Engine Dying - HELP - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

2.5T_/<ouki · 02-05-2013, 06:18 PM

*** ATTENTION: This is NOT due to my BoV being vented to atmosphere. As i have ran my BoV vented for 2 years straight without this issue. This is an RB25 Series 1.

1 out of every 60 times when coming to a stop or even slowing down to get into the driveway my RB25 will drop revs to the point of the engine shutting off. I do NOT step on the pedal and always drive like a granny so I know for a fact it's not a boosting and then venting to atmosphere problem as my BoV hardly opens at the RPM's i drive.

Recently I purchased a 3" Aluminum pipe w/ a 45* angle to use on the turbo inlet instead of the accordion looking stock pipe. In doing so, i had to extend the MAF wires about a foot to reach the new MAF location. (2) of the MAF wires were shielded and twisted together (White & Orange). I however did not shield the 1 foot extension so i thought this was the problem. I have since then shield those wires; I wrapped the wires in foil and then twisted about 6 strands of thin metal wire around the foil/wires the entire length of the extension, and then soldered a peace of wire to the 6 strands to act as a ground and then grounded it to the firewall however the problem persists. I was thinking that the MAF was getting EFI interference and maybe shutting itself off and then the ECU not seeing a MAF signal, however i have ConZult ECU program to monitor all my settings and the MAF votage was still present when the engine dies, however it was at 0.4v

Today i figured out that i can make it stall every single time when going up a hill. I put the car in 1st, drive up the hill until i hit about 2k RPM and then completely let off the gas while holding the clutch in. Sure enough, the RPM's drop all the way to 0 and engine shuts off.

This problem did not start until i changed the turbo inlet pipe and extended the MAF wires.

Timing
15* BTDC @ Idle w/ 650 RPM

TPS Voltage
0.45v @ Idle / 4.20v @ WOT

MAF Voltage
1.08v @ Idle

zerodameaon · 02-05-2013, 06:42 PM

Take off the extension and put the old inlet pipe back on and see if the issue goes away, if it does then that was your problem. If that does not change anything get a new MAF the one in your picture looks like it has been opened, moisture could have gotten in it and started causing issues.

2.5T_/<ouki · 02-05-2013, 06:43 PM

Quote:

Originally Posted by zerodameaon

Take off the extension and put the old inlet pipe back on and see if the issue goes away, if it does then that was your problem. If that does not change anything get a new MAF the one in your picture looks like it has been opened, moisture could have gotten in it and started causing issues.

You are correct, my MAF has been opened. I had to open it up to resolder the plug to the MAF. I had a problem with the car cutting out a while back and i fixed the issue by soldering it. So i opened it up again recently when experiencing this new problem to make sure the solder points were still good.

OrangeVirus1 · 02-05-2013, 06:48 PM

maybe when you extended the maf wires you mixed one of them up

2.5T_/<ouki · 02-05-2013, 07:15 PM

Quote:

Originally Posted by OrangeVirus1

maybe when you extended the maf wires you mixed one of them up

No i have quadruple checked it. The engine runs great and doesn't stall except for a few times I come to a stop.

zerodameaon · 02-05-2013, 11:55 PM

Change back to the other inlet pipe and see if the issue goes away. You can leave the extension on for that.

2.5T_/<ouki · 02-05-2013, 11:58 PM

Quote:

Originally Posted by zerodameaon

Change back to the other inlet pipe and see if the issue goes away. You can leave the extension on for that.

I'm going to try it, but why would just adding this pip cause that to happen? I just don't understand lol. If anything, i would think it would have improved things as my inlet pipe was capped off with a milk bottle top and a screw ROFL. Those were plugging the breather holes.

I found a dude on CL selling a J60 MAF for real cheap so i went ahead and purchased it JUST in case.

2.5T_/<ouki · 02-06-2013, 03:53 PM

UPDATE: Today I put back on the stock accordion turbo inlet pipe and I could not make the engine stall once. I then went back home and put back on the new 3" turbo inlet pipe and sure enough the engine will stall here and there when coming to a stop or slowing down.

Could this be due to the turbo not sucking hard enough to get all of the air that was just metered? I'm kind of at a loss here. I wouldn't have thought a pipe like this wouldnt be a problem but rather "fixed" my stock turbo inlet pipe as its being plugged with a milk carton cap and a screw LOL.....

My tune appointment was for this Saturday so this is the reason for "fixing" my turbo inlet pipe.

zerodameaon · 02-06-2013, 04:24 PM

So maybe it could be due to the BOV, for shits and giggles try setting it up as recirc and see if the issue goes away with the new one. I don't know the mechanics of the air and why it could cause it but I have seen the inlet change do this on a few turbo engines.

2.5T_/<ouki · 02-06-2013, 04:26 PM

Quote:

Originally Posted by zerodameaon

So maybe it could be due to the BOV, for shits and giggles try setting it up as recirc and see if the issue goes away with the new one. I don't know the mechanics of the air and why it could cause it but I have seen the inlet change do this on a few turbo engines.

No way to rig it up, but 100% sure it's not due to the BOV. My BOV doesnt even open under the speeds/RPM that I'm driving in so i know it's not a "loss" of air.

Appreciate your response.

zerodameaon · 02-07-2013, 04:01 PM

I forgot about the not opening part.

2.5T_/<ouki · 02-07-2013, 04:15 PM

So i figured out it's due to "reversion" causing my voltages in my MAF to go haywire shutting it down.

