'91Q45 Hard Start

[timatt]

I've owned this car for a month and a half. It has 70k miles and has run perfectly since I purchased it...until this morning. Went to start it this morning (ambient temp 60 degrees; in garage) and it fired off immediately (as it normally does) and then promptly died after running for approximately 1-2 seconds. I tried cranking it using low to moderate throttle position. I was finally barely able to get it started using wide open throttle. After it caught it ran rough for about 15 seconds, then ran perfectly. Before the engine got too warm, I shut it off and tried restarting and it fired off immediately and seems to run fine. I drove 45 miles to work without a hitch.

It almost seems like it initially started on fuel/pressure remaining in the system, then when that was depleted, it shut down. Kind of like what I would expect if the fuel pump was not providing enough pressure.

I've read about fuel pump/controller issues on this forum previously, but I've never really heard anything unusual in that regard with my car.

Any advice, troubleshooting ideas?

Thanks,

Timatt

[skazzi]

Sounds ALOT like the problem I have with my 89 and I also, have no clue.

If anyone has an answer or suggestion, please post. Thanks

edit. Here's a suggestion I found in another thread. It may help.

[quote=""NISTECH""]try holding the throttle to the floor and crank it. if its flooded ,after a bit of cranking it should fire up. your base idle may be to low and its choking on fuel. it needs more air in colder temps to fire since the fuel does not atomize as well.[/quote]http://www.nissaninfiniticlub....80696

[timatt]

The suggestion implies that the car died because it was flooded. I don't think that was the case here. The car initially started immediately, as in less than 1 - 2 seconds of cranking.....then it died immediately, after running for approximately 1 - 2 seconds. It doesn't seem to me that cranking for 1 - 2 seconds would have flooded the enging, particularly since my foot was not on the gas pedal when I started it.

[911/Q45]

If you got it running with WOT and it ran rough for a while, it was flooded. Unlike carburated engines, what you do with the gas pedal doesn't flood an injected engine. If it stalls quickly cold it often floods at restart, I don't think you have a particular problem unless this happens a lot.

[Q451990]

Doesn't sound like flooding to me either. I'd check the MAF and CAS connections at idle. Wiggle them and see if the idle changes. Any idle change indicates a problem, which can usually be solved with some electrical contact cleaner, tightening with a dental pick, and di-electric grease.

Timatt, have you heard the fuel pump at idle when the fuel level is low?

Heath

[timatt]

All right, my brain isn't working yet this morning. I know that MAF= mass air flow sensor, but what is CAS?

Tim

[maxnix]

Crank Angle Sensor.