well the car dies during idle. The problem happens only with UTEC, while using the stock ECU there is no such problem. My mods are below.
What can be the possible reason? I'm suspecting on the injector dead time setting (mine is 1.2 right now). Also the response time of the injectors seem terrible (maybe it's just me, i dont know).

what do you suggest me to do for troubleshooting my problem? There is no CEL and my afr @ idle pegs between 14.1 to 15.5 so it's not solid but the idle is as solid as a stock car except in time periods of 5-10 seconds the car feels like misfiring (the power is gone for 1/4 of a second or so). Checked the plugs and all are fine. While driving the car there is no problem, the afr is solid but when i press the throttle like %2-3 the same hesitation happens but as the car has more power it keeps running.

So what do you think the problem is

 

I'm not sure, but I have a very similar set up as you and I was just on the phone with the shop that's finishing my built Z which was having a similar issue as your car. At first, they thought it was the RC 750cc's sticking open, but it turned out to be a faulty fuel regulator that I got with the AAM fuel return system. New regulator fixed my issue. FYI, I also had Technosquare reflash for a 1000 rpm idle.

 

raising the idle seems to make things a little bit better, i'm keeping the A/C on for that but it only helps a little. Thanks for the advice, I'll try it with a new regulator first thing in the morning, still the fact that problem doesnt happen with the stock ecu makes me think.

 

ok now it is throwing a P0011 code too

 

mistaboosta,

I replied to your request in the other thread already.... it is weird that you will have P0011 code though... that's related to the cam timing... and with the utec, your cam timing controls are left to the stock ecu... I have the cam timing code because my motec takes over the cam control and the vtc operates at the angles that's outside the factory spec due to nismo vtc units that I am using...

But I do have this type of jerking at light throttle at 2100rpm at llight throttle and when my tuner looked at the cam angle gauge when it happens, the cam timing goes from the set value to "0" then back again... it just keeps on doing that until I let go of my throttle or give even more throttle...

It makes me wonder would it be one of the original part (VTC unit) that's faulty to get that code or even a faulty cam sensor?!

cheers,

richie

 

i'm also suspecting on the faulty cam sensor or crank sensor issue. Before utec was installed, i was using the unichip and so i was using unichip's own crank angle sensor. Now i re installed the stock crank sensor back. I'll go to Nissan dealer now and talk to them about this issue. I'll let you know if i can get some results. Have you tried any new sensors yet to solve the issue?

 

mistaboosta,

I have not yet tried any new sensor though... and now I recalled, I never had this problem even after motec was fitted by my 1st tuner... only happened a while after the 2nd tuner re-tune the motec computer... But my curent tuner (2nd tuner) thinks it might not be just as simple as the sensor... I would love to try out with the new sensors, but I just don't have the time to look into that as yet... please keep me posted!

cheers,

richie

 

does the utec still use maf pulldown ref when turbo under 65% throttle like it does NA. the reason i ask is every single time i have a bad idle. it is usually something not REALLY tight from the maf housing to the throttle body. im sure you know what you are doing cause it seems like you have a lot done. but hopefully it is just pulling a tiny bit of air in that the maf is calibrating for.


good luck.

and not sure about the code. this might be another problem that was a coincedence OR the main cause of you current issues.

 

thanks for the input audiblemayhem, i've uninstalled and reinstalled those parts you mention maybe 10 times for the last 2-3 days to check if the injectors,plugs,sensors and some other stuff are working right.

Here is my progress for today,

First I visited the local Nissan dealer. The guy over there told me that it could be something about the installation of the cams, cam sprocets and the timing chain on the cam sprocets/pullyes. He talked about a special method of installing those parts like pumping some pressurized air from a hole on the sprocets or something while moving the cam back and forth until you hear a clicking noise from the sprocets which tells you that, they are correctly seated. He also said that, they wouldn't work if they are not seated correctly. While installing the engine, honestly we didn't do anything like that coz I couldn't find anything like he mentioned on the engine service manual.
Also he checked the car via Consult-II and we saw that, if I'm not mistaken, the intake cam sprocet was not able to give any advance or retard to the timing, I mean there was a graph that showed the amount of activation of some selenoid, which was staying constantly @ 0%. Also the guy told me that he wasn't able to raise my idle via Consult-II.

