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Discussion starter · #102 ·
Turns out my wheels didn't clear the fucking brakes. A larger rotor/brake setup would have actually fit better because of the spoke profile on the wheels, but whatever. Slapped some 8mm spacers on for about 2mm clearance and the lugs still seem to have a good amount of thread.





New Waterpump, thermostat and temp sensor installed. There was no thermostat, so I'm a little concerned why I was having overheating issues, but I'll make sure to bleed the system and hopefully it will be all good.

Hopefully I can take it around the block this weekend. Going to need some new tires here soon. Looking at Nitto Motivos, or Dunlop Direzza DS102s..
 
Scoot's probably best described as the human form of the 240sx FSM. Dude's one of your best, if not the best resource on this forum. Keep up the good work. And keep posting. Threads like these are the backbone of the community. Without members like you sharing builds with the good and the bad, forums would serve no real purpose.
 
Discussion starter · #105 ·
After doing the tension rods and the coilovers my shit was all outta whack and pulled heavy to one side so I took it to get an alignment. $160 and now it drives straight as an arrow. W/o camber adjustment in the rear there's not a lot that can be done about that. Probably my next purchase along with a new set of tires.

Really like how it's come along, nice interior, nice stereo, good power, brakes feel good and not too fucking bouncy. I'm done working on it for a while and just plan on cruising it, ripping it around and just enjoying it. I'll keep fucking with the tune for a while and maybe once all this covid shit is over I can take it in and hit a dyno next fall or something. I have been doing some video/movie editing and maybe I can get some good video clips and shit and put something together.

Turns out the temp sensor/switch for the fans died, not sure how or why. Put in a new one and fans are working again. Kicks on at 195, off at 185. Almost seems to low, because the dash temp gauge barely starts rising and the fans kick on and goes back down to cold. Need a way to verify the fans aren't running when cruising above 35mph.

I did seal up the windshield with some, uhm, roof patch shit. I thought it would smooth out, but it's basically tar that looks like dog shit. Should have just went with some black caulk, but it should be sealed up. It's going to be a nightmare getting it all out.:fonix:

 
That's pretty tiiiiiiiiiiiiiiiiight. I took too long to align my car because of some bad bushings/links so the alignment dudes told me to get that fixed first. By the time I could and went back the [new] tires had already conformed to the then-current alignment and now that it's aligned, not only does it pull right, but when I go left the tires get nice and loud and when I turn right, they are sooooooooooo quiet.

Keep them posts coming along, brah.
 
Discussion starter · #108 ·
Thanks guys! Still messing with the idle, I think it has to do with the AAC/IACV. One thing I noticed is that it pulls about ~17.3in/hg when it's cold, then it pulls around ~21in/hg once it warms up. I will run another idle log today.

Noticing some binding of the spring on the front right and heard a weird rubbing noise I need to look into also..

 
Discussion starter · #109 ·
Looked into the binding, turns out the spring perch was loose causing the spring to turn when cranking the wheel. All fixed. But I'm having problems with the freaking idle still. Here's the link to the Nismotronic Thread over on Zilvia.

Here's the Problem: From cold start up it will idle rough at 15-17 AFR at 17.5in/hg until it warms up, not to any specific temp, but at one point, like a light switch, the idle will smooth out except that it idles at 12.5 AFR and vacuum jumps to 20.6in/hg. And to make things more confusing once the electric fans kick on it idles perfect at 13.5-14.5 AFR, once they kick off goes back to 12.5 AFR.

I had a couple ideas but no real conclusion.

Blocked or sticking AAC/IACV valve, however adjusting the limits on the ECU does seem to change the idle, but does not help improve the situation. I did mess with the screw on the IACV a little bit and that changes the idle fairly drastically. Once it was all warmed up I adjusted it to Idle right around 975. I had no reason to adjust the throttle stop screw or anything like that.

Something with the tune or some parameter causing it to do this, but I cannot find anything. I checked the injector battery/voltage offset. Nismotronic has a preset for Nismo 740cc, that's what I'm using.

I've checked the base fuel pressure. 43psi with no vaccuum.

