Starting Problems, Mostly Hot Start

[inissane]

Hey guys,

k over the last few months i have a worsening starting problem in the RB20DET. Battery is cranking it fine and starter too but it just doesnt want to turn it into an idle

Im also experiencing clutch in/braking stalls at lights which is particularly fun when it takes 10 cranks to get it going have to heel toe gas to keep alive mostly

cold start - about 1 in 3 cranks it will start

hot start - about 1 in 10 cranks to start the bugger, and both scenarios require throttle to gain a stable idle

I also had a miss a while back but replaced a faulty coil and renewed spark plugs and its now running very strongly and quite smooth.....when it finally gets going that is

other info:

battery new and charged

afm recently cleaned

aac valve cleaned

pretty sure no vaccum leaks

040 fuel pump earthed to chassis (not ecu) as per thread on here

Ive done a bit of research and from what i can gather possible causes of this could be:

leaking injector/s or fuel pressure reg??

faulty coolant temp sensor

ignitor faulty/ overheating

coils again, but there is no miss really and power is good??

Thx for reading would really apprec some input/help/ideas as to why it doesnt want to start properly and stalls now and again!!!!

car has:

rb25 turbo, fmic, pod filter, stock bov, 10psi, remap ecu, exhaust

ps- could start maps be crud on the remap?? just an afterthought but problem has been worsening so maybe not

[R33S2]

How hot is hot, does the coolant look dark or need refilling?

[inissane]

yep thats also happening coolant is rusty dark and have probably needed to refill more than normal.....engine head has been reconditioned a little while back tho......

i think ur onto my prob Terry....tells me

[R33S2]

I hope this is not your problem but I had a car that did this same thing, turned out to be a hairline crack in a inlet valve housing to water jacket, it only did it when the motor was working, ie if I stopped for awhile it would be ok untill engine reached a certain level (temp didnt move much) it eventually opened enough to fill a cylinder, that shot into the air when I cranked it over lol (no plug motor wouldnt turn over).

Its strange but I just posted that the other day on a topic about non reving motor (cue in twilight zone music)

[inissane]

nooooooooooo............say its not so.....how do i get this tested for??

about a year back the timing belt/water pump was being replaced in a certain Syd imports/skylines workshop and they farked the head by turning it over with no timing belt or something totalling a valve - causing no comp in that cyl

they then sent off the head to be fixed and put her back together, duno if that means anything here but yeh

thnx for ur input Terry

[R33S2]

Bubbles in the radiator are a bad sign.

[No Crust Racing]

Just one to add to the mix, I had a hot start issue and random stalling with my RB25, it was a comob of dead o2 sensor and stuffed Cam Angle Sensor earth. Just some other ideas.

Good luck

[KamikazeR33]

i was gonna say perhaps 02 sensor