S13 Black top sr20det hesitation under boost - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

RomulanS13 · 04-22-2018, 08:53 PM

I just did a black top sr20det swap on my 89 hatch. Wiring specialties harness and lower trans harness. I noticed a fine white sediment in my gas tank chassis had been sitting over 2 years prior to me owning it. I wiped down the tank the most i could replace with and isr pump amd got the car drivable. I didnt notice but the hesitation progressivly got worse the more i drove it.

I replaced the fuel filter with a fresh 300sx filter and like the tank it was full of white fine powdery chalky powder when it dries. So I decided to replace the fuel pump with a genuine walbro 255 old pump strainer was caked this stuff. Drove the car and same thing this time it sounded better but still has hesitation under load with boost 2psi or higher i havent even gone over 3 psi as it falls on its face and hesitates and sounds like a really bad missfire until i let off.

Checked for codes and it came out with code 34 knock sensor. I inspected the harness looks good so i replaced the knock sensor code went away but i get 55 to my knowlegde is no fault.

Checked for leaks but havent really done a real leak down test hust a visual on couplers and checked tightness on clamps. Im at a loss right now though i had it but back to square one. HELP.

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RomulanS13 · 04-23-2018, 10:52 PM

Update. Checked my fuel pressure and seems good but the stock fuel pressure regulator is failing probably one of the reasons for the hard start issue ive been experiencing. I hooked up an ebay FPR i had laying around and it worked. Boost guage hit 4psi highest ive seen before it leaned out and missed like before so im on the right track. I have a feeling the guage is wrong on this ebay FPR. Im going to raise the pressure and try it again.

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RomulanS13 · 05-07-2018, 07:28 AM

Update****
My hard start issue is finally gone. For my power I used a 6g amp wore kit to run my possitive lead from trunk and wasnt making good power also the amp draw was too great causing the positive cable to get too hot and popping my thermal breaker which in turn reset my ecu everytime it did this causing it to reset and give me a hard start. I replaced it with 2g amp wire and she passed the test. Fires up everytime no problems. As far as my hesitation im going to replace the coils and coolant temp sensor and go from there.

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04-22-2018, 08:53 PM	#1
RomulanS13 Join Date: Oct 2017 Location: near salty oceans Posts: 30 Trader Rating: (0) Feedback Score: 0 reviews	S13 Black top sr20det hesitation under boost I just did a black top sr20det swap on my 89 hatch. Wiring specialties harness and lower trans harness. I noticed a fine white sediment in my gas tank chassis had been sitting over 2 years prior to me owning it. I wiped down the tank the most i could replace with and isr pump amd got the car drivable. I didnt notice but the hesitation progressivly got worse the more i drove it. I replaced the fuel filter with a fresh 300sx filter and like the tank it was full of white fine powdery chalky powder when it dries. So I decided to replace the fuel pump with a genuine walbro 255 old pump strainer was caked this stuff. Drove the car and same thing this time it sounded better but still has hesitation under load with boost 2psi or higher i havent even gone over 3 psi as it falls on its face and hesitates and sounds like a really bad missfire until i let off. Checked for codes and it came out with code 34 knock sensor. I inspected the harness looks good so i replaced the knock sensor code went away but i get 55 to my knowlegde is no fault. Checked for leaks but havent really done a real leak down test hust a visual on couplers and checked tightness on clamps. Im at a loss right now though i had it but back to square one. HELP. Sent from my SM-G950U using Tapatalk

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04-23-2018, 10:52 PM	#2
RomulanS13 Join Date: Oct 2017 Location: near salty oceans Posts: 30 Trader Rating: (0) Feedback Score: 0 reviews	Update. Checked my fuel pressure and seems good but the stock fuel pressure regulator is failing probably one of the reasons for the hard start issue ive been experiencing. I hooked up an ebay FPR i had laying around and it worked. Boost guage hit 4psi highest ive seen before it leaned out and missed like before so im on the right track. I have a feeling the guage is wrong on this ebay FPR. Im going to raise the pressure and try it again. Sent from my SM-G950U using Tapatalk

05-07-2018, 07:28 AM	#3
RomulanS13 Join Date: Oct 2017 Location: near salty oceans Posts: 30 Trader Rating: (0) Feedback Score: 0 reviews	Update**** My hard start issue is finally gone. For my power I used a 6g amp wore kit to run my possitive lead from trunk and wasnt making good power also the amp draw was too great causing the positive cable to get too hot and popping my thermal breaker which in turn reset my ecu everytime it did this causing it to reset and give me a hard start. I replaced it with 2g amp wire and she passed the test. Fires up everytime no problems. As far as my hesitation im going to replace the coils and coolant temp sensor and go from there. Sent from my SM-G950U using Tapatalk