Later on I went to my buddy's garage where our cars are built. We checked many things from injectors to coils, spark plugs etc. My best guesses for the problem are :

1) Faulty Cam Sensor
2) Cam sprocket error (installation error or something else)
3) Faulty timing chain adjustment (the one on the cam pulleys, tough the mechanic is very sure that they are done correctly)

imho 70% this is an installation error which caused more errors. It can be number 2-3 or something else but that is all I can think of up to now. I'd be glad if other people can read this long post and make their own opinions about the situation. This might help us and some others that are having the same problem.

 

mistaboosta,

I don't think it is the sprocket installation error though... because there are marked points for you to install the timing chains too on the service manual and you cannot go wrong with that... I didn't have that jerking problem right after my engine build, but 6 months later, not too long after a tuning session, it was there (it might be due to the tuning or other things) and still is after my 2nd engine rebuild... and I even have photos taken right before the timing chain cover was put on on the 2nd engine rebuild, I double checked the timing chain marks and it looked perfect! and the easiest way and the cheapest way for you to try it out will be the cam sensors since you don't need to pull the timing chain cover off the car which costs even more...

I was told that if the timing chain or the cam positions were not installed correctly, you immediately have some engine problem, your valves might be knocking the pistons already...

cheers,

richie

 

they might or they might not. my mechanic installed the right timing chain and left timing chain in the same way. The result was, 3 cylinders were running perfect, the other three wasnt firing but we couldn't believe how perfect the car was working, anyway.

Well, if it is not related with installation, then it must be something about the sensors. I hope we can find it out soon.

 

mistaboosta:

Humm i got simmilar problem with my greddy TT setup forged internals and all that Rc650cc injektors,
When my eMangae blue is connected the car get 200-400rpm idle and dies, When i remove the eMange the idle is back but 800-1300 it seems like its not fireing on 3 cylinders.
1400-4000 i cant hear if its any problems , seems fine.

I hope you find whats cousing this!
Might have exactly the same problem.
Im going to try another eManage blue (just in case) but i dont think it will help.
I cant be of much help, first time for me and first TTand first built engine in sweden.

Good luck!

 

i guess the problem is neither e-manage nor utec related, the reason that the cars die when utec or e-manage is connected that they make a significiant lag of communication between the ecu and the sensors which is causing the car to react too late. The ecu is late to make the needed corrections slower than normal and can't hold the engine @ idle.

Z350Philllie,
The reason is somewhere else but can't find it yet. Are u getting a CEL?

BTW, today i disconnected the cam sensor of the left bank and the car was working just the same as before. As my car is 2004.5 i can't find a way to raise the idle so i have to drive around with A/C all the time

anyone else that has more progress on the issue?

 

Also i realized that after going with the build engine my egt numbers has decreased noticably. I'm having 300 C @ idle and around 500 C during cruise. I'm driving the car extremely carefully as the break-in is not over yet, no more throttle than %10-15 and always going off boost, also my max rpm is 3500. What do you guys think of this low EGT numbers? The sensor is just after the turbo @ the left bank of my dual exhaust.

 

I tested the other eMan blue with same results, no difference.
So i agree thats its not piggyback related,

I do not get any cels..
I got a 2004.5 model just like you, mayby its just wrong car to mess with..
Me to have brake in to do, i only have 20km after engine build so id like it to work.

I dont know how much you have played around with your timings yet, thats my next step.

And without the eMan blue the car works better but just a few minutes..

Im keeping my fingers crossed that you find your problem!

Regards
Phill

 

if you have the chance, please watch for the timing values under these conditions during cruise:

%6-8 throttle
(-4) - (-6) psi of vacuum
3000 - 3200 RPM
5th or 6th gear.

Please check how much timing your ecu uses under these conditions and let me know. I think that our cars are using higher than normal timing values!

Also let me know your EGT numbers if you got a gauge for it

 

I got a gauge but not installed yet, waiting for 3" downpipes from aam going to mount sensors then.

Im going to check those values and get back to you.

 

okay nice.

I hope someone that has more experience than us chimes in this topic and offers us some solutions

 

Yes, please help us!

 

any progress?