S14 SR20DET rough idle and boost lag fix? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

1slowsilvia · 04-23-2013, 08:50 PM

So I went to change my spart plugs today with BKR7E plugs from autozone when I did the car ran SOOOOOOO rough. it already has a rough idle. sometimes it will idle perfect and some days it will miss then idle will drop will struggle and jump back up.

I was forced to put my old plugs back in to fix this issue and it ran ok ish. now why would changing the plugs do this? also before you ask YES I GAPPED THEM PROPERLY!

I just don't understand why idle constantly misses and car wants to die.

second issue is boost lag like BAD

I am running a S15 T28 Dual BB turbo.

It lags like a mother fucker I only build up 3 psi until I hit 4k then boost spikes and hits 8 - 9 psi and jumps around like crazy between 7 and 9 psi.

After driving my buddies stock S15 his is at full boost at 2400 rpms which is 7 psi. mine I brake boost at 3k it will go right to 3 psi and hold even at 3700 rpm it will go to 3 and hold.

Can this be a timing issue causing this?

I did a compression test came out 135 across the board.

The car did come with Tomei pon cams but had them switched for stock s15 cams same as s14.

I didn't do the change but the car runs fine but man it fucking is slow as fuck until 4k rpm and even then it doesn't rip like my stock S13 SR does.

WHAT THE FUCK IS WRONG????????

wiring can't be issue as I am runing Wiring Specialties S14 Kouki to S14 Kouki Sr harness.

Please help I can take video of it too.

my only thought is timing is off for it to miss like it does and run like pur fucking shit after changing plugs.
but some days it runs 100% normal please help. here is engine bay pic just in case you wonder where hoses are going.

04-23-2013, 08:50 PM	#1
1slowsilvia Zilvia Junkie Join Date: May 2012 Location: Palm Bay, FL Age: 37 Posts: 310 Trader Rating: (0) Feedback Score: 0 reviews	S14 SR20DET rough idle and boost lag fix? So I went to change my spart plugs today with BKR7E plugs from autozone when I did the car ran SOOOOOOO rough. it already has a rough idle. sometimes it will idle perfect and some days it will miss then idle will drop will struggle and jump back up. I was forced to put my old plugs back in to fix this issue and it ran ok ish. now why would changing the plugs do this? also before you ask YES I GAPPED THEM PROPERLY! I just don't understand why idle constantly misses and car wants to die. second issue is boost lag like BAD I am running a S15 T28 Dual BB turbo. It lags like a mother fucker I only build up 3 psi until I hit 4k then boost spikes and hits 8 - 9 psi and jumps around like crazy between 7 and 9 psi. After driving my buddies stock S15 his is at full boost at 2400 rpms which is 7 psi. mine I brake boost at 3k it will go right to 3 psi and hold even at 3700 rpm it will go to 3 and hold. Can this be a timing issue causing this? I did a compression test came out 135 across the board. The car did come with Tomei pon cams but had them switched for stock s15 cams same as s14. I didn't do the change but the car runs fine but man it fucking is slow as fuck until 4k rpm and even then it doesn't rip like my stock S13 SR does. WHAT THE FUCK IS WRONG???????? wiring can't be issue as I am runing Wiring Specialties S14 Kouki to S14 Kouki Sr harness. Please help I can take video of it too. my only thought is timing is off for it to miss like it does and run like pur fucking shit after changing plugs. but some days it runs 100% normal please help. here is engine bay pic just in case you wonder where hoses are going.