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Turb
02-24-2016, 06:29 PM
So I finally go my sr20det back together blowing and changing the head gasket, it starts up fine, idles fine, and besides a little lifter ticking doesn't sound bad at all.

But... when I took it out to drive it for some reason it just doesn't have power it hits full boost at 2500-3000 ish rpm but kinda bogs down just feels like its really sluggish? Any ideas on what it could be? Checked all my plugs look good running a little rich but nothing major, turbo is in good condition no shaft play, could it be major boost leaks?
Possibly timing?
What do you guys think, I should check?
Thanks.

Tyler_240
02-24-2016, 06:36 PM
Verify your base timing, check your MAF (Clean it very carefully) and you can use carb cleaner around your IC piping and if it changes the idle, you know you got a boost leak...

Turb
02-24-2016, 07:35 PM
What do you mean if it changes the idle? like when I spray it at my couplers or week spots in my boost system?

KAT-PWR
02-24-2016, 09:09 PM
Lack of power and rich sounds like the knock sensor is being tripped. Check timing as mentioned. Do a boost leak test.

FaLKoN240
02-24-2016, 10:19 PM
You sure it's lifter tick and not an exhaust manifold leak?

!Zar!
02-24-2016, 11:17 PM
Sounds like a loose exhaust manifold/turbo.

Tyler_240
02-25-2016, 04:32 AM
What do you mean if it changes the idle? like when I spray it at my couplers or week spots in my boost system?

Correct. I didn't think about the knock sensor, but that's not a horrible idea. It's located underneath your intake manifold way up on the block. You can unplug the harness temporarily.

If you have solid mounts, it could be receiving false knock and retarding your timing from the vibrations.

corkscrew
02-25-2016, 05:20 AM
Same thing happened to me. Knock sensor. Go check the ecu for codes

Turb
02-25-2016, 07:01 AM
It could be loose exhaust mani or elbow I have like 2 studs on my elbow

thegr8one013
02-25-2016, 09:06 AM
is hitting full boost at 2.5-3k normal? was this the same as before?

if you were hitting full boost at an earlier rpm before it could be a boost leak somewhere. if theres no boost leak it could be a mechanical timing issue.

i havnt dealt with sr20s but if their cas are adjustable then it could be ignition timing being off.

Turb
02-25-2016, 12:23 PM
ECU threw code 55 so I assume its not my knock sensor?
Ill check for boost leaks and exhaust mani

Kingtal0n
02-25-2016, 04:21 PM
probably timing setting or knock sensor as many have already suggested

Turb
02-25-2016, 07:26 PM
Well since I set my timing to spec off the fsm and the ecu threw no codes for knock sensor it's probably not that...

Tyler_240
02-25-2016, 07:49 PM
What we're saying about the knock sensor, is only going to be a problem with at speed...if its the problem...sounds like you have some other maintenance issues, a.k.a. fix those exhaust studs...if you have a solid mounts, or a lot of vibration at WOT, that is when the knock sensor is going to act up and retard your timing

Kingtal0n
02-25-2016, 07:56 PM
You cant go by codes. they help sometimes but... put it this way, Ive never checked a code on an Nissan. Ever.

Turb
02-25-2016, 08:35 PM
So only way to know if my knock sensor is bad is by replacing it..?

corkscrew
02-26-2016, 07:07 AM
A lot of the time something in the sub harness will go bad

corkscrew
02-29-2016, 05:47 PM
Ever figure out the issue?

mando240
03-16-2016, 03:42 PM
So only way to know if my knock sensor is bad is by replacing it..?

I am curious to know if you got the issue under control.

Turb
03-20-2016, 01:32 PM
Looks like the new cometic headgasket I got is garbage and need to get a new one