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My car wont make more than 10-11lbs of boost (JB4 Log Check issues?)

G70LEbyAdoom

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Hello! I was wondering if someone who is better at reading Logs than I am could help me out.

In the last week or so, my car has been feeling slower than usual, so I Took some logs with my JB4. Turns out, besides the fact that my timing is horrible now on the same gas that used to net me 0.8's/1.5's at most across the board, is now reading anywhere from 3.8's to 5.3's, But no matter the map I am on, my car only makes 10lbs of boost instead of the stock 12 to 14, which yields only 15 to 16lbs of boost in map 2 and map 3.

No CEL's are present, I have the plugs that are recommended from the JB4 450hp kit, They are gapped correctly, and I always use the same station for gas.

I have already tried the ECU reset trick via disconnecting the battery and that did not work. I would think maybe a vacuum leak, but then it would not make the added boost from the JB4, Unless my understanding of how it works is wrong. Please advise, as any guess is as good as mine.
Map 2 and Map 3 logs attached below.
 

Attachments

Adjust your FF/wastegate adaption on your user adjustment on the jb4. Set it to 25. I had the same issue. Now I get 17 psi of boost. That will only work if you have the wastegate wires for the jb4. It's purchased separately for 140 well worth it. Good luck. Also I run it on Map 2
 
Adjust your FF/wastegate adaption on your user adjustment on the jb4. Set it to 25. I had the same issue. Now I get 17 psi of boost. That will only work if you have the wastegate wires for the jb4. It's purchased separately for 140 well worth it. Good luck. Also I run it on Map 2
I dont believe thats the issue, as a few weeks ago I was making 19lbs of boost no problem.
 
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If that doesn't work I will give you the email to the customer service for jb4.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
They will certainly help you. Good luck brother. Keep me updated
 
They will certainly help you. Good luck brother. Keep me updated
I will for sure, Though I would be surprised if Terry doesn't respond to this, as he is constantly monitoring the forum. or at least was.
 
I will for sure, Though I would be surprised if Terry doesn't respond to this, as he is constantly monitoring the forum. or at least was.
He's amazing. Got me up an running. Dyno tested my car Monday. Made great power.
 
______________________________
From interior to exterior to high performance - everything you need for your Stinger awaits you...
Hello! I was wondering if someone who is better at reading Logs than I am could help me out.

In the last week or so, my car has been feeling slower than usual, so I Took some logs with my JB4. Turns out, besides the fact that my timing is horrible now on the same gas that used to net me 0.8's/1.5's at most across the board, is now reading anywhere from 3.8's to 5.3's, But no matter the map I am on, my car only makes 10lbs of boost instead of the stock 12 to 14, which yields only 15 to 16lbs of boost in map 2 and map 3.

No CEL's are present, I have the plugs that are recommended from the JB4 450hp kit, They are gapped correctly, and I always use the same station for gas.

I have already tried the ECU reset trick via disconnecting the battery and that did not work. I would think maybe a vacuum leak, but then it would not make the added boost from the JB4, Unless my understanding of how it works is wrong. Please advise, as any guess is as good as mine.
Map 2 and Map 3 logs attached below.
You should start with updating your firmware.
 
Never mind, I skimmed your post instead of reading it.

For comparison my ECU_PSI reads 10.5-12 and boost 14.8-16.3 on MAP2 with gear 2 being a bit lower for both than gear 3. I do not have my EWG wires installed.

I am also seeing the ECU pull back throttle in your logs when the pedal is 100% during your wot pulls. That also suggests maybe your gas isn't quite good enough.

My throttle never drops when the pedal is mashed and my IGN2-6 have only one 2.3 blip in IGN4 for the pull. I run stock plugs and Costco 92 octane.

My brother has a lot of ING2-6 events on Densos and Canadian 91 octane with just map1. I have seen a few other more active IGN2-6 logs with Densos where octane should be sufficient for the map. Not enough data to draw any conclusions from but interesting enough to keep looking into.
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
Never mind, I skimmed your post instead of reading it.

I am also seeing the ECU pull back throttle when the pedal is 100% during your wot pulls. That also suggests maybe your gas isn't quite good enough.
Which lines are you seeing that at and which log? ive never noticed that
 
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Which lines are you seeing that at and which log? ive never noticed that
MAP2 log ending in _2208

First pull lines 306-308, 343-347, 379-394

The last one (379-394) the throttle drops to 30 and boost to 0 while while pedal still 99-100. Very weird.

MAP3 ending in 0746

First pull lines 409-410, 437-442

Second pull 702-710, 732-737
 
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The ECU is load based not boost based. During cold weather it will target a lower boost level to make similar power. IAT is down around 50 so the boost numbers seem plausible.
 
The ECU is load based not boost based. During cold weather it will target a lower boost level to make similar power. IAT is down around 50 so the boost numbers seem plausible.
So this is actually normal? Is there any way to get my boost back? I miss the speed!
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
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