Alright this is kind of a Superchager type question but also an EU type question at the same time. Im running DW 555's with Emanage Ultimate on a DEK swap in my 96.
I have my setup all back together, 00VI, Pathfinder TB, IACV Block all sealed up perfectly without any type of vac leaks and I have a perfect A/F while cruizing and at idle....

My start up have been....crank it up.... starts fine and then completly dies. I have to assist with my foot to keep it running and get it to stable out. Once its running, I start driving and any traffic light or stop sign the engine completly stalls out. It will suffer down around 400 and either stall out or just recover. Once the car is warmed up, the problem doesnt occur any more. It does suffer but doesnt really stall out completly.

My question is, do you guys think its a riching out problem or some type of vaccum leak?? I have up an i/j adj map pulling fuel and a temp map for that I dont really have all that adjusted yet perfectly. The more and more I mess with it, the closer I get it then another day itll just be really bad.

Any help is appreciated with guys running 555's. Maybe this is a TPS problem but its perfectly adjusted.

Im really besides myself right now...Im about to give up on this car !!!!

-matt

 

something similar happened to me and it turned out to be my maf was dirty.. cleaned it out and it worked better.. hope this helps some..or maybe emanage is sdjusted off? my dw555cc/2.62 pulley/z32 maf setup works almost perfectly without any emanage tuning yet and idle fuel pressure is set to 34psi.. maybe a bad connection to the sensors or emanage?

 

just give up

 

Nah I can definetly fix the problem...I just need to find the source...who knows how.

-matt

 

Have you checked the iacv set screw/base idle setting?

 

I used to have the same issue with my DEK swap but not to your extent where it would stall out at a stop light when its cold. When I first did my swap, I had cold start issues where it would stall if I don't tap the gas for a second or two. One day I was messing around with the screw on the TB where it pushes out the TB plate. It took some adjusting but ever since then it never had an issue starting . Whether cold or hot. I never touch the TPS like many had suggested for the surging problem. IACV screw didn't do crap for me either but try everything out. Good luck!

 

I thought your not suppose to mess with the idle set screw on the TB ?? My iacv screw does nothing and I took off my TB to adjust the TPS and its still perfectly in spec with an OHM meter....should I crack the TB open a bit and re-adjust the TPS or what ??

 

first thing I did was set the TB screw, and let the car idle.. never shut off cuz it cant(pedal is in slightly) and then I set the TPS according to the new TB closed position. We've done it for all the cars with the VI swap(6) and only one has a problem and I believe it has something to do with him not settings his TPS correctly.

 

Three questions
1) Do you have your TPS plugged in when you set your idle with the TB set screw ??
2) When you reset your TPS are you using the Hayes manual directions (with feeler gauge's and ohm meter) or are you using the internet directions http://putfile.com/pic.php?pic=main/...4699.jpg&s=f10
3) Any of these with Pathfinder TB ?

 

1) I have set the idle with the TPS plugged in
2) I used the internet directions, 0.5k ohms closed, 4.0K WOT
3) All were with DEK TB.

 

OK I took the TB out today when the motor was cold and checked what I had set at. With it set the way Haynes tell you to set it, feeler gauge and very presice setting, it wound up being 700 at idle and 4200 at WOT. Not to sure how much of a difference it makes with the TB completly warm so I changed it to 600ohms and 4100ohms and WOT and it seems to be better.
I might try and pull it off tomorrow with the motor warm, and reset the TPS to 500 and 4000ohms.

What does it mean when you start the car and it idles low, then surges back and forth for a few seconds then settles out? Very weird.

-matt

 

mine still has that issue only when the a/c is on, i have a feeling it has something to do with the IACV distance from the manifold but im not 100% sure. My VAFC shows it drop to around 510rpm and then come back up to around 650-700range. a/c off, stays around 750 doesnt drop any.

 

I had a real problem with my IACV mounted soo far away then I changed it.
I now have it mounted right near my TB with a IACV/TB Block I had made. I think if I get my motor warm and take off the TB rear quick and get the TPS adjusted, it will be perfect.

 

I have these issues with my 3.5 swap now so I don't think it is EU related. Additionally, my mechanic messed with the TPS. I am thinking he shouldn't have done that but oh well. I think you guys should look more into the Pathfinder IACV for those running the PF TB. I have it wired up and when I first got my car back after the swap...I had no issues. I wish I knew what happened. I have to replace as I think it went bad. Oh well.

 

The Pathfinder TPS and the Maxima TPS, I beleive are the same part number.

Both can reach the 500ohm/4000ohm setting as per Stephan Max.

-matt

 

No....not TPS...IACV. I have a Pathfinder IACV wired in with the throttle body which eliminates the 4th gen IACV. All you have to do is splice the wires. My mechanic hooked it up on my car. And I know a couple other people that know how to make it work.

 

ohhh...well for me, I have my IACV mounted right near my TB with the custom block which definetly isnt the cheapest solution. I have all the passages on my TB blocked off with epoxy anyway.

