PDA

View Full Version : S14 SR20DET Boosting Issues

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!

https://i.imgur.com/HYJty1O.jpg
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
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
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.