S14 SR20DET Boosting Issues - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

ArcherV2 · 10-11-2019, 12:01 AM

Just purchased an S15 Spec S with an S14 SR20DET Swap into it. It's running a Tomei D1 ECU with a funky mid-mount IC setup and remote HKS BOV but other than that relatively stock.

The trouble starts as I start to build boost, around 3.5K RPM @ wide open throttle, the car begins to throttle itself back and not want to boost anymore. My boost gauge works itself up to 0.5 KG and then sits there while the car begins to make a noise I can only type out as "brbrbrbrbrbrbr" while I feel an almost complete loss of acceleration. This happens in all gears, working my way through the gears at 50 - 60% throttle has no issues. It's only under heavy throttle that the problem appears.

Things I've checked:

Examined and cleaned the MAF
Replaced spark plugs and ensured coils are seated
Checked my IC piping and hoses for any obvious leaks/cracks

See my engine bay below!

S14rebuild · 10-11-2019, 06:38 AM

Check wastegate.....and or boost leaks

Dboyizmlg · 10-12-2019, 12:22 AM

Check actuator and make sure you have the clamp that holds the rod in place.

Also check you MAF, sounds like it can be MAF related.
Check for proper voltage

ArcherV2 · 10-17-2019, 09:48 AM

Quote:

Originally Posted by Dboyizmlg

Check actuator and make sure you have the clamp that holds the rod in place.

Also check you MAF, sounds like it can be MAF related.
Check for proper voltage

MAF has been removed and cleaned, this was my initial thought, I've already replaced the plugs but no improvement.

I'm being told it sounds more and more like a boost cut and I'll have to take a look at the actuator or potentially look at getting a tune.

jedi03 · 10-18-2019, 08:23 AM

is it just me or is the piping going into the throttle body not on all the way? looks like the lip is exposed on the right hand side of it...

S14rebuild · 10-18-2019, 11:19 AM

I thought the same....but figured maybe it was like that just for the pic.

ArcherV2 · 10-20-2019, 01:02 AM

Quote:

Originally Posted by jedi03

is it just me or is the piping going into the throttle body not on all the way? looks like the lip is exposed on the right hand side of it...

It's seated in there pretty tightly last I checked. I'm going to do a closer inspection on all the piping to see if maybe some of it is loose enough to cause issues when boosting.

Thanks for the suggestions guys.

ArcherV2 · 10-23-2019, 10:11 AM

Update: Piping is secure, no other obvious leaks are occurring. I am now looking into potential fuel delivery issues by replacing the fuel filter and cleaning the injectors.

Hopefully it doesn't end up being an ECU issue as I've had no luck finding anyone who can diagnose a Tomei ECU.

S14rebuild · 10-23-2019, 04:27 PM

Fuel pressure? Hook a guage up so u can read while driving and see what happens when the motor cuts out

jr_ss · 10-29-2019, 05:28 PM

Is the internal spring/metal coil in the turbo inlet pipe? You could be sucking that closed resulting in lack of boost and acceleration.

10-11-2019, 12:01 AM	#1
ArcherV2 Join Date: Sep 2019 Location: Toronto, Canada Posts: 14 Trader Rating: (0) Feedback Score: 0 reviews	S14 SR20DET Boosting Issues Just purchased an S15 Spec S with an S14 SR20DET Swap into it. It's running a Tomei D1 ECU with a funky mid-mount IC setup and remote HKS BOV but other than that relatively stock. The trouble starts as I start to build boost, around 3.5K RPM @ wide open throttle, the car begins to throttle itself back and not want to boost anymore. My boost gauge works itself up to 0.5 KG and then sits there while the car begins to make a noise I can only type out as "brbrbrbrbrbrbr" while I feel an almost complete loss of acceleration. This happens in all gears, working my way through the gears at 50 - 60% throttle has no issues. It's only under heavy throttle that the problem appears. Things I've checked: Examined and cleaned the MAF Replaced spark plugs and ensured coils are seated Checked my IC piping and hoses for any obvious leaks/cracks See my engine bay below!

10-29-2019, 05:28 PM	#10
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,052 Trader Rating: (34) Feedback Score: 34 reviews	Is the internal spring/metal coil in the turbo inlet pipe? You could be sucking that closed resulting in lack of boost and acceleration. __________________ My SR20VET

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10-11-2019, 06:38 AM	#2
S14rebuild BANNED Join Date: May 2019 Location: Florida-FAIL Posts: 2,497 Trader Rating: (8) Feedback Score: 8 reviews	Check wastegate.....and or boost leaks

10-12-2019, 12:22 AM	#3
Dboyizmlg Nissanaholic! Join Date: Aug 2011 Location: SoCal (I.E.), San Berdino, Colton, Redlands Posts: 1,665 Trader Rating: (17) Feedback Score: 17 reviews	Check actuator and make sure you have the clamp that holds the rod in place. Also check you MAF, sounds like it can be MAF related. Check for proper voltage

10-18-2019, 08:23 AM	#5
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,784 Trader Rating: (8) Feedback Score: 8 reviews	is it just me or is the piping going into the throttle body not on all the way? looks like the lip is exposed on the right hand side of it...

10-18-2019, 11:19 AM	#6
S14rebuild BANNED Join Date: May 2019 Location: Florida-FAIL Posts: 2,497 Trader Rating: (8) Feedback Score: 8 reviews	I thought the same....but figured maybe it was like that just for the pic.

10-23-2019, 10:11 AM	#8
ArcherV2 Join Date: Sep 2019 Location: Toronto, Canada Posts: 14 Trader Rating: (0) Feedback Score: 0 reviews	Update: Piping is secure, no other obvious leaks are occurring. I am now looking into potential fuel delivery issues by replacing the fuel filter and cleaning the injectors. Hopefully it doesn't end up being an ECU issue as I've had no luck finding anyone who can diagnose a Tomei ECU.

10-23-2019, 04:27 PM	#9
S14rebuild BANNED Join Date: May 2019 Location: Florida-FAIL Posts: 2,497 Trader Rating: (8) Feedback Score: 8 reviews	Fuel pressure? Hook a guage up so u can read while driving and see what happens when the motor cuts out