r34 starting problem

[r34lad]

Hey everyone, I have a r34 GTT s1, im having a problem with my skyline, ive let the car sit in the garage for the last couple of months and havent run it and ive gone to fire her up today and it cranks but doesnt fire, i have been having problems with it previously where it wouldnt start again after driving it around for a bit. It use to start fine on cold start ups but if you drove to the petrol station and fueled it up and went to go start it again, it would just crank and not fire untill you let it rest for a few hours, the car doesn't over heat it sits perfectly in the middle while driving when warmed up. Im thinking this problem has caught up maybe and now it just wont start at all. The car runs on e85, ive checked the e85 seems to be fine. I can hear the fuel priming before you go to start it and checked all my fuses and relays.

List of things I replaced today
- New battery
- New sparkplugs
- New Coolant temp sensor

I was thinking about testing the CAS but from what ive seen online, if the CAS is cooked, the car will actually start up but then die instantly? as mine just doesn't fire at all. Does anyone have any idea or have encountered the same problems? thanks

[r34lad]

Also replace the fuel filter aswell today

[r34lad]

Also to mention, i just tested the CAS, seems to be working fine, can hear the pulses inbetween 0 and 180 degrees, another mention aswell, when i let the car sit for about a hour today, i went to start it and it almost fired on first crank, then just completely struggled. Could it possibly be blocked injectors?, maybe allowing a little bit of fuel to seep past allowing it it almost start first crank?

[dbm7]

Check coolant temp sensor ~ symptoms fit the hard hot start/cold start OK scenario --- if sensor goes open circuit, ECU thinks engine is cold and enriches mixture ....works when engine cold, but floods them with rich mixture when hot (Hyundi MAP engines are a bit infamous for this)...

[r34lad]

I have replaced the larger coolant temp sensor, i do see a smaller one next to it (looks to be just 1 pin) but i assume that is just for the dash? or should i replace that aswell?

[r34lad]

https://www.efisolutions.com.au/coolant-temperature-sensor-bosch-180sx-s14-s15-r33?gad_source=1&gclid=CjwKCAjwzMi_BhACEiwAX4YZUHsCQhbiDT_NC3q5wD9jrzH6Dts9eGSr19NXSDw7x9WVm1sH7G3S4hoCwaUQAvD_BwE

this is the one i replaced today

[soviet_merlin]

46 minutes ago, r34lad said:

it cranks but doesnt fire, i have been having problems with it previously where it wouldnt start again after driving it around for a bit. It use to start fine on cold start ups but if you drove to the petrol station and fueled it up and went to go start it again, it would just crank and not fire untill you let it rest for a few hours

Just a thought, maybe it's obvious: have you tried cranking with the accelerator pressed all the way?

Not being able to start until a few hours later sounds a bit like a flooded engine. Especially if you open the bonnet and it smells like fuel after cranking. Flooring the pedal helps then.

[dbm7]

M'kay....that's the one (single wire unit is just for dash temp gauge as you say) ; auxiliary air regulator is worth checking, and EFI relay of course.

[GTSBoy]

Check for fuel flow out of the outlet end of the rail.

Check for spark.

Try to start with aerostart (or pressure can brake cleaner or similar solvent in a car) prayed in through TB.

If you have fuel and you have spark and it will fire on substitute fuel, then seriously suspect that E85 sitting for ages in your fuel system has destroyed something and put it in your injectors.

[r34lad]

On 4/6/2025 at 6:17 PM, dbm7 said:

M'kay....that's the one (single wire unit is just for dash temp gauge as you say) ; auxiliary air regulator is worth checking, and EFI relay of course.

yeah i have no difference

 

On 4/6/2025 at 6:17 PM, dbm7 said:

M'kay....that's the one (single wire unit is just for dash temp gauge as you say) ; auxiliary air regulator is worth checking, and EFI relay of course.

this has been checked also fine

On 4/6/2025 at 6:28 PM, GTSBoy said:

Check for fuel flow out of the outlet end of the rail.

Check for spark.

Try to start with aerostart (or pressure can brake cleaner or similar solvent in a car) prayed in through TB.

If you have fuel and you have spark and it will fire on substitute fuel, then seriously suspect that E85 sitting for ages in your fuel system has destroyed something and put it in your injectors.

Fuel is coming through fine, have spark on all cylinders, yeah thats what im thinking aswell, maybe its time to replace the injectors