Cold Starts.

[KezR33]

My car really struggles in the morning. I'll start her up and head slowly down the street, and at about 3000rpm she starts stuttering. When I got to the highway I couldn't get passed about 90km (in fifth gear) before she starts struggling. It is normal to be this bad? When she's warmed up she runs great, but these cold mornings worry me.

[Bumblebee]

it shouldnt do that.. its EFI hahah a carby would do that coz the chokes still gonna be on, but an EFI system eliminates those problems

[steven22]

Same with mine mate, apparently it might have somethimg to do with the water temperature sensor thats connected to the ecu, or something like that.

[Bumblebee]

i read ur post as well.. urs is different.. u said u gotta keep urs above 3k otherwise its poo.. this ones the other way around.. goes nice till 3k

[R338OY]

Air flow metre or oxygen sensor need cleaning/replacing?

[sh@un]

does your car have an aftermarket ECU?

did the tuner bother to do the cold-start map properly?

[Dicer]

Might sound dumb, but what fuel are you using?

[GTS4WD]

Reset the ECU

See then

[342Four]

or it could be the coolant temp sender

but i reckon reset the ecu, then see how it goes....

[KezR33]

I don't know if my ECU is stock or not. It seems there is another problem involved, it is only enhanced when the car is cold. I had the same problem a few weeks back where my muffler had imploded and we thought all the shit jammed in the muffler was restricting the airflow. Had the muffler replaced, car was running great, but now it's starting again. When totally warmed up (I took her for a long drive tonight) she starts choking at around 5-6 thousand rpm.

Before I had the muffler replaced I had my mechanic look it over, I don't think he did any serious inspection, but he definitely ran tests on all the electronics and said everything was fine. I guess I'll give him a call again tomorrow. Could it be that it was my front (is that what they're called) muffler is f**ked too, and that the shit we pulled out of the rear (steel mesh) was originally from the front, and now it's just building up again?

Thanks.

[GTS4WD]

When totally warmed up (I took her for a long drive tonight) she starts choking at around 5-6 thousand rpm.

lol.. Yeah.. Its a stock NA 6cyl. Its going to do that while your rev the chops off it.

Id say Reset the ECU first..

Then go see..

I have a rattle in my resonator box on my NISMO cat back.. does go away once the engine is warm (similar to what your experiencing) but it doesn't and shouldn't hinder performance..

P.S its not good to be driving your car hard when cold either..

[dori34]

mine has a similar issue as well..

when i start it up after leaving it overnight or after more then 30minutes, its struggles to start unless i step on the accelerator to give it some help..

if i dont step on the accelerator, it just cracks, starts up for a split second and turns off

but if i just stopped driving, turn it off and start it again 5-10mins later it starts up fine, what could my issue be??

[R338OY]

mine has a similar issue as well..

when i start it up after leaving it overnight or after more then 30minutes, its struggles to start unless i step on the accelerator to give it some help..

if i dont step on the accelerator, it just cracks, starts up for a split second and turns off

but if i just stopped driving, turn it off and start it again 5-10mins later it starts up fine, what could my issue be??

I have the same issue. Advice would be good!

[GTS4WD]

I had a similar Issue after I did my RB20 to RB25 conversion..

This may not work on 33's and may not work on Stock NA's.. but I had something called a FPCM - fuel pump control modeul. I re-wired the circuit around ti so that it wasn't in use. I did it because I Had a look at the R32 Rb25DE fuel pump wiring diagram and then compaired this to the R32 Rb20DET and it was not present in the DE diagram.

Alturnatively.. Cheak AFM/reset ECU/TPS/Injectors.. theres a world of causes to "hard starts".. If you can get your hands ahold of a Nissan workshop manual it can help diagnose the problem

Edited March 28, 2008 by GTS4WD

[KezR33]

lol.. Yeah.. Its a stock NA 6cyl. Its going to do that while your rev the chops off it.

Id say Reset the ECU first..

Then go see..

I have a rattle in my resonator box on my NISMO cat back.. does go away once the engine is warm (similar to what your experiencing) but it doesn't and shouldn't hinder performance..

P.S its not good to be driving your car hard when cold either..

My rev limiter is at 7000rpm, I've gone beyond 6000rpm in the past with no trouble.

I don't drive hard when she's cold either, like I said the car struggles at only 3000rpm, that's about the point I normally change gears.

How do you reset the ECU anyway?

[dori34]

^ disconnect the battery, let all the power drain by pressing the brakes till the light slowly dims away, give it 5mins, connect battery back up and thats it.

or i duno if theres a reset button on the ecu?? lol

[342Four]

no reset button

the above way is the way to reset the ecu - pressing the brakes drains any capacitors that may contain charge still