Car Wont Start When Warm.

[Jap_star]

Bit of an interesting one here.

Car starts up first time every time on a freezing cold morning. But if you drive the car and turn the car off for a short period of time it just wont start again. this isnt really an issue most of the time but if you duck into the shops for a minute, you have to wait about 10-15 mins before the car will start up again. Car has only started doing this since all the parts were put on and tuned. plugs have been gapped down to .8 from 1.1, brand new battery (550CCA) .

It cranks and cranks but just doesnt fire. any one have any ideas?

car always started fine with nistune and usual bolt ons. now has Z32, bigger injectors, pump. All of which were brough brand new

anyone care to hazard a guess at what it might be

thanks

[DVS JEZ]

Could need a new fuel pressure reg, might be boiling the fuel in the rail.

Possibly needs more fuel added on hot start

[Jap_star]

same thing my tuner said, might put one in and go from there.

[blind_elk]

Was the ECU ever tuned for warm / hot starts?

And why are the spark gaps at 0.8? Are you making serious power out of this engine?

[Jap_star]

was advised to gap down to 1.1. this didnt make a difference at all.

Im unsure if the ecu was tuned for hot/warm starts. It does it that randomly thats its hard to say/

car only makes 270rwkw. so its not that.

Hasnt done it since i popped this thread up. even with a few short trips to the shops today. which was nice

[dorifticon]

Hasnt done it since i popped this thread up. even with a few short trips to the shops today. which was nice

Intermittent problem starting when car is warm - exact same problem happened to me in my 300zx (z32 TT).

Does yours stink like fuel when it's trying to start and occasionally run like s--t? Mine did.

Problem turned out to be the coolant temp sensor - actually, the sensor itself was fine, the wiring just near the sensor had corroded.

The coolant temp sensor was intermittently failing.

When the car was cold it was fine, because the ecu thought it was cold. WHen the car was actually warm, it would basicaly attempt cold start up and dump heaps of fuel in.

Because the sensor would work intermittently, sometimes it was fine and sometimes not. At first, it would struggle to start, but then be ok. It deteriorated until it became a problem when running.

Cut out the corroded wire, reattached to the sensor, and it was all fine.