Hesitates after 7lbs...

[FFPerformance]

Since when did afcs have sensors?

so you just randomly pull or add fuel without knowing the afr then?

Sorry I was making an assumption that a wideband was being used...

[crazy_skier]

try the plug wires.... i'd had this problem happen on my car and on my buddy's stock gst. Both times they were the plug wires and it would just get worse and worse

[Kracka]

Like lots of other people have said new, properly gapped, spark plugs will be the best place to start.

[xveganxcowboyx]

For rizzle. Until that's done we can stop speculating.

[b00stcreep21]

There's a million different things that could be wrong w/ it. You need to be more specific with what's happening. Internet diagnosis usually gets you nowhere, besides giving you around 6 different places to start.. Is it missing at 3500, or does it just stop trying to rev completley like if you turned the key off? Does it ONLY do it at 7psi, or just whenever it's at 3500 like at part throttle too? What do your a/f ratio's do when it's doing the issue?

[JET]

I'd have to disagree with you... spark plug basics 101, reading spark plugs.....

If you pull them and they are wet and black, then you are most likely too rich (possible oil consumption as well)
If you pull them and they are dry and white, then you are most likely too lean (as the original poster stated)
If you pull them and they are a 'toast' or tan color, then you are in the right area for an appropriate afr.

I would double check the wideband sensorys you're usuing to tune the SAFC and make sure that they are in working order. Perhaps cross check the wideband with one from a dyno? I can see how the safc could have been adjusting fuel based on what it thought was a rich reading, and causing a lean condition if the sensors are going out.... sometimes leaded fuel accelerates them wearing out too...

good luck!

$.02

Disagree all you want, it doesn't make you right. Also, it is difficult to really read a plug on a street car. To read a plug you need to shut the engine off immediately after a full throttle pull and then pull the plug, that is not really feasible on a street car. Also, it was never stated that the car had a wideband, so it likely doesn't. If you knew about DSM's, you would know that .035" gap is WAY too big and causes issues just like what was stated. DSM's are picky on the plug gap.

[Shane@DBPerformance]

White plugs means they are new plugs, not necessarily lean.

[xveganxcowboyx]

If you knew about DSM's, you would know that .035" gap is WAY too big and causes issues just like what was stated. DSM's are picky on the plug gap.


To add to this, they are also very picky about plugs in general. Make sure they are the OEM plug and not some fancy platinums or anything stupid like that.

[Scrmegl]

My car ran horrible on platinums. Do not use them.

[tpunx99GSX]

Sorry i forgot about this thread.
We tried new plugs gapped at .028, still happens, hes coming over this weekend and we will try some more shit like swapping wires, possible coil pack.
its a miss for sure. hes hitting fuel cut. DON'T RUN IT ANYMORE. you may need to advance the timing a bit. the car is leaning out not running too rich. if it were running rich they would be black and he would be puffin black smoke
Hes not hitting fuel cut at 7psi on 550cc injectors and a small 16g. I know what fuel cut feels like.