Could it be something mechanical? or electrical? or in the ECU? Or?

Ordered a BT dongle for the Nismotronic to run TunerView which has some sweet features. Looking to do some videos with gauge overlays! Stoked!
 
Discussion starter · #111 ·
Thanks man! No, I never did anything with the pickup. Didn't see a reason it would cause any problems.

Bluetooth dongle installed. It just plugs right into the board. Still working out the gauge layout/video shit, but seems pretty cool I just need a way to mount my phone for video.




Edit: Wondering if the idle shit is some sort of voltage issue? I hope I didn't suck something up the intake after putting everything together, but being intermittent or being weird when cold/warm like that wouldn't make a lot of sense.. Fack! Really that's the only issue I'm having.. Well that and this COVID shit..
 
https://zilvia.net/f/showthread.php?p=5980612

Page 3, post # 61 the guy talks about it. I can see both trains of thought on why it's good/bad to do it.

I'd personally just run the newer pickup (check this thread)

https://www.nicoclub.com/archives/sr20det-oil-strainerpickup-tube-replacement.html

If you really are going to be doing any kind of spirited driving, I'd do a baffled oil pan and just run the larger mouth pickup(no holes drilled into it).



The bluetooth dongle is used with a tablet so you can have a digital gauge setup right? That's pretty sweet.
 
Discussion starter · #114 · (Edited)
Good point on the oil pickup, but to add I am running an oversized baffled/trap door ISR oil pan.

I tried running some seafoam through the IACV, and I think all it did was make it smoke real bad and didn't really do anything..


Pulled the IM yesterday and will disassemble and clean it all up although it looks pretty clean. I might just buy a new IACV but goddamn they're expensive. I'll scope out the valves and check em out later today.

5/13/20 EDIT:
I tested the IACV with a meter and it all checked out. Everything was relatively clean but the only thing I noticed is that there was a pool of oil in my lower intake manifold. Probably due to not running a vac source on the other side, which has now been addressed. I cleaned it all up and will throw it back together and if I'm still having idle issues, I'll pull it all back out and buy a new IACV.


FYI, The dome light for a S13 hatchback with a sunroof is the exact same as the nissan hardbody pickup and a company in Thailand makes new ones. I bought mine from Amazon for $16.50.
 
Discussion starter · #115 · (Edited)
Welp. Tore it all down and put it all back together and no fucking luck. It's gotta be the IACV!? I would really, really, hate to buy one, put it in and it not fix my issue though..

And the socket for the plug on the hardbody light only needs slight trimming to get it to plug in. Not exactly the same I guess, but it does work..

Edit: Ordered a new IACV. $135 from Nissan race shop. I hope this does it...

Edit 2: NO response from nissan race shop for my order, which I will probably cancel, maybe they're closed for COVID or something? But I've got an idea. the IACV is composed of a 2 devices, the AAC (Auxiliary air control) and the FICD (fast idle control device) I believe my problem is not with the AAC as I have been able to adjust the AAC duty % through the nismotronic and it seems to affect the idle. I think * maybe* the FICD is malfunctioning and I don't have AC so I don't need it anyway.. I plan to try to disconnect the FICD and keep the AAC connected, but the kicker is that both are connected to one plug, but I have an idea to jumper the pins for the AAC and leave the FICD disconnected or possibly de-pin the socket for the FICD.
I should note (and may have mentioned before) that when the fans are on loading the engine a little bit more the idle is better..

Wish I had found this before as I didn't take the IACV apart. I may have been able to test the solenoid operation for the FICD. Doh!
https://www.nicoclub.com/archives/z32-tech-curing-erratic-idle-issues-part-1.html

Edit 3:
Well, that didn't do anything.
1.) Tried running w/o the FICD valve and only the AAC Valve. I was able to get it to idle around 13.8-14.5 AFR except I had to set the Min. AAC duty to around 50% and adjust the screw on the IACV all the way in which would only lower the idle to 1100 rpm. No Thanks.
2.) Put 12V to the FICD pins and heard audible click and tried while idling and it significantly raised the idle. Seems to work fine.
3.) Died a little bit inside.

I'm running out of ideas..

