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for the past few months now, my car is realy hard to start when its hot. cold start is perfect and fires up straight away and idles perfect, but when the car is hot and i turn it off for about 15mins or more it takes along time to get it started, it just keeps cranking, then it goes to start but the revs are very very low and you need to continue cranking until finaly it starts, sometimes have to pump the accelerator to help it fire up !

ive also noticed if you turn it off, then back on after only afew minutes it will start first go, no probs :S so only happens when its sitting for about 15mins or more...

things ive tried/replaced but still no luck:

turn on the ignition and let fuel pump finish priming then start. still no different

new coilpacks/coil pack loom/spark plugs

Sard 280lp/h fuel pump with direct battery power feed

timing belt quadtriple checked and timing is spot on

compression test @ 160-162psi accross each cylinder

r33 gtr air flow meters, cleaned and tested

its realy annoying any help would be great !

tonight i went for coffee with the misses, got back to the car and it wouldnt start for ages, just kept crankiiiiiing seems like it could be getting worse

thanks guys

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tonight after coffee, the car was sitting for 1 hour, it just wouldnt start, the worse its ever been ! kept cranking and cranking then went to fire but the revs were so low it died and continued cranking. :S

ok il give the temp of the car when i go to restart it and it does this

also it was doing this few weeks before i got the nistune, so got nothing to do with ecu

mine did this with a vq motor.. turned out to be plugs where in the wrong temp range so when the engine was hot. they just wouldnt start n felt sluggish for a second or two if it did..

also if o2 sensor is screwed it can screw up fuel mapping on start up.. hope you find the problem mate

Mine also does this but no where near as bad. Starts almost instantly when I turn the key on cold start, but when warm it cranks a little bit then fires and I usually blip the throttle a little to bring the revs up. Has been like that ever since I had my injectors installed, so I believe they are the culprit. Doesn't bug me TOO much so I haven't done anything about it.

yeh forgot to mention, changed from my heat range 6 iridiums (were on the car when i got it) to bcpr7es 0.8mm copper plugs, but these made the car hesitate and jerk when driven while cold until the car warmed up. so i ended up putting fresh iridiums in, heat range 6 @ 1.1mm gap with new coilpacks

car still had the iridiums in that were on the car when i bought it and then out of no where started doing this, the problem didnt start after i changed plugs, which i then changed back to the ones originaly on the car as it was running perfect for 1 year with them

thanks for the input guys !

Edited by SiR_RB

dunno but the car basicaly needs to be bone cold ie. be off for 5hours or more so it can start normal, anything less then that and it has the shits starting lol weird :S

Edited by SiR_RB
  • 2 weeks later...
  • 1 month later...

update:

replaced with genuine nissan coolant temp sensor...still does it !

tomorow i will be changing my fuel reg so fingers crossed this solves my problem

according to consult only one of my o2 sensors is working but i didnt think they have anything to do with starts/idling ? plus we tuned around them and i get excellent fuel economy (easy 430kms per tank, and thats not driving like a nana :)

car idles 100% perfect, no hiccups or anything :)

can you check the load on the starter while cranking? both cold and hot

if there is a huge jump in amperage draw from cold to hot then it "may" be an issue in both injectors and spark while cranking.

anyone with a claw type current multimeter could help you out there

  • 1 month later...

my car got stolen. lol.

but i was told it was leaky injectors. go do a search on the symptoms of leaking injectors and you'll see its pretty similar. fires up nicely in the morning. but after going to the shops, coming back 10-20mins later. car needs to crank a bit to get started.

  • 7 years later...
On 3/25/2019 at 5:50 AM, SeanR32GtSt said:

Did this ever get sorted? I’m having similar issues with my r32 gtst

Cranking compensation table wasn't dialed in properly. Was too lean to start.

  • Like 1

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