rb25 random hard start

[Skym]

Oh, ok. When you mentioned spark blowing out, I thought sparkplug gap is too wide (1.1mm vs 0.8mm). It also could be using wrong heatrange (PFR7A is used with exhaust, etc mods, PFR6A should be stock for RB25DET). The rpm where you mentioned it happened, did the same on my car when sparkplugs were at incorrect gap, heatrange (2x coilpacks failed). There is a way to increase power to coilpacks via ECU retune (adjust tables), but factory tend to set it up for longevity of coilpacks. There's a safety rev limiter (fuel cut) at around 5000rpm, but I think only engages with 0km/h on speedo and shouldn't go above 5000rpm.

[evolution23]

Oh, ok. When you mentioned spark blowing out, I thought sparkplug gap is too wide (1.1mm vs 0.8mm). It also could be using wrong heatrange (PFR7A is used with exhaust, etc mods, PFR6A should be stock for RB25DET). The rpm where you mentioned it happened, did the same on my car when sparkplugs were at incorrect gap, heatrange (2x coilpacks failed). There is a way to increase power to coilpacks via ECU retune (adjust tables), but factory tend to set it up for longevity of coilpacks. There's a safety rev limiter (fuel cut) at around 5000rpm, but I think only engages with 0km/h on speedo and should'nt go above 5000rpm.

i pulled bcpr6es plugs out that were gapped at .8 and placed in bkr7e plugs gapped at .8 so i went one heat range colder right?

Anyways put the stock BOV on today and with the new plugs had a chance to get the car under load at WOT, its better but now instead of just a constant hesitation, its lurchy. It feels like its boosting on/off/on/off/on/off at first i thought it was me getting shaky in the foot but its the car. Im going to put in the walbro pump as soon as i get my driveway back which should be 20 mins or so. I will see what that does.

[Skym]

Not familiar with those part numbers, but the 6 to 7 in part number is probably the heatrange.

Have you checked for airleaks around MAF????? When there's a airleak near MAF (usually loose intake hose clamp), engine can start stuttering which is similar to a failed coilpack.

[evolution23]

Not familiar with those part numbers, but the 6 to 7 in part number is probably the heatrange.

Have you checked for airleaks around MAF????? When there's a airleak near MAF (usually loose intake hose clamp), engine can start stuttering which is similar to a failed coilpack.

yeah we have smoke tested and pressure tested compression tested the cylinders, etc.. BUT i am extremely happy to say the car is running great now, fires up a lot quicker, no hesitating on WOT, noticeably more power. it was indeed my fuel pump. Currently is set at 43psi with vac line disconnected, drops to just between 34/35psi with the vac line connected. I put the stock pump filter on the walbro as well so it can reach into the bottom 1/4 and i clamped the pump to the bracket so it doesnt fall seeing as its a fair bit smaller than the stock pump.

[Skym]

Good to hear.

[evolution23]

Good to hear.

its kind of shocking how much more power the car has now but yes i am very glad that i finally got it running nicely. Thanks for all the help everyone!