassing up or quick stop over) the light would reset but then come on again. I read in other forums to check the brake light switch. FYI: My brake lights worked fine but for some reason, it tripped my ESP light. I changed the part ( ~ $5) and have not had the ESP light come on since. (knock on wood). Just wanted to share that. Peace!
Old 02-23-2010, 06:31 PM
1st Gear
Thread Starter
Join Date: Jan 2008
Posts: 83

Wow old post. I completely forgot about it.
I never got the codes for it because the light continued to be a on and off deal. The ESP light never returned.

I discovered my DV had stopped working. And was confusing the hell out of my car apparently.
I've changed it and haven't had a problem since.

And I do have a problem with my car telling me that my brake lights don't work. Never thought of the brake light switch.

Thanks guys
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