popping at wot!!!

[turbobuick87gn]

i took my car to the track last saturday and and everytime i went wot it started popping really bad... to 02 were lean at first at 715 so i add more fuel and broke to o2 up to 767..but it was still popping at wot...i could run the car the whole time 3/4 throttle and no popping but once i put it on the floor it starts popping...

does anybody have any ideas on what it could be?

i also have a problem with the car starting..some times it take me two key cycles just to crank it..just spins and spins...but once it starts it runs fine...any ideas on this to..

if you have any ideas please let me know

 

[TurboV]

Running too lean.. Need more fuel or more Octane.. Try posting some scan tool numbers so we can see more info. You need to lower your boost and start tuning from there or you will be asking us about head gaskets! What is FP at WOT?

 

[87NAT]

Ignition problem.

Crank sensor or ign module/coil pack issues.

 

[turbobuick87gn]

i've added overall 3.6 percent fuel through the chip...i'm at 19 pds...it does get about .5 knock after i added the 3.6 fuel..the blm was 131...int 128..af 05..vlts.13.9..ats 99....coolant...180..mal 00...cc 125...i think it needs another o2 sensor...these were at idle..at wot i got zero knock and 760 o2...still popping..how much more fuel do u think i need to ad...

also what do you think about the starting problem...it took me twice turning the key about 5 seconds to start the car...tps is a .44

anything else let me know...brett

 

[turbobuick87gn]

we were thinking coil pack...we think its blowing the spark out..how do you check the coil pack...brett

 

[jjkv]

Ignition problem.

Crank sensor or ign module/coil pack issues.

2x

john

 

[GNVYUS 1]

Since you have a Walbro, you should also have a way to read fuel pressure.

 

[SCOOBY DOO]

What was your fuel pressure at WOT?

 

[TurboDave]

we were thinking coil pack...we think its blowing the spark out..how do you check the coil pack...brett

Also check your plug gap. Should be .030 for higher boost like you're wanting to run.

 

[turbobuick87gn]

i don't know what the fuel pressure at wot is but i have a gauge on the fuel rail...i have the fuel pressure at 45 with the line off..when i crank it, it goes to 40 psi and stays there...it don't know if its 1 to 1 but i know in park i can go under the hood and rev it and it does raise with the rpms..not much cause there is no boost but it does move up..

the plug gap i believe i put it at a TIGHT .32 should i bring them to .30 and i'm running autolite 24s..are they good...

i don't think its running to lean cause the o2 are staying above 750 isn't that what its suppose to be.

if you need to know anything else let me know..

 

[TurboV]

Anything under 790 on the 02s is bordering lean. All cars are different, i just didnt want you to live on the edge until you get it right. Im suggesting you fatten it up, fix the problem, then tune from there.See if it will not break up at WOT if you turn down the boost a little, Maybe 16-17lbs. Did you pull a plug out and see hoe it looks? Try a spare coil pack if someone has a donor? 1 thing at a time.

 

[2QUICK2B6]

When my car did this i changed plugs coil pac an moduel an it hasnt broken up or poped since.

 

[turbobuick87gn]

alright tomorrow i'll try an bring it down to 17 pds and see if it still is breaking up...so if its not breaking up you think i should bring the fuel up then the boost..is my gap on my plugs at .32 to wide....i don't really know anybody with buicks around here so i don't know if anyone who has a coil..

i'm still learning first buick..thanks for all the help so far..

 

[TurboV]

Fuel pressure at 45lb line off is fine, the problem is you dont have a gauge to make sure your ok at WOT. If it still breaks up at 16-17lbs of boost, then i would consider a new coil pack and module. At least your 02s should rise and the car should run richer (safer). Check the plugs. They will tell you if your lean or fat, and make sure the gaps are correct. (Try tightening to .30) How old are your plug wires and did you have them off recently? Sounds silly, but double check everything, one thing at a time, and take your time.

 

[turbobuick87gn]

well the wires are accel 8.8 but they been on the car for about 5 years..the plugs are about 5 months old...i think i was going to replace the whole ignition system cause it all orginal anyways..

also do yall have any ideas about my cranking problem....

 

[jrv6gn]

I had the same issue yesterday coil pack wasn't grounded check for ground strap and make sure all bolts are tight securing the coil pack and mounting bracket.