r32 gtr problem after racing.

[mistercrow]

Hey guys, last night i went lapping and a sudden problem up.

Heres what happened.

I went for two 20 minute sessions, and the track i race on mostly turns left. As i was racing when turning left my car started to jerk, sortof light misfire, but without gaz, like if no spark and no gaz, just nothing tjis happened while turning left all the lapping sessions. While racing in cold weather my power fc kept the egt light on for the last two laps, told myself ****, knocking is happening because of slight overboost (because of cold weather) so i finish my session and lower boost. Second session comes up, one lap into the sessions my car stalls, cranks but doesnt start, check pfc commander, nothing on, im like ****, ecu lost power. I get the car towed off the track and check under my hood, as i expected the eng cont fuse has blown, so i tell myself ill just switch fuses with the window fuse, but the fuse blows up. So obviously a short to ground, i will try to find that.

I tow my car home and on the towing ride my car obviously absorbed all the road hazards, well home after car was stored to repair, i put a new fuse in power window and pluged a test light in eng cont (turned on, duh!) the pfc turns on, but in the trunk, the green relay clicks on and off like crazy. I tested anotjer relay i had liying around and still clicks like crazy. What is that circuit? Anyone have any idea what the short could be? Where to look at first?

Thanks!

[nimblestix]

Attessa pump Or fuel pump I think?

sent from a galaxy far, far away

[Skym]

Check that the fuel pump wasn't run dry due to fuel starvation when cornering, which would explain the engine knocking, engine stalling (due to running lean).

Run a Sard or similar collector tank in the trunk with a new stock GTR fuel pump (or similar) as a lift pump from the stock fuel tank to the collector tank to prevent this from happening in the future and keep stock fuel tank near full.

Sard collector tank -

http://www.sard.co.jp/after_eng/products/engine/collector/collector.html

Also check wiring to fuel pump (might need to hardwire the fuel pump) with a Tomei fuel pump hardwire kit or this kit -

http://www.deatschwerks.com/products/accessories/fuel-pump-hardwire-installation-kit-detail

Best to run new wiring. If run more voltage, I think a higher amp fuel pump fuse is needed.

[mistercrow]

I already have a rewire to fuel pump done, and racing co ditions were full tank no surge tank though. i will check the rewire for a short to ground maybe? Because at the track relay wasnt clicking on off all the time while ecu was "off"

[Skym]

Relays do fail.

Check that you are using good quality connectors for the wiring.

[mistercrow]

update- went lapping today again.

as i got home from last monday, i put a new fuse in again and the car started and ran like a brand new car.
put a light in the place a fuse and shook all the wired from the car , where i could acces, and made sure no short to ground could be found. nothing.

only thing i found was a loose nut on starter (bendix to solenoid) thats it. tight it and tell myself that could be it.

tonight i go race, get on the track do 2 -3 laps everything is fine, then it starts again. as im turning left, the car misfire/backfires, everything turns off, the egt light comes on, and on the djetro controller the controller goes on and off, and when its off the cars runs bad. the eng control fuse didnt blow tonight, as it did last event.

at the track when the car was hot and the problem seemed to be there, i played with all the wiring and got nothing out of it.

any ideas? i know the fuel pump works all the time and the gaz tank was full.

[mistercrow]

Update. Yesterday i played with the car a bit, i unplugged the eng cont fuse under hood and the ecu doesnt turn off, what does the eng cont fuse control? And where does it go?

Second of all im running a map sensor power fc and my old wires from the mafs were melted. So probably grounding itself on the turbos or engine, i tried to simulate grounding the maf sensor but it doesnt create the problem.

[bobbo]

have you checked the harnesses that plug into the ecu? I've heard of guys having issues with them coming loose

[bizzle]

I had similar issue before when the car got pretty hot but I was still on factory AFMs/Power-FC. I ended up re-soldering both AFMs and the issue went away. How old is your P-FC? I'm wondering if the ECU capacitors are beginning to fail.

[mistercrow]

I am not running afm as it is a power fc djetro. Although the afm connectors are still there and i have found a melted afm connector, probably om turbos. I tried creating a short on it but no cigar. I still dont know why the eng cont under the hood fuse blew, and ecu wouldnt turn on, as without any fuse the ecu stays on.

[Skym]

Fuses usually blow when there's a bad earth or too much voltage / amps (could be related to the fuel pump hardwire being done incorrectly).

Check the earths on that circuit, especially into stock ECU plug (sometimes wires fall out of the plug or the plug is not seated correctly, could have a bent ECU plug).

[mistercrow]

What pin number would be the ecu ground?

[Skym]

Not sure which pinout without looking at wiring diagram. Ground is usually a black wire.

Sometimes if you ground it incorrectly to the wrong ground (ECU or chassis itself) it can cause weird problems or damage the device that you are grounding. More so with turbo timers.