Sr22det breaking up under load (recent change)

[pjurisprudencia]

So my engines been acting up lately, trying to track down why it pops and breaks up under load. I just fixed my timing a few months ago since my intake cam was off a tooth. fixed it back to 11 links between cam timing marks. Fixed my lopey idle. Car ran great then started to feel like a fuel cut a month or two later or so under load. Thought plugs were fouled, swapped to new BKR7E’s. Plugs were actually showing lean conditions.
I have fresh 100 octane in the car almost every other day. So it can’t be bad gas. I am leaning towards failing fuel pump, walbro 255. it never broke up like this until recently, ambient temps have dropped tremendously though from 65-70 to 45-50’s, and again I did check if it was overboosting. I’ll be double checking my vacuum lines sometime this week and do an oil change as well. (VR1 race 10-30) will fix my AFR gauge to get proper numbers and going to check my coil pack ground and other engine harness grounds. Any input helps me heaps. I’ll double check my timing and plugs again.

https://uploads.tapatalk-cdn.com/20181228/9c231386f913642615da30850c0c0f42.jpg

Info on engine:
Hks sr22det
Tomei 256 poncams
Tomei adjustable cam gears
Hks gtrs turbo
Hallman boost controller set to fully closed to try and minimize boost pressure, didnt do anything since wastegate was still set at 14
Hks wastegate actuator, (boost gauge reads 14lbs) boost is off of wastegate atm.
NGK BKR7E
Walbro 255


Sent from my iPhone using Tapatalk

[jedi03]

Check your boost with another guage, buddy had same thing goin on, tuned for 18psi, even had tuner flown out to check everything...swapped boost guage and found out he was at 35 lbs...turned it down and stopped blowing out spark

[tuzzio]

Smart move checking grounds. Add more if you have to. You'll be surprised the weird shit it improves. Even if its just engine to chassis grounds.

Are you still on stock SR coils? Upgrade to k-series or LS coils. Stock SR coils suck.

[pjurisprudencia]

Check your boost with another guage, buddy had same thing goin on, tuned for 18psi, even had tuner flown out to check everything...swapped boost guage and found out he was at 35 lbs...turned it down and stopped blowing out spark



Yeah I did test hits on my way to work on the highway this morning. 14lbs were good, 16-18 psi is where I start breaking up. So I’m going to turn wastegate down and grab a new boost gauge and set it to 10-12 lbs for the winter time.


Sent from my iPhone using Tapatalk

[pjurisprudencia]

Smart move checking grounds. Add more if you have to. You'll be surprised the weird shit it improves. Even if its just engine to chassis grounds.

Are you still on stock SR coils? Upgrade to k-series or LS coils. Stock SR coils suck.



Stock sr20 coils, grounds seemed good so far, to be honest I may be blowing out spark passed 14 lbs.


Sent from my iPhone using Tapatalk

[jr_ss]

What is your gap? Close it up until it stops. Should be around .26-.28. Stock gap should be thrown out of the window on anything other than a stock setup. I second upgrading coils. Yes, the factory pieces work, however, they are now 20+yrs old.

[TheRealSy90]

I'd recommend z33 coilpacks over anything else as they are cheap, way newer, and plug into the sr coilpack harness. Simply have to re pin two wires on the coil plugs and delete the igniter.
Also, check the short fuel hose between the fuel pump and the pump hanger. I had a similar issue and that hose had a small split in it. They're old and usually not replaced when people change pumps.

[jedi03]

yup that's what happened to my buddy...the 35lbs was blowing out spark...turned it down to where he was tuned for 20lbs iirc, ran great after that!