Another Weird SR Problem thread

[xoxide]

Ok guys im stumped on this one...

First, my setup-
Redtop SR (blacktop head)
Stock turbo, FMIC, HKS SQV bov
Walbro 255
NGK BKR7E plugs gapped .030
300zx fuel filter


I just finished the swap a month or so ago, and took it around the block- drives perfect.

Went to an event and had some weird issues..

When going into a turn (the track had a long straight into a large sweeper), the car pulled great and ran perfect. As soon as I threw the car sideways (in second and third), it would start cutting out pretty bad (to where I couldnt really hold a slide)... So once I got through the sweeper into the smaller part of the course I downshifted to first, and could slide the course in first.

First gear cut out just a little bit, but second and third cut out so bad I couldnt even slide really. The weird part is it ONLY cuts out while sideways. Even just in a normal spirited turn it doesnt cut out, just while drifting...

Im lost as to what it could be, ive tried:
Stock ECU (I have a tuned ECU that I believe is for 4 bar fuel pressure but I ran stock fuel pressure)... Stock ECU didnt change anything.
New MAF- Didnt do anything
Check engine harness for cut wires- nothing
Checked engine grounds- everything good
Checked to make sure fuel pump didnt fall off the bracket- was still fine



I do have my fuel pump relay bridged- could that be the issue?

Any other ideas? Im just lost.

[di-devol]

Something has to be shifting when you're swing the car around. Battery tie-down holding? Anything loose at all? I had my battery move just enough to cause problems on the track once.

How much gas did you have?

[xoxide]

Battery is in a steel battery box with aluminum tiedown.. Its not moving. I also tried a new battery which did not help.

Tank was over 3/4 full.

[di-devol]

Does the car back fire when it cuts out? Does it feel/sound like ign or fuel cutting I mean.

[xoxide]

No, no back fires. Im not really sure how to tell the difference between fuel/ignition cut-

When I threw it sideways I was in the high-ish revs, and it felt like the revs would drop super low, then come back up, then drop super low, then come back up. Not like the car was cutting completely off and coming back on.

[lightsource]

Does it matter which direction you slide? I think this may help find if the issue only occurs during a certain type of slide.

[xoxide]

Nope. Cuts out both ways.

Like I said, It cut out just a tiny tiny bit in first, but as soon as I tried to slide in second (in any direction), it cut out and kind of bucked if that makes any sense, so bad I couldnt hold a slide.

[Frank_Jaeger]

What kind of differential do you have?

What happens when you break traction on a launch?

[xoxide]

Welded. From the line it pulls just fine. Spins tires first/second down the straight without the cutting out. It only cuts out when its put sideways. The only thing I can think is something fuel/electrical related.

Ive done boost/vacuum leak tests and there is nothing leaking (little tiny leak from the T fittings but I cant imagine that causing this much trouble.

[jr_ss]

Sounds like you have a loose electrical connection somewhere and when you stress it either way youre having issues. I'd go over all your electrical connections. Check your MAF plug as well, Nissan MAF's have been known to have loose contacts making the car go full rich and kill power.

[xoxide]

Sounds like you have a loose electrical connection somewhere and when you stress it either way youre having issues. I'd go over all your electrical connections. Check your MAF plug as well, Nissan MAF's have been known to have loose contacts making the car go full rich and kill power.
I pulled the engine harness out saturday and checked over everything. No wires were cut, loose, etc. The MAF plug doesnt "clip" into the maf, it just stays on there with a little friction, but I ziptied it at the track to make sure that wasnt the issue.

I did simplify the harness (chassis), but I didnt cut ANY wires related to the fuel pump...

[Jack Bauer S14]

You could check if there is a loose ground somewhere... Or maybe even the fuel pressure regulator. Have you checked how many psi's it's throwing?

Sent from my XT910 using Tapatalk 2

[240boi115]

you might have a bummed fuel pump or check all your fuel lines...maybe one is messed up and shifts from under your car when getting sideways?

[ultimateirving]

Also did you check the harness in the drivers side fenderwell?

[xoxide]

Going to triple check grounds again tommorow. I dont have a fuel pressure gauge, but im going to get order one this week. I have no idea how old or how long the fuel pump sat for so I may end up just replacing that anyways.

Ultimateirving- There are no wires in my fender. I relocated the fusebox/fender harness to under my dash.

[KoukiMonsta]

I like the idea of replacing fuel pump and getting a gauge.

Edit. Get gauge. Decide then lol

[fliprayzin240sx]

This is an S14 right? My stab is the fuel pump holder came off the slot in the fuel tank and is flapping around inside your tank. I've done this shit on my Silvia in Japan. Shit would pop off and I'd watch my fuel pressure drop mid drift. I'd have to open up the cover and I'd have to slide the holder back in place.

[xoxide]

Hmm.. good info flip, I'll have to drain the tank some (still 3/4 tank haha, and check into that.