red top sr20det stumbling under load but revs fine. please help!

[nissanguy93]

Hello all,
My redtop sr20det w/t28/stock injectors,maf ect is cutting out in low RPMs when in boost and engine is under load. No boost leaks found but it was supposed to be on 12lbs, noticed it hitting 15 on the boost gauge but no mbc found, just a safc. I replaced the plugs with ngks gap is .30, and i put another set of coil packs on. Im smelling fuel when getting on it and shifting into 2 at low rpms it bucks alot. Mainly though when im cruising and need to pass someone or going up a hill and get down on it and build boost it just hesitates and cuts out and i have to baby the throttle to get it to even pick up speed. It drives fine out of boost but as soon as i start building boost it just hesitates and doesn't want to pick up. Idles a little high, around 1k and not completely steady but doesnt drop dramatically or try to stall. I searched but couldnt really duplicate my problem. Can one of you sr gods point me in the right direction or anyone had the same problem? Thanks in advance and any helps appreciated.

[OnTheChip]

How's the fuel pressure?

[hessianben]

Check your ignition timing before you proceed. I assumed I had a boost leak too- same symptoms. Turned out I was like 5* too advanced somehow? Easy fix.

[nissanguy93]

Okay, ill check the ignition timing.

[nissanguy93]

Ill check my ignition timing. The guy said is running 12psi, when the boost gauge says 15 but i can find a boost controller on it. How could it be running 15psi?

[ultimateirving]

Check plug gap too. Gap them to .028-.032. You want it as wide as possible without blowing out.
And locate the wastegate actuator, follow the vacuum line going to it and see if it connects to the turbo/intercooler piping or to a boost controller.

[Mikester]

If you're smelling fuel when getting on it, there is a leak somewhere- the lack of power could be that your car is leaning out. You shouldn't smell raw fuel.

[nissanguy93]

Yea just found a small leak, looks to be coming from the top of the tank somewhere. Ill check it out tomorrow when i can get it up on a lift. Still not sure how its running 15 psi

[VegasDrifterS13]

Yea just found a small leak, looks to be coming from the top of the tank somewhere. Ill check it out tomorrow when i can get it up on a lift. Still not sure how its running 15 psi

If its at 15psi and was never adjusted by a Boost Controller, you have an Actuator/wastegate problem.

Sent from my SGH-T989 using Tapatalk 2

[Mikester]

First- get rid of the SAFC. This could very easily be the problem (in addition to fuel leak). Those things are garbage- Not to mention that NOTHING should ever be spliced into your main engine harness.

Second, your fuel system is very simple... Fuel coming from the top of the tank means that most likely, either your pump feed or pump return lines are leaking. It's 5/16" line and relatively easy to replace. This type of hose is about a buck per foot at Vatozone & you will only need about 3 feet.

Also, pull your pump and take a good look at it. Sometimes, the filter sock falls off causing crap to get into the pump & lines. Once you pull the pump, you will need to replace the big o-ring... they are like 5 bucks at any Nissan dealer- they usually have them on hand. As soon as you pull the fuel pump access panel, the o-ring expands & needs to be replaced. Without it, fuel will slosh out of the top of the tank; and the fuel smell would be MUCH worse.

...and like stated above, check your wastegate actuator... If it's adjustable, it's set too tight (looser actuator = less boost). A proper boost controller [electronic] will solve this for you permanently.

[nissanguy93]

Okay, removed the safc. I checked for fuel leak in the lines and they all look dry. I can see 2 wet spots from underneath on the top of the tank, like from under the foam padding between the tank and chassis. Would that be a leak in the tank itself or is there somewhere else to they leak from? Not dripping or anything just see wet spots and smell like gas. Maybe a leak it messing with fuel pressure and causing it to run poopy? Lol removing safc didnt fix the cutting out. Thanks guys

[Mikester]

Okay, removed the safc. I checked for fuel leak in the lines and they all look dry. I can see 2 wet spots from underneath on the top of the tank, like from under the foam padding between the tank and chassis. Would that be a leak in the tank itself or is there somewhere else to they leak from? Not dripping or anything just see wet spots and smell like gas. Maybe a leak it messing with fuel pressure and causing it to run poopy? Lol removing safc didnt fix the cutting out. Thanks guys

The pump feed/return hoses run from the top of the tank to the aft hardlines. Pop the fuel pump cover & take a look at the top of the tank, fuel pump etc while you're at it. You'll probably easily see where the leak is...

[nissanguy93]

Yea that's what i did and looked at all the lines top and bottom and they were dry. Think the tank itself may have a leak somewhere

[ultimateirving]

After driving for a few minutes, if you pull over and open the gas fill cap, does it sound like pressure escaping? can you hear air moving?

[nissanguy93]

Ill check, i know when i get gas theres no pressure release when i open the cap

[nissanguy93]

Did a test today and i have low fuel pressure. Only 33 at idleand 40 under load...hmmm

[nissanguy93]

Update: put a fuel pump and fpr in and seems to be running alot better. Pulling smooth just has a small hick up shifting into 2nd at low rpms but then picks right back up. Any ideas?