Mystery Fuel Issue....

[slydnn]

Was out driving my r33 S1 today when i noticed alittle miss under load every now and then. Thinking it was a typical coil pack issue i just took it easy.

It started to get worse and is clearly not a igntion issue, it apears to be fuel. Everytime i try to give it gas it hesitates but it will still idle?

End result was a tow truck ride home, and just to add insult to injury when i got it home it still runs and drives fine?!

This is a heavily modified rb25det but this has got me beat. Its never let me down before but reminds me of trying to drive it with a intercooler pipe blown off. (if that makes any sence)

Pump is still working, ecu tells me that the duty cycle on the injectors is normal. I did fuel up 30 minutes before i left but does not have the characteristics of dirty fuel...Somthing is failing when it gets hot, but what?!

Good brain teaser for the crew..

On a foot note, the only person that stoped to help me push the car off the road was a fellow skyline driver! Full respect mate.

[blind_elk]

The ignitor module is prone to problems associated with heat.

Try also replacing the fuel filter.

[slydnn]

i was thinking the fuel filter and regulator to start with.

Not sure it is a ignition problem as it doesnt drop cylinders it just dies all together..

[Carbon 34]

Was out driving my r33 S1 today when i noticed alittle miss under load every now and then. Thinking it was a typical coil pack issue i just took it easy.

It started to get worse and is clearly not a igntion issue, it apears to be fuel. Everytime i try to give it gas it hesitates but it will still idle?

End result was a tow truck ride home, and just to add insult to injury when i got it home it still runs and drives fine?!

This is a heavily modified rb25det but this has got me beat. Its never let me down before but reminds me of trying to drive it with a intercooler pipe blown off. (if that makes any sence)

Pump is still working, ecu tells me that the duty cycle on the injectors is normal. I did fuel up 30 minutes before i left but does not have the characteristics of dirty fuel...Somthing is failing when it gets hot, but what?!

Good brain teaser for the crew..

On a foot note, the only person that stoped to help me push the car off the road was a fellow skyline driver! Full respect mate.

My money is vapour lock

All symptoms sound like it

Depending in mods

Fuel boils in the lines or filter and the engine dies and wont restart for a while on hot days or lots or stop start driving

Next time it happens remove fuel cap and see if it starts that drops off over pressure in the tank

any leaks or water in the fuel does it

So does e85 fuel , ethanol and super hot days don't go together

[blind_elk]

Highly doubtful its vapour lock. Not with 40+psi behind it. Increasing the pressure raises the boiling point of liquids. And the pressure would push any vapourised fuel through the system quick smart.

[slydnn]

narrowed it down this arvo, definatly fuel pump! Its got a bosch 040 in tank in it and over the past few days i had been thinking to myself that it seemed to be louder than normal??...took it for a drive today until it started playing up and i can hear the pump reving up and down all unstable.

So out it comes tomorrow!

Case closed,, thanks for the input guys