Silkk

iTrader: (11)

Okay, so here is a little historical information: My Z has never had an issue starting and staying started/idling prior. The car has always idled a little low in the 500-600 RPM range, but this was never an issue. In any case, Friday I spent a few hours at Altered Atmosphere and had some test pipes installed, as well as the AAM Reflash/Tuning performed. After the TPs it was onthe dyno. Over my last dyno from about 9 months ago and 40k miles ago I picked up about 5hp after the test pipe install. Then it was on the dyno for about an hour and half getting flashed about 3 times and tuned. I came up with ~10hp/~15tq gain at peak (and a 14hp/15tq gain throughout the entire RPM range) over the first run of the day with the TPs (total gain of 19hp/15tq or so).

Anyway, the one detrimental effect this seems to have had on the car is the initial ignition of the vehicle. When warm the car will start just fine (RPM's rise to about 1200 or so), but it seems the RPM's fall pretty quickly toward the 500RPM idle and the car will just stall out. It will not remain started unless you blip the throttle once or twice or feather it a bit to keep it at 750+ RPM for a second or two. If you take this latter action the car will settle to the normal 500RPM idle and remain started. The car runs perfect and much stronger once it is running. When coming to a halt the car settles to the 500RPM idle just fine and does not stall out. I should also note that when the car is cold it idles around 1000RPM. The car will start just fine, with no additional throttle feathering/blipping, when cold and remain started due to this higher idle.

What could be the cause of this? Is it the testpipes (AAM 2.5") or something with the flash? AAM didn't seem to know and has never seen this before apparently. Is there any resolution? Is there anyway to adjust the idle up 200RPM? Would I do this via the ECU or is there some sort of throttle bump/stop bolt on the throttle body that I could adjust so that the TB remained open about 3% or so at idle?

Thoughts? Questions? Concerns? I'd really like to get this resolved even though it is not a huge issue at this point. I drove the car all weekend with no problems other than forgetting once or twice to give it the throttle at startup and stalling it out, but as long as I remember the car starts and runs fine.

Thanks for any input.

blasian

iTrader: (29)

Try reseting the ECU using the pedal method. When I installed my Pop Charger and disconnected the ECU for a night to reset it, my car wouldn't idle when warm. It wasn't until I reset it with the accelerator pedal that it idled properly.

Hope this helps.

Silkk

iTrader: (11)

Got a link to the reset using this "pedal method".

Will this reset the ECU reflash/tune I paid $900 for?!

blasian

iTrader: (29)

I doubt it'll reset the tune but you may want to call and check with them first to make sure.

http://www.technosquareinc.com/350reset.htm

Also, the car should eventually relearn on how to idle. Mine did but it took about a week lol.

Mike Wazowski

iTrader: (113)

reset will not do anything to your reflash.

Silkk

iTrader: (11)

Awesome. Thanks guys.

I'll give it about a week to figure it out (hopefully) before trying the ECU reset. I'm a little concerned it may never learn to idle correctly as it idles correctly at all other times other than a warm startup. Warm running temp idle at redlights, etc. is perfectly fine?

Ah well. We shall see! If the reset doesn't work or it doesn't learn, I'll post back.

I did a search on "stall" and found someone else who had a similar problem and someone suggested performed a throttle position relearn procedure. Is this the same as the reset or something different?

blasian

iTrader: (29)

If you do an ECU reset, it will take care of the throttle position relearn procedure if I'm not mistaken. Like I said, I did the ECU reset after the second time I had this problem and it fixed it

Silkk

iTrader: (11)

Will attempt this asap once I confirm with AAM that it will not alter the reflash I just paid an arm and half my left leg for.

KPierson

iTrader: (1)

You can raise the idle by using a consult tool or a Cypher.

Silkk

iTrader: (11)

Mike at Altered confirmed that ECU Reset does not reset the ECU Memory (Flash Coding), so I am going to attempt that. If that does not work, I will get the dealer or someone to bump idle 200RPM for me.

