dkicker10

Hey everyone, I'll try to keep this as short as possible. I searched for a couple days and have found some direction as to how I should go about fixing it, but also am experiencing some issues that are really throwing me off. Here's the story.

Prepped the car all week for a drifting event. (KA24DET with supporting mods) Car ran great, zero hiccups. As I come up a hill on RT80, car does some brief fuel cut bullshit, but immediately returned to normal. As I'm coming back down the hill and getting back on throttle, the car wouldn't rev past 3K (limp mode) regardless of how much throttle I give it. So I limp it the mile to Pocono Raceway, the whole time the car is sputtering like all hell, wideband pegged at 10, black smoke (unburnt fuel) pissing out the exhaust, car jerking and bucking like crazy.

So of course I do the immediate visual inspection (hoses, clamps, anything obviously out of place) Everything checks out. Based on the symptoms mentioned, I'm thinking possible mass air flow issue (MAF), which would explain it running shitty and super rich. Upon further inspection, I notice my fuel pressure regulator (FPR) had dropped from 40 to like 8-10psi. So I'm thinking perhaps the fuel pump took a shit.

But the more I thought about it, things weren't adding up. If it were the MAF that broke, it should have no correlation to the FPR as the FPR is a mechanical device and thus not controlled by the computer. But if it was the fuel pump, or any fuel related issue causing the pressure to drop, then my wideband should have been pegged lean, not rich (pegged at 10 at idle)

I never did get it started again and had to get it towed home. I'm really just baffled as to what happened, and where to begin to fix it.

Could multiple things have broke simultaneously? Did something break and immediately cause something else to fail? Nothing seems to be adding up to me unless I'm overlooking or not understanding something correctly.

So far my list of potential culprits include:

Fuel Pump (its a wally 255)
Injectors - leaky or stuck open (550cc I believe)
MAF sensor - it's a Z32
TPS sensor - stock I think

Any help on this would be greatly appreciated!

Derek

dkicker10

UPDATE:

Swapped the MAF with a new one. Verified the TPS sensor is working correctly. Car still won't start. Pulled a small metal cap (from the top of the fuel pump itself) that was stuck inside the fuel pump housing hose. Thought for sure this was the issue, but the car still wont start. I tried to start it about 4-5 times and nothing.

Both of these changes have raised the fuel pressure to 20 psi (previously 8-10), per my gauge, when trying to crank the car over.

Am I over sighting something simple? Nothing is making sense and I don't even know what to try next!

Feeling frustrated...

tuzzio

The fact it went very rich, to me would point me toward an ignition issue.

Did you check for spark? Start there. Trace backwards.

dkicker10

thank you! I will try this and report back.

dkicker10

UPDATE! ok, so here's where I'm at now. Not getting spark! started checking for broken wires and correct voltage at the ignition source, since it definitely has fuel. Turns out there was a small exposure on a couple of the wires on the main harness. Voltage was at 14 and change at the exposure. Traced them back and they lead right to the relay that sits right before my MSD blaster ignition. Checked voltage at the ignition and it was like .6 or so. Which tells me the issue is between those two points, and thus, not sending enough power to cause the wires/plugs to work.

We narrowed it down to roughly six inches from the ignition, which includes this relay piece, and are pretty sure that is the issue. But I can't find the correct relay anywhere to simply replace it.

My idea to fix this is to wire up a switch panel for the ignition and starter (also the fuel pump, acc, ecu and fans). I believe this would bypass the ignition relay, and give me the ability to send constant power to the ignition, or no power at all, rather than depend on the relay to complete the circuit upon cycling the key through the "acc, on, start" positions.


First, will this even work or am I just being stupid? lol

If this will work, is it safe to bypass this relay on the ignition and send full power to the ignition, as long as I remember to turn it off

If this won't work, does anyone have experience or advice on making this work? In my head it makes sense, but the electrical system on a car is something I still have quite a bit to learn about.

Thanks for any feedback!

dkicker10

I didn't want to start a new thread, so I'm hoping someone can help me out.

I'm not getting enough power to the ignition. As mentioned earlier in the thread, I've got 14 volts leading up to what I believe is an "ignition relay", and .6 after. But to be honest, I'm not sure what it's called or why its important. I've included a picture to better illustrate the issue. Link at bottom.

- Can someone please explain to me what the item circled in red is called?
- What is its relevance to starting the car?
- Can I bypass (remove) it?
- Will there be any negative consequences to removing it?

I'm pretty sure whatever that mystery thing (circled in red) is called is whats causing the issues. As far as I can tell, this only serves as an anti-theft feature in the sense that is prevents sending power to the ignition unless the key is cycled to the "ON" position, which would complete the circuit and send the power to the ignition.

https://ibb.co/MCmbLT7

chieu

http://zilvia.net/f/showthread.php?t=169093

GOOGLE:
Basically the function of a condenser in a coil ignition circuit is to reduce the spark at the contact points as they open in the distributor and thus minimise burning and pitting of the points. Arcing is caused by the effect of self induction in the coil as the points interrupt the flow of current.

Not sure on how to bypass or if you should.

https://www.ebay.com/itm/Genuine-Nis...-/152433709718

dkicker10

Hey man, appreciate the feedback! this was all very helpful. I have some local Nissan techs working on tracking down a factory condenser unit