Symptoms again:
When cold it will idle at 15-16AFR pulling approx. 19.3 in/hg albiet a little rough. Not violently shaking, just a little bumpy.
When warm it will idle at 11.8-12.5 pulling appox. 20.8 in/hg smooth as butter. but trying to lean it out to 13.5-14.5 it misses and pops.
Somewhere between cold and warm the vacuum jumps from 19.3 to 20.8 for no 'apparent' reason.

Pressure test intake?
Pressure test cooling system?
Check Compression?
Check/replace O2 sensor?
Check injectors for sticking/leaking?
Check timing?

Why does it pull less vacuum up to a certain point/ECT? Why/how would ECT affect vacuum?
But if it is pulling more vacuum, and an injector (brand new nismo 740s) was leaking/stuck, it might draw in more fuel, possibly not atomized, pulling raw fuel into the engine and causing it to miss fire.. ? IDK..
I did have a problem with a new RC injector on my RX7 that had something in it, causing it to dump fuel, it was bad though. But when I checked the fuel pressure, it didn't leak down really quick or anything.
 
What kind of plugs are you running? Heat Range, Gap etc etc.

Also have you tried doing a leak test on the motor cold and hot? You might be surprised to find a slightly warped valve or cracked seat that seals it's self when it gets warms.

Also double check that your wideband is reading properly. If possible free air calibrate it.

A cold motor wont pull as much vacuum as a hot motor.

Too lean a AFR will create less vacuum than a good AFR will. But 14-15 is hardly lean. You usually won't run into low vacuum caused by AFR until the very high 15 low 16 depending on the motor. Some can even idle on 17 but that's usually a high comp n/a motor.

If you want faster reply's you can hit me up on IG or FB MSNGR. DM if you want.
 
Discussion starter · #118 · (Edited)
Been frustrated with it and haven't even checked it out yet. I went camping for a few weekends. Fucked up and got drunk and fell in some poison oak. Here is a link to an image of my leg, but click at your own risk. https://imgur.com/SCS2sMh Horrible shit. Itchy, painful, and now swollen.

Scoot: BKR7EIX iridium plugs. Gapped from factory. No leak down. I hope it isn't something to do with a valve/seat. I am concerned about the WB because again it's in the stock location just after the turbo, but just by the the smell of the exhaust, and under cruise/boost it 'seems' right. So, the thing is, it's not like it's cold and runs crappy and lean, then slowly, as it warms up it goes the other way, it's kind of like a switch. Crappy then at some sort of point/temp it just flips rich and higher vacuum. Fucking Weird. Nismotronic guy, John, said he didn't see anything in the tune that would cause it. Almost like there's a leak, causing low vac, then it clears up at a certain temp.

Anyway, I thought I'd give an update and I'll start diggin into it in the next few days/weeks and hopefully I can figure it out.

6/10 Edit:

I took the shitbox up to get some eye ointment for my dog that has pink eye and I noticed that when my fans kick on the voltage drops to about 13.4 volts and the AFR's go up to 14-14.3, idling fine, the AAC goes up to about 48% Vac down to 19.3. Once the fans kicked off volts go up to about 13.6, AFRs to 12.9 and Vac up to 20.3 and the AAC drops to 43%. I will update with a few screen shots showing this. I have no idea, but it seems the voltage may be affecting something or a couple things, maybe poor grounding or something?

Edit2: I do have a disconnect switch for the negative side of the battery at the rear of the car with a ground cable from switch to chassis. I might try to take that out of the loop and see if I notice any change in voltage. Doesn't work as a kill switch anyway.

Edit3:
 
Discussion starter · #119 · (Edited)
I'm just throwing parts at it at this point. New alternator, seems to have made it worse, tried adjusting a few things on the ECU, nothing. Just ordered a new fuel pump. Going to add another ground to the battery. Every time I try to find or fix the issue with it, I just get frustrated and it kills my motivation. Drives fine. It's literally just the idle that's pissing me off.

8/3/20 EDIT: Something I changed on the ECU is causing it. Trying to revert some of the idle settings back I've gotten it better, but not good enough for me. Still pissing me off.
 
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