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bmaddock · 07-24-2014, 06:15 AM

Install Diary:
Day 1:

I had issues installing the turbo manifold as the exhaust studs hit the manifold's turbo flange. I had to cut the stud shorter. Also had the downpipe hitting a brake line coming off the brake master cylinder. To solve this I acquired an S14 5-speed, non-ABS brake booster as opposed to my S13 auto, non-ABS booster (yes my car is 5-speed swapped).

Day 2:

The largest problem I'm having is lack of idle right now. The engine will turn over but I'm forced to feather the throttle to keep it really alive. It will idle but sounds off in timing and barely holds it. I checked the resistance and continuity in all my injectors and they appear good (11 ohms). Hooked a timing light up to each spark plug wire and spark seems to be consistent. There is also some white smoke coming out of the downpipe (the extent of my exhaust right now) that could be oil but I think is indications of rich combustion.

I'm going to look more into this tomorrow but am curious if anyone has better suggestions. My main leads are possible vacuum leak, bad o2 sensor, off in timing (though I don't know how as it was never touched and ran fine NA), or leaky injector o-rings. It could also be an incorrect tune but can not rule that as an issue just yet. I've also considered crankcase ventilation as an issue because right now I have the stock (NA, OEM) PCV system in tact expect for the valve cover port is now in the turbo intake plumbing instead. Eventually I'd live to place the valve cover VTA and place the PCV valve in vacuum using the turbo intake pipe while blocking off the intake manifold but I don't think this should be an issue while just attempting to idle. I could be wrong, please correct me if so.

Day 3:

Fixed my crankcase vent earlier today and cleaned my MAF. Correctly routing the PCV so that it's in vacuum via the turbo intake, blocking off the vacuum tree into the manifold, and put a filter on the valve cover.

The car still starts right up but won't really idle. Seems rich (no wideband) and no smoke anymore. I got the car to idle eventually but it's less than 500 rpm. I then tried holding the engine at a certain speed but it would slowly bog down and try to stall out. I'm going to post up my vacuum diagram later but don't forsee any issues. Suggestions are appreciated.

Day 4:

Took some time and cleaned MAF connection, still ran about the same. I then plugged IACV and ran slightly better but I still could not hold the engine at one speed. I pulled the dipstick out and faintly could smell gas...leading me to believe that my timing is off. Does anyone know what Martin (RS Enthalpy) sets timing to? I emailed him but I'm sure he's busy this week. Used tune is not the way to go, forgot about timing.

Day 5:

Car is running better. I replaced the O2 sensor, got new injector o-rings since mine were pretty loose fitting, and cleaned corroded MAF connections. It fires right up but seems to chop up, hesitate and stall out now. Below is a video of how it's running. I only see -15 at idle though so I'm certain of a vacuum leak but haven't actually looked since I noticed that tonight. I'll try some tomorrow. I fear my EGR block plate isn't sealing well enough. I also noticed a sizeable exhaust leak I'm looking to plug up tomorrow. I'm sure this doesn't help me out with even more skewed O2 readings causing rich conditions.

Watch at 0:14 when I hold the gas pedal at the 2000RPM position yet the motor chokes and stalls (too much fuel?)
[video=youtube_share;yQSm-seLbtA]http://youtu.be/yQSm-seLbtA[/video]

Day 6:

Took me a while to do the obvious but finally checked codes and got code 34, knock sensor. I should have checked this before hand but after plugging up all exhaust leaks and any potential vacuum leaks I was fed up and sent the ECU to my tuner. He found potentially loose connections and is fixing those while I prepare for starting it up. Despite Martin's awesome response time, it's still taken close to 2 weeks to ship, fix, and now return the ECU to me. Hopefully coming in tonight, then I'll try starting the car again.

If it idles bad still, I will then pursue code 34, knock sensor. For tesitng and validation I will likely do the resistor trick to relieve the ECU of the code. From my understanding, code 34 moves the timing map into a protective secondary where timing is extremely conservative to save the motor. I have a feeling this is my problem as it's common for KA's knock sensor subharness to short out and cause these issues. This has been a great learning experience, reminding me to always check the small things and not to forget them.

Day 7:

After diagnosing for nearly a week straight, then narrowing it down to a control issue, it turned out to be the ECU. Took a while between shipping to FL and receiving my repaired ECU, but it started right up and idled perfectly. -20 vacuum, solid idle.

I feel like you don't hear of this issue very often but be weary of used ECUs and potentially broken connections. Martin (RS Enthalpy) sent me this image, indicating two areas of concern when checking your ECU's condition. My bad connection is on the right.
High Res: http://i.imgur.com/dbDZzHm.jpg

I also cheated and used the resistor trick to rid my car of the knock sensor code but this is a bad idea. I'm currently waiting on my new knock sensor subharness to come in so that I can reissue my knock sensor.

One Month Later:
Tune is slightly lean, sent to RS Enthalpy to revise for richer in-boost conditions.

Two Months Later:
Still battling exhaust leaks. If you hear a ticking noise when under load but not easily heard off throttle..it's likely an exhaust manifold leak. I had some issues with manifold gaskets and did a temporary, ghetto fix using copper RTV. It's ugly but will have to do for now. Basically I looked up the Emusa top mount manifold and some of the earlier designs had horrible ports. Not only were they not port matched to the head but they were drilled off center. Haven't had the time to address this just yet.

Four Months Later:
Blew out my paper T3 gasket, now using OEM Nissan 300ZX metal T3 gasket (Nissan Part #: 14415-4P200). Also using sprayable copper gasket on all of those flanges too so that I can stop them all up.