JonsilvZ

Your the one with 90k miles right? How does it run? Did it loose power? I only have 34500 on my 03 Z

Silkk

iTrader: (11)

Car is running great (knock on wood) for having 90k miles. It may have lost a few hp from wear and tear, but I cannot be sure. I dyno'd around 50k and I dyno'd after the test pipe install and I picked up 3hp. Seems a little weak for TPs, so that's why I *may* have lost 3-4-5 hp from wear and tear of 40k miles (i.e. AAM test pipes claim 8hp gain or so and I only saw 3hp from my prior dyno). The only way to know for sure would have been to dyno at 90k before the TP install...

Either way, I think the car is still running strong for having 90k. I have the bolt-ons in my sig and it makes ~255hp/237tq. Not bad considering I'm missing headers and my exhaust is not a true-dual design. I do not have lightened flywheel or anything either. I know Zs with normal boltons and tune/flash normally are in the 260-265-270whp range, but I would be right there after headers, so I think its still running pretty darn good. Most people don't break 265-270 without flywheel, cams, etc.

I also haven't had a true "tune-up" done yet to 90k. I replaced tranny fluids around 35k, but not since. I flushed coolant around 35k, but not since. I've never changed spark plugs, etc. So, might even pick up some power just by doing some routine maintenance, but who knows? If it's not broke don't fix it?

JonsilvZ

You definitely need some new plugs and fluid changes. My 95 Benz C36 AMG with 90k miles runs high 13s in the 1/4. It runs better then new! I guess because its handcrafted and has forged pistons and stuff.

Silkk

iTrader: (11)

Yeah I guess I should get a "tune-up" at some point. May be a early May project...

live2themaxuk

iTrader: (2)

has this fixed ure problems? Im having the same thing after i recently disconnected my battery, not it wont bloody start up properly when warm. Done all the technosquare tutorials, still crap.. . . .

Jay'Z

iTrader: (118)

Silkk.. I know you may not know this but there are plenty of people on here with that same problem. I found the problem to be the idle set. The only reason I found that to be the problem is by Mark@SGP recommending I get a reflash and set the idle to 900-950 which I did and problem solved. I have never had a stall since!


Note: Uprev did my reflash..

FALLEN1z

i had the exact same issue and the solution was the #2 cylinder fuel injector was bad, so they replaced that, cleaned the rest of the injectors, and the throttle body. and also the MAF needed to be replaced. that seemed to have fixed it

live2themaxuk

iTrader: (2)

Oh dear oh dear this doesnt sound good. Its just odd that it has co-incided with my recent disconnecting of the battery. I never had this problem before the disconnection, i have NEVER had it not start up correctly when warm, its doing it everytime without fail and hasnt 'come on' gradually. . . . . its definetly something related to the recent disconnection.


Jamie

Silkk

iTrader: (11)

I haven't yet reset my ECU; still living with just a throttle blip to keep it started. Once its started it idles and runs fine...

I may get Nissan to raise my idle if need be... Or AAM might do it for free since they did the flash that caused this?

For now, I'm dealing with it though. I would say the person above who said "#2 injector, clean the rest, buy new MAF" probably got taken across though. I can't think of a reason the injectors would be causing this and I just recently (10-15k) replaced all my injectors so they should be fine. MAF could be the cause, but I'd lean more towards it just being an idle/ecu problem as I never had the problem before, it idles fine at 500RPM once it stays started, etc.

I'll do the reset soon and see if there is any dice...

live2themaxuk

iTrader: (2)

Well ive done the pedal reset and so far, no joy.

There are 3 other things, Accelerator Pedal Release Position Learning,Throttle Valve Closed Position Learning, and Idle Air Volume Learning (Throttle Position Learning) which i have all followed, but they are all really 'vaugue'.

With the ECU reset at least you know you have done it correctly as the milage resets, but with the others, there is no way to 'confirm' that the WHOLE procedure has taken effect.

1) on the 'Throttle Valve Closed position learning' prodecure it says 'Make sure that the throttle valve moves during above 10 seconds by confirming the operating sound'. What the hell does that mean? What sound is it supposed to make when im not even touching the throttle?

2) In 'Idle Air Volume Learning (Throttle Position Learning)' it says the following

9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.

well, when i 'start the engine' it doesnt bloody idle. . . .thats the problem, so how am i supposed to start it and 'let it idle' . i do, but it takes 3-4 turns of the key to get it into a state of idle without cutting out. . .

Hard to know if i am doing the procedures listed on here correctly

http://www.technosquareinc.com/350reset.htm


Maybe someone could clarify

Jamie