Motor Dies after cold start (unlessed rev'd)
 

Resolved on page 2

Hey guys this issue just started showing it's face about a month ago and has progressively gotten to the point now where it'll turn the car off.


Symptoms:

Cold starts after cranking idle drops extremely low and car dies...when i first noticed the problem it would idle low then pick back up as usual but now turns the motor off everytime

Can give the car gas to keep the idles up in the mornings or after extended period of non use and that obviously will keep the idle up and the engine will stay on.

Car drives fine and cranks flawlessly throughout the day, no issues at all.


Troubleshooting i've done:

I've only tried the fuel antifreeze/injector cleaner stuff since I initially thought this was related to the cold weather but now that it's warmed up I see that has no bearing.

Cleaned MAF, no engine codes.

Fresh spark plugs

Additional info:

04, AT, 160k, non garage parked.


Thanks in advance for any assistance

That's so weird....cause My engine is doing the same...it will sputter and seem like it is getting choked or something.....then if I keep the throttle open a bit it will rev up and sound normal....but if I let off it will eventually die !

I'm gonna have to take my car back to Steve kan and se if he can figure it out.

I've had this problem come and go for a while now over a few years....but it has never been this bad before.....I have a video of it and will post it up soon.

lol hilarious, it's a PITA

JaE35z....here is my vid....

Yup that's it..yours is a little more aggressive than mine but I'm sure it'll get there soon. I'm gonna try and record it in the morning.

Sounds like an old carburetor car struggling. I might be way off base, but my guess is there is something wrong in the computer that controls the idle based on temperature. That's not specific I know, but a starting point. :dunno:

Chris, does your SES light always stay on that long?

had the exact same problem when i had BC stage 2 cams installed. Took them off and now i'm ok with the oem cams.

I agrre with the post about your prob being temperature related.Old carb
cars had a choke system.First manual them went to a auto choke.Early
fuel injection systems had a similar device that provided "heat" and a richer
mix until the car was near normal operating temp.It could be the problem
is related to a sensor.I'd check my cam sensors for one.They do crazy things
before going completely out.With 160k on your car,if you have not replaced
one or two of the cam sensors by now,that would be rare.

I've replaced one of the can sensors within 40k miles ago

I had this issue for a bit, not as severe, but the car would bog down and almost die. I did the seafoam thru brake booster/tank and only fill up at gas stations with techron (supposedly it has injector cleaner in it.) Since then I have not had the issue. Maybe give it a shot?

I did seafoam on my 02 altima with 120k, apparently it released s much gunk it damamged 1 of the piston's rings. Maybe the car was on its way out but......

I agree, check the crank/ cam sensors if they are bad. I was going to say fuel filter may be dirty, but I dont know if the Z has one. Good luck man.

The Video I posted was when the car was warm....it pretty much does it all the time, whether cold or after I have been driving for a while....I had the Throttle body replaced a couple years ago from Dealership while it was under warranty....but it came back after a good while later.

I have an UpRev Tune and the tuner can by-pass a lot of stuff, and last time he said my AFR was really lean....also there was a difference between the left Bank A and the Right Bank B for some reason. He leveled them out and it ran great.

Also, my car does this whether or not the CEL is on or off. I have HFC's and i periodically throw a CEL and it is always the 02 sensors. I have an OBD II so I can erase any codes.

I think I am going to change out my fuel filter this coming week and see if that helps.

I don't believe it's the cam/crank sensors..that would throw a code and be more consistent. I'm going to change my coolant temp sensor and pull off the racing thermostat and see if that helps.

Are there any pending codes? Sometimes codes could be stored in the ecu but not actually be triggered. But generally that's for evap codes like p0446 or something.

Nah if there were codes that would be great as far as diagnosing this, i keep a scanner handy. I do know i have a little air in my system however...i'm on the fence on whether this is fuel related or coolant temp

I am leaning more towards the MAF sensor confusing the AFR to lean out the fuel to the point where the car will start to sputter and die.

I'm going to to try and change the Fuel Filter, change my plugs, maybe look into either cleaning or replacing my injectors. Maybe look at the 02 sensors from my HFC's.:dunno:

I'd start by checking your Idle Air Control (IAC) Valve. Consult the FSM for troubleshooting and at least give it a good clean-out. Check your IAC it with an Ohm meter. If you're reading zero, then the solenoid is bad.

Hmm, i thought our fuel filters weren't serviceable? I'll definitely look into the IAC valve, thanks zakmartin

have you tried the relearn procedures yet?
http://www.technosquareinc.com/350reset.htm
OR
https://my350z.com/forum/maintenance...procedure.html

generally if you perform these procedures, and the symptom goes away temporarily, then come back its a throttle body.
otherwise if it actually sounds like the video, the timing may be off, either due to a sensor, timing chain, or actuator issue

a video of your problem would be helpful

vid will be up soon, i just hate letting it die..it hurts to see my baby struggle, i'll try the relearn and report back as well