07-24-2014, 06:15 AM	#3
bmaddock Zilvia Junkie Join Date: Sep 2011 Location: Richmond Posts: 506 Trader Rating: (1)	Install Diary: Day 1: I had issues installing the turbo manifold as the exhaust studs hit the manifold's turbo flange. I had to cut the stud shorter. Also had the downpipe hitting a brake line coming off the brake master cylinder. To solve this I acquired an S14 5-speed, non-ABS brake booster as opposed to my S13 auto, non-ABS booster (yes my car is 5-speed swapped). Day 2: The largest problem I'm having is lack of idle right now. The engine will turn over but I'm forced to feather the throttle to keep it really alive. It will idle but sounds off in timing and barely holds it. I checked the resistance and continuity in all my injectors and they appear good (11 ohms). Hooked a timing light up to each spark plug wire and spark seems to be consistent. There is also some white smoke coming out of the downpipe (the extent of my exhaust right now) that could be oil but I think is indications of rich combustion. I'm going to look more into this tomorrow but am curious if anyone has better suggestions. My main leads are possible vacuum leak, bad o2 sensor, off in timing (though I don't know how as it was never touched and ran fine NA), or leaky injector o-rings. It could also be an incorrect tune but can not rule that as an issue just yet. I've also considered crankcase ventilation as an issue because right now I have the stock (NA, OEM) PCV system in tact expect for the valve cover port is now in the turbo intake plumbing instead. Eventually I'd live to place the valve cover VTA and place the PCV valve in vacuum using the turbo intake pipe while blocking off the intake manifold but I don't think this should be an issue while just attempting to idle. I could be wrong, please correct me if so. Day 3: Fixed my crankcase vent earlier today and cleaned my MAF. Correctly routing the PCV so that it's in vacuum via the turbo intake, blocking off the vacuum tree into the manifold, and put a filter on the valve cover. The car still starts right up but won't really idle. Seems rich (no wideband) and no smoke anymore. I got the car to idle eventually but it's less than 500 rpm. I then tried holding the engine at a certain speed but it would slowly bog down and try to stall out. I'm going to post up my vacuum diagram later but don't forsee any issues. Suggestions are appreciated. Day 4: Took some time and cleaned MAF connection, still ran about the same. I then plugged IACV and ran slightly better but I still could not hold the engine at one speed. I pulled the dipstick out and faintly could smell gas...leading me to believe that my timing is off. Does anyone know what Martin (RS Enthalpy) sets timing to? I emailed him but I'm sure he's busy this week. Used tune is not the way to go, forgot about timing. Day 5: Car is running better. I replaced the O2 sensor, got new injector o-rings since mine were pretty loose fitting, and cleaned corroded MAF connections. It fires right up but seems to chop up, hesitate and stall out now. Below is a video of how it's running. I only see -15 at idle though so I'm certain of a vacuum leak but haven't actually looked since I noticed that tonight. I'll try some tomorrow. I fear my EGR block plate isn't sealing well enough. I also noticed a sizeable exhaust leak I'm looking to plug up tomorrow. I'm sure this doesn't help me out with even more skewed O2 readings causing rich conditions. Watch at 0:14 when I hold the gas pedal at the 2000RPM position yet the motor chokes and stalls (too much fuel?) [video=youtube_share;yQSm-seLbtA]http://youtu.be/yQSm-seLbtA[/video] Day 6: Took me a while to do the obvious but finally checked codes and got code 34, knock sensor. I should have checked this before hand but after plugging up all exhaust leaks and any potential vacuum leaks I was fed up and sent the ECU to my tuner. He found potentially loose connections and is fixing those while I prepare for starting it up. Despite Martin's awesome response time, it's still taken close to 2 weeks to ship, fix, and now return the ECU to me. Hopefully coming in tonight, then I'll try starting the car again. If it idles bad still, I will then pursue code 34, knock sensor. For tesitng and validation I will likely do the resistor trick to relieve the ECU of the code. From my understanding, code 34 moves the timing map into a protective secondary where timing is extremely conservative to save the motor. I have a feeling this is my problem as it's common for KA's knock sensor subharness to short out and cause these issues. This has been a great learning experience, reminding me to always check the small things and not to forget them. Day 7: After diagnosing for nearly a week straight, then narrowing it down to a control issue, it turned out to be the ECU. Took a while between shipping to FL and receiving my repaired ECU, but it started right up and idled perfectly. -20 vacuum, solid idle. I feel like you don't hear of this issue very often but be weary of used ECUs and potentially broken connections. Martin (RS Enthalpy) sent me this image, indicating two areas of concern when checking your ECU's condition. My bad connection is on the right. High Res: http://i.imgur.com/dbDZzHm.jpg I also cheated and used the resistor trick to rid my car of the knock sensor code but this is a bad idea. I'm currently waiting on my new knock sensor subharness to come in so that I can reissue my knock sensor. One Month Later: Tune is slightly lean, sent to RS Enthalpy to revise for richer in-boost conditions. Two Months Later: Still battling exhaust leaks. If you hear a ticking noise when under load but not easily heard off throttle..it's likely an exhaust manifold leak. I had some issues with manifold gaskets and did a temporary, ghetto fix using copper RTV. It's ugly but will have to do for now. Basically I looked up the Emusa top mount manifold and some of the earlier designs had horrible ports. Not only were they not port matched to the head but they were drilled off center. Haven't had the time to address this just yet. Four Months Later: Blew out my paper T3 gasket, now using OEM Nissan 300ZX metal T3 gasket (Nissan Part #: 14415-4P200). Also using sprayable copper gasket on all of those flanges too so that I can stop them all up. __________________ Last edited by bmaddock; 04-22-2015 at 07:44 AM..