KA Problems - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

nrmskate · 12-11-2009, 03:36 PM

Well, I just did my SOHC to DOHC swap, everything is complete, (Except power steering) and I have a problem. Whenever I start the car, it will run fine for about 10-13seconds then it will just die. Im running a AutoECU on a 5spd engine/tranny. I removed the thing that sends the exhaust fumes to the charcoal canister, im not sure if that could be the culprit.

Any insight?

racepar1 · 12-11-2009, 03:48 PM

Why does it die??? Does it lose spark, fuel pressure, or injector pulse??? You need a spark tester, a noid light, and a fuel pressure guage hooked up to the car for anyone to even try to diagnose that over the internet. I think it is likely a problem with your motorset, not your wiring or anything. One question though, why in the hell did you disconnect the charcoal canister???

I guess to start you could try to check for vacuum leaks as well. Just get a can a carb cleaner and spray it around the intake and vacuum hoses while the engine ie running. If you have a vacuum leak the idle will change when it sucks in the carb cleaner.

nrmskate · 12-11-2009, 11:20 PM

I did not disconnect the charcoal canister.

Sorry, im confusing people.

You know how there is EGR tube, O2 sensor, and another metal tube that comes out of the exhaust manifold? I removed that because I had to saw it off to get the motor in the car. It look like it went from Exhaust Manifold > Header. I will take pics and a video soon.

Get spark, gets fuel, gets air. Timing is perfect. I do have one vacuum line open as I have no idea where it goes, it's a long one with white on both ends?

240sxvaj · 12-11-2009, 11:39 PM

Quote:

Originally Posted by nrmskate

I did not disconnect the charcoal canister.

I do have one vacuum line open as I have no idea where it goes, it's a long one with white on both ends?

It probably goes to your canister. plug it and you should be fine. There isnt anything wrong with disconnecting the charcoal canister as long as you plug all the vacuum lines just remember never leave any vacc lines open. I had a similiar problem where my car would die at some point found out i forgot to plug one of those long vacuum lines coming from the intake mani.

nrmskate · 12-11-2009, 11:45 PM

Well, I found out the thing I removed was the PAIR Valve (AIV).

Which, is common and shouldn't effect anything.

It says in the FSM that there should be one vacuum line that is atmospheric, which I have.

I think I may know my problem, tell me if this sounds right.

The AIV was used to due something that kept your car idling.

But now that it's removed, people have been saying that I need to adjust my throttle cable open a little so it can idle on its own now.

That's the best way I can explain it, doesn't sound very good, but it's not easy to explain.

240sxvaj · 12-12-2009, 12:16 AM

Quote:

Originally Posted by nrmskate

Well, I found out the thing I removed was the PAIR Valve (AIV).

Which, is common and shouldn't effect anything.

It says in the FSM that there should be one vacuum line that is atmospheric, which I have.

I think I may know my problem, tell me if this sounds right.

The AIV was used to due something that kept your car idling.

But now that it's removed, people have been saying that I need to adjust my throttle cable open a little so it can idle on its own now.

That's the best way I can explain it, doesn't sound very good, but it's not easy to explain.

From what i remember when i took my PAIR vavle off for turbo it didnt effect the idle of the car. At the moment i'm back to N/A with deleted EGR/canister/Pair valve and no problem whatsoever. As long as you know which line it is then probably it's something else....hows your rpm idle sitting at? if its a little low then turn it up a bit and see if that helps.

nrmskate · 12-12-2009, 07:20 PM

That's the thing, it will idle at 1500 rpms at start because, thats what cars do when they first start up. But, I did find out today that I can keep the car alive ive I mess with the throttle, I don't have a throttle cable hooked up since ive yet to order a DOHC Throttle cable.

12-11-2009, 03:36 PM	#1
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 979 Trader Rating: (9) Feedback Score: 9 reviews	KA Problems Well, I just did my SOHC to DOHC swap, everything is complete, (Except power steering) and I have a problem. Whenever I start the car, it will run fine for about 10-13seconds then it will just die. Im running a AutoECU on a 5spd engine/tranny. I removed the thing that sends the exhaust fumes to the charcoal canister, im not sure if that could be the culprit. Any insight?

12-11-2009, 03:48 PM	#2
racepar1 Post Whore! Join Date: Jul 2007 Location: Simi Valley, CA Age: 42 Posts: 9,006 Trader Rating: (106) Rides Gallery: racepar1 Feedback Score: 106 reviews	Why does it die??? Does it lose spark, fuel pressure, or injector pulse??? You need a spark tester, a noid light, and a fuel pressure guage hooked up to the car for anyone to even try to diagnose that over the internet. I think it is likely a problem with your motorset, not your wiring or anything. One question though, why in the hell did you disconnect the charcoal canister??? I guess to start you could try to check for vacuum leaks as well. Just get a can a carb cleaner and spray it around the intake and vacuum hoses while the engine ie running. If you have a vacuum leak the idle will change when it sucks in the carb cleaner.

12-11-2009, 11:20 PM	#3
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 979 Trader Rating: (9) Feedback Score: 9 reviews	I did not disconnect the charcoal canister. Sorry, im confusing people. You know how there is EGR tube, O2 sensor, and another metal tube that comes out of the exhaust manifold? I removed that because I had to saw it off to get the motor in the car. It look like it went from Exhaust Manifold > Header. I will take pics and a video soon. Get spark, gets fuel, gets air. Timing is perfect. I do have one vacuum line open as I have no idea where it goes, it's a long one with white on both ends?

12-11-2009, 11:45 PM	#5
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 979 Trader Rating: (9) Feedback Score: 9 reviews	Well, I found out the thing I removed was the PAIR Valve (AIV). Which, is common and shouldn't effect anything. It says in the FSM that there should be one vacuum line that is atmospheric, which I have. I think I may know my problem, tell me if this sounds right. The AIV was used to due something that kept your car idling. But now that it's removed, people have been saying that I need to adjust my throttle cable open a little so it can idle on its own now. That's the best way I can explain it, doesn't sound very good, but it's not easy to explain.

12-12-2009, 07:20 PM	#7
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 979 Trader Rating: (9) Feedback Score: 9 reviews	That's the thing, it will idle at 1500 rpms at start because, thats what cars do when they first start up. But, I did find out today that I can keep the car alive ive I mess with the throttle, I don't have a throttle cable hooked up since ive yet to order a DOHC Throttle cable.