popping help needed

[LV TTA#996]

I need help!! Here's the scoop- car pops when I get on the throttle, happens at 10lbs of boost in 1st gear everytime. Then, if I get into 2nd or 3rd and floor it, no popping. Connected turbolink, O2 volts are between 650 and 880 at idle, no cross counts (but I just put an O2 sensor in about 6 months ago) When driving, cross counts move a little, but not much and the O2 volts are still high. Car is running rich (I smell the exhaust). Is this a bad O2 sensor (so soon after putting it in without EVER using race gas?) The knock was only 5.4 at its worst, but this came at 3300 rpms. I was getting 3-4 degrees at 2800 rpms, half throttle. What do I do, I checked fp and it is 44 at idle (Thrasher chip for blue tops). Is this a vacuum leak? Bad O2, cam sensor? Help!
Danny TTA#996

 

[Superman]

<BLOCKQUOTE><font size="1" face="Arial, Helvetica, sans-serif,">quote:</font><HR>Originally posted by LV TTA#996:
I need help!! Here's the scoop- car pops when I get on the throttle, happens at 10lbs of boost in 1st gear everytime. Then, if I get into 2nd or 3rd and floor it, no popping. Connected turbolink, O2 volts are between 650 and 880 at idle, no cross counts (but I just put an O2 sensor in about 6 months ago) When driving, cross counts move a little, but not much and the O2 volts are still high. Car is running rich (I smell the exhaust). Is this a bad O2 sensor (so soon after putting it in without EVER using race gas?) The knock was only 5.4 at its worst, but this came at 3300 rpms. I was getting 3-4 degrees at 2800 rpms, half throttle. What do I do, I checked fp and it is 44 at idle (Thrasher chip for blue tops). Is this a vacuum leak? Bad O2, cam sensor? Help!
Danny TTA#996<HR></BLOCKQUOTE>

Danny, you're running 44psi at idle with the vacuum line connected? that's too high! have you changed anything recently? you may have a vacuum leak or your fuel pressure is adjusted wrong. it hould be 45 psi at idle with the line off. line on, the fuel pressure should drop because of the vacuum on the regulator. just my guess. hope i am explaining this correctly.

russ

 

[Superman]

ok,
sorry!

 

[LV TTA#996]

<BLOCKQUOTE><font size="1" face="Arial, Helvetica, sans-serif,">quote:</font><HR>Originally posted by Superman:
Danny, you're running 44psi at idle with the vacuum line connected? that's too high! have you changed anything recently? you may have a vacuum leak or your fuel pressure is adjusted wrong. it hould be 45 psi at idle with the line off. line on, the fuel pressure should drop because of the vacuum on the regulator. just my guess. hope i am explaining this correctly.

russ<HR></BLOCKQUOTE>

No, the FP is 44 with the vacuum line removed...

 

[Turbo TA MAN]

Check your coil pack, try another one,mine did this too. Even though resistance was okay on coil pack.Tryed the one on my grand National and solved the problem,this sounds like classic coil pack problem. Good luck,
Bob

 

[2QUIK6]

Wow, if you're not seeing any O2 cross counts, then your O2 is dead, unless it is in open loop and not warmed up yet or at WOT.
Otherwise at hot idle you should see xcounts go from 1-255 in less than 90 seconds, if not, need a new one.
If O2 is showing rich, then its cutting fuel, causing it to run more lean, agin could be the O2 bad.
*
If you have a vacuum leak, then you should see your BLM# at idle be way high, like above 140 or 150, that would then need to be fixed. High BLM at idle could also be a bad PVC valve.


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Rob
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