I think the externally mounted 4th gen IACV is the worst setup. Going from the large ID hose off the intake, through the IACV, down to a 3/8" line, traveling 12 or so inches, then reduced again to 1/4" into the manifold. Just to me, doesnt make sense.

-matt

 

Matt,

I've seen so many of your threads battling all sorts of idling and stalling problems for the past year or so. I would recommend you to go back to more stock-like setup for a little while to track the problems, ie. replace the 00VI with usim or mevi. I know this is a degrading suggestion, but I seriously think that the further "we" stroll away from stock setup, the more shady we are in the woods. There's too many variables now to locate the cause of this problem.

I have had no 00VI cold idle or stalling problems on the 3.5 hybrid install, only reving to redline killed my motor afterwards; but I noticed installing the 00VI onto the 3.0 setup gave me a lot of idling and stalling problems. I decided to replace it with the mevi, and every thing goes away. Sorry to bust your chops on your 00VI there, but I'm just trying to locate a possibility, even though you've made sure of no vacuum leaks or such probable causes from the dek-VI itself, I'd just think it would be re-affriming to give this a try and see.

Aside from probable causes from your various mods and FI, would you consider taking a look at the coolant temp sensors and the knock sensors together in combination? I've one 95 maxima that's been having this same symptom like yours, but it is stock, though. It was hard to keep it running at cold start, but once it idles warmly, it was fine. but then at stops and intersections, it would often stall quietly on me. I noticed it often idles down to 500 rpms at the intersections and dies out shortly. Then I always try to adjust the IACV higher to keep it from doing it, but none of the adjustments would help fixing the problem. I didn't know the real cause until "7-months later" that CEL's came up for the coolant temp sensors and the knock sensor together. I later found the knock sensor to have a small crack and replaced both sensors on the coolant's main duct. The problem got fixed afterwards. Drives fine, and idles fine in all rpms and intersections. I was suspecting that the coolant temps went bad for the whole time till the knock sensor finally gave up, then the ecu threw the CEL for the both of them.

Just trying to help...

-Peter-

 

I totally hear ya but ALOT of the parts that I have on my motor, including the knock sensor and the ECTS, are NEW. Not ebay new, but Nissan NEW. Also the IACV, many of the sensors, Injectors, are all new.
This is definetly a setting problem on either the TPS or the Emanage that is throwing everything off. Now that I have that huge vac leak fixed that I had for months, I can finally begin to fine tune everything to perfect. I had the car out today with the new TPS setting, and its a hel* of alot different. Doesnt stall at all any longer and is holding a perfect idle. The TB/IACV Block really makes a diference with the 00VI swap on the 3.0. Thats why your mevi was working better. The IACV needs to be close.

Thanks for all your help.

-matt

 

Im having similar problems with my car on the cold morning starts. So I guess I should get the TB/IACV block and see if that helps.

 

If you look at the stock IACV location. Right on the Manifold.

Then look at the 00VI location alot of guys are using ==> Large ID hose off the intake=====>Through the IACV ====> 3/8" line ====>Travel 12"====>then reduced again to 1/4" into the manifold. Motor isnt getting enough air for start up.

 

Glad it's getting better for you Matty.. TPS huh.. I'll be redoing mine soon.

The other possible way without changing the IACV might be to permanently crack the TB plate open a bit with the set screw

 

My one question about that is, whould that effect Idle speed when warmed up ??

I was thinking of doing that to help with cold start a bit, and then just adjust the TPS once I have it cracked.

-matt

 

I honestly dont see why you guys are having problems with the 00VI swap, since the day I installed this manifold cold-start, warm start, doesnt matter as soon as the starter kicks hard enough to get the motor running the rpm launch to around 1200 RPM and then come back to 750(my IACV isnt working probably, obviously). There is no irregular stalling what-so-ever, although the RPM's do ride low when the a/c is on(again IACV problem).

Some instances when it had been raining during the night that the car will start up and then flutter around 450-500 and shut off. It has only happened a hand full of times and it might have something to do with my filter being so close to the outside elements(2-3" behind the fog light). Start it up again, and it will choke(injectors blah blah, and then tap the gas for a second and its all gravy again).

I dont recall any of the local guys who myself or others have done the 00VI swap, 3.5 swap, etc for that have a extreme cold start issue like you are having. The only one I can think of is streetzlegend which I wouldnt touch that with a ten-foot pole. If you guys look too hard to find the problem you may never find it take a breather and you might just find it right under your nose.

 

That has worked time and time again, but I dont see why people are so against it. Before I took that route I did try and adjust the IACV but the before swap IACV just wasnt cooperating no matter how I twisted that lousy screw.

 

The funny thing Luke is when I first swapped the VI I had no issues either. Cold and warm start up, no problem, ran just like stock for a long time. The sputter on initial cold start only started last fall, but I've never had a stalling problem other than that. I was too busy to address it then and to me it was only a minor inconvenience, but this year once I get the car up and running again I will probably spend a bit more time hunting it down.

The IACV setting procedure as per the FSM doesn't always seem to work properly I think....

 

Exactly what I was suggesting. It has worked for me and I don't see any reason why it would be any different for anyone else. It wouldn't hurt to try it and can be set back if it didn't work...