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Discussion Starter · #1 ·
CEL came on yesterday code was PO299, described as underboost condition detected.

Engine running fine, plenty of power, no misfires. Reset light, code went away hasn't returned yet. Any ideas?
 

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Do you have the GFB DV+ installed by any chance? I got an overboost code one time and my tech said it was related to the DV+ - a momentary reading out of range. He was sure it wasn't anything to be concerned about.
 

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Discussion Starter · #3 ·
Do you have the GFB DV+ installed by any chance? I got an overboost code one time and my tech said it was related to the DV+ - a momentary reading out of range. He was sure it wasn't anything to be concerned about.
I do have the gfbDV+, but my code was UNDERboost. As I said, no difference in performance. Not overly concerned about it, but I will check all intake connections/vacuum lines etc...I have the Madness intake but everything there looked OK. I'll post again if the CEL comes back.
 

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I had this code, and had a distinct loss of power. Try making sure the electrical connector into the DV+ is properly seated. Its very sensitive, so even if it look like it is, give it a wiggle and press it in a bit more. Solved the problem for me.
 
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I do have the gfbDV+, but my code was UNDERboost. As I said, no difference in performance. Not overly concerned about it, but I will check all intake connections/vacuum lines etc...I have the Madness intake but everything there looked OK. I'll post again if the CEL comes back.
If you're getting the code and do not feel any kind of loss of power, check that the DV+ plug is secure and you may also consider greasing the spring inside the housing.

More importantly, the underboost DTC usually points to a vacuum leak, and usually results in a feeling of lost power. In this case, the best place to check is the wastegate solenoid (this is a 3-port solenoid with 3 vacuum lines, one of which goes directly to the wastegate so you can trace it back from there). Often times they use cheap plastic/rubber elbows to connect these lines to the ports on the solenoid, and they will crack and split in the creases. If you're not feeling a loss of power it may be that the leak is very small, but it will be worth it to check the connections. To see these cracks or splits you will have to actually take the line off of the solenoid to pull the elbows apart and look at them. Make sure the other connections from those lines are secure as well.
 

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Discussion Starter · #6 ·
Thanks for the input. Just checked the connector, and it was OK. Like I said earlier, there was no loss of power. The thing ran as it always did. Hopefully just a temporary glitch. Time will tell.
 

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Discussion Starter · #7 ·
Greg:

Thanks a lot for your insightful input. I will follow your suggestions, probably tomorrow ,saturday, and I'll report on anything I find. As an aside, when I bought my EC Clone some months back, you guys were awesome with tech support and fast replies, even on a weekend.

Your contribution to this forum is greatly appreciated. Your dedication to your product and to customer service are top notch.

Cheers.
 
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