Dumping boost in third
#1
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Dumping boost in third
Ever since it got cooler a couple weeks ago, I'm dumping boost in third. First and second gear act fine, then shift to third and the boost will stay pegged for a moment, then drop to ~7 pounds and flutter just a bit. If I let off then hit it again, I can get full boost for another second before it dumps again. A short scan revealed no more KR than normal for my engine.
What'* going on? Overboost protection because of denser air?
What'* going on? Overboost protection because of denser air?
#3
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I have the same problem when I run a 2" pulley... This is one of the reasons I haven't been back to the track...
When I jump on it or even feather in the throttle (to WOT or not), boost will instantly hit 12-13 lbs. and then drop almost to ~7 lbs. and flutter. I can't even get up to full RPM (full boost) with out it doing this. The first few times it did this I thought that I had bad belt slip but I was wrong...
When I jump on it or even feather in the throttle (to WOT or not), boost will instantly hit 12-13 lbs. and then drop almost to ~7 lbs. and flutter. I can't even get up to full RPM (full boost) with out it doing this. The first few times it did this I thought that I had bad belt slip but I was wrong...
#4
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Is this problem only seen on stock PCM'*? By doing the 'boost bypass' trick solve this problem? I know the 'boost bypass' isn't the safest thing but I'm out of Ideas.
#6
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Ok so this is happening on stock and Hypertech chips, are any Jet chips having problems with this?
Also what exactly has to be done to do the 'boost bypass' trick. With this done all I have to look out for is hitting the gov. and rev. limiter? Right? If not what else?
Also what exactly has to be done to do the 'boost bypass' trick. With this done all I have to look out for is hitting the gov. and rev. limiter? Right? If not what else?
#8
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Take the vac line off the bottom of the BCA, pluge the hose if you feel so inclined, but not the open port on the BCA.
Let off a little when it'* gonna shift.
Let off a little when it'* gonna shift.
#9
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Little update: after seeing rich readings on my A/F gauge, I backed the AFC off a couple percent, which seemed to reduce the boost loss. I think the boost dump was triggered by high MAF readings. Why only in third, I don't know. I'm gonna research a Jet chip or a custom one. It seems Hypertech did not foresee this complication.
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