Looks i will be going blow through setup now.

feito · 02-07-2013, 09:05 PM

happened to me when i upgraded my stock intake pipe, except i upgraded to one of those silicone ones. What u can do is recirculate your bov and adjust it. I am recirculated and it stopped after a few adjustments. Your vented bov might have been causing it to run rough/rich already, that plus the added extra flow provided by the new intake pipe may be the cause of your problem. I wouldnt go blow through.

2.5T_/<ouki · 02-07-2013, 09:54 PM

Quote:

Originally Posted by feito

happened to me when i upgraded my stock intake pipe, except i upgraded to one of those silicone ones. What u can do is recirculate your bov and adjust it. I am recirculated and it stopped after a few adjustments. Your vented bov might have been causing it to run rough/rich already, that plus the added extra flow provided by the new intake pipe may be the cause of your problem. I wouldnt go blow through.

My BOV is a bit too far to recirculate back to the Intake pipe. This would mean running a 4-5' hose across my engine bay which would look ghetto as hell and may not even fit anywhere in the bay as its pretty crammed as it is.. I can possibly mount the BOV on the hotpipe side and run a shorter tube but might not be as effective.

Why wouldn't you personally go blow through? I've heard nothing but good things about it. Seems like it has more advantages than a draw trough.

02-05-2013, 06:18 PM	#1
2.5T_/<ouki Zilvia FREAK! Join Date: Oct 2011 Location: SoCal Posts: 1,150 Trader Rating: (13) Feedback Score: 13 reviews	Engine Dying - HELP *** ATTENTION: This is NOT due to my BoV being vented to atmosphere. As i have ran my BoV vented for 2 years straight without this issue. This is an RB25 Series 1. 1 out of every 60 times when coming to a stop or even slowing down to get into the driveway my RB25 will drop revs to the point of the engine shutting off. I do NOT step on the pedal and always drive like a granny so I know for a fact it's not a boosting and then venting to atmosphere problem as my BoV hardly opens at the RPM's i drive. Recently I purchased a 3" Aluminum pipe w/ a 45* angle to use on the turbo inlet instead of the accordion looking stock pipe. In doing so, i had to extend the MAF wires about a foot to reach the new MAF location. (2) of the MAF wires were shielded and twisted together (White & Orange). I however did not shield the 1 foot extension so i thought this was the problem. I have since then shield those wires; I wrapped the wires in foil and then twisted about 6 strands of thin metal wire around the foil/wires the entire length of the extension, and then soldered a peace of wire to the 6 strands to act as a ground and then grounded it to the firewall however the problem persists. I was thinking that the MAF was getting EFI interference and maybe shutting itself off and then the ECU not seeing a MAF signal, however i have ConZult ECU program to monitor all my settings and the MAF votage was still present when the engine dies, however it was at 0.4v Today i figured out that i can make it stall every single time when going up a hill. I put the car in 1st, drive up the hill until i hit about 2k RPM and then completely let off the gas while holding the clutch in. Sure enough, the RPM's drop all the way to 0 and engine shuts off. This problem did not start until i changed the turbo inlet pipe and extended the MAF wires. Timing 15* BTDC @ Idle w/ 650 RPM TPS Voltage 0.45v @ Idle / 4.20v @ WOT MAF Voltage 1.08v @ Idle Last edited by 2.5T_/<ouki; 02-18-2020 at 02:20 PM..

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02-05-2013, 06:48 PM	#4
OrangeVirus1 BANNED Join Date: Jan 2013 Location: PyongYang DPRK-N. Korea, Province 2 Posts: 1,236 Trader Rating: (0) Feedback Score: 0 reviews	maybe when you extended the maf wires you mixed one of them up

02-06-2013, 03:53 PM	#8
2.5T_/<ouki Zilvia FREAK! Join Date: Oct 2011 Location: SoCal Posts: 1,150 Trader Rating: (13) Feedback Score: 13 reviews	UPDATE: Today I put back on the stock accordion turbo inlet pipe and I could not make the engine stall once. I then went back home and put back on the new 3" turbo inlet pipe and sure enough the engine will stall here and there when coming to a stop or slowing down. Could this be due to the turbo not sucking hard enough to get all of the air that was just metered? I'm kind of at a loss here. I wouldn't have thought a pipe like this wouldnt be a problem but rather "fixed" my stock turbo inlet pipe as its being plugged with a milk carton cap and a screw LOL..... My tune appointment was for this Saturday so this is the reason for "fixing" my turbo inlet pipe.

02-07-2013, 04:15 PM	#12
2.5T_/<ouki Zilvia FREAK! Join Date: Oct 2011 Location: SoCal Posts: 1,150 Trader Rating: (13) Feedback Score: 13 reviews	So i figured out it's due to "reversion" causing my voltages in my MAF to go haywire shutting it down. Looks i will be going blow through setup now.

02-07-2013, 09:05 PM	#13
feito Nissanaholic! Join Date: May 2007 Location: Texas Posts: 1,999 Trader Rating: (1) Feedback Score: 1 reviews	happened to me when i upgraded my stock intake pipe, except i upgraded to one of those silicone ones. What u can do is recirculate your bov and adjust it. I am recirculated and it stopped after a few adjustments. Your vented bov might have been causing it to run rough/rich already, that plus the added extra flow provided by the new intake pipe may be the cause of your problem. I wouldnt go blow through.