97 I30 starting issues

[4ifreak]

if its 40 degrees or colder it starts great, if above it starts poorly. I changed out all the injectors thinking it had a leak down problem and has 250k on it, all the pintles were broken of the injectors as well, then i did a tune up plugs, ohm tested coils, changed fuel filter, air cleaner, also changed out valve cover gasket and intake gaskets while in there. I have cleaned the maf and throttle body, also unplugged the egr tube going to the intake. I put in a pressure gauge and it seems to only like to prime up to about 30-35 psi with the key on, and will run about the same when it's started, and will spike at about 43 44 psi with vacuum port unplugged. pump will build about 55-60 psi if i pinch the line right after gauge between rail and holds pretty steady for along time. if i just shut the car off with the gauge inline it will bleed down fairly quick when engine cold and seems to hold a little longer engine has been running for a while. The car runs like a clock when started, and even starts good after its been started. It never seem flooded when it does start so im thinking fuel pump or the FPR. I have run several grounds to motor and have cleaned off the CPS with no luck. I have a really hard time hearing the fuel pump run but know it does due to movement of pressure gauge, so i don't know how long it cycles. any help or suggestions would be greatly appreciated. This has been an awesome car up until just lately, best i've owned for a touring car yet. I have been thinking about removing the iac and cleaning but didn't thinks that had much to do with the starting issue at hand. there is a cel but i haven't had a chance to pull it, i think it will be for egr, i recently replaced that part thinking it was failing but now can see why that code came up quite a few months ago. this has been a problem for about 18 months or so, first it started out hardly ever, and now its about always. Thanks Shane

[Ace2cool]

If it's anything like the Z32, (I30 has the VG30, right?) then the FICD (fast idle control device) is built into the IAC and would definitely have something to do with starting. What does the FSM say the fuel pressure is supposed to be? FPR and pump are never out of the question on starting issues.

EDIT: Any CEL or stored ECU codes? If you have access to a code reader, that is?

[4ifreak]

I think its the VD3 but i haven't had to work on this thing enough to know yet. I know on my Chevy van it would crank and crank and crank and maybe you'd get a litle stumble out of it but fuel pressure only would see about 30 psi and i think on the gm's or that on in particular you had to have 43-45 psi behind the injector to get it to spray (open). I just don't get why when it's cold it will start perfect, maybe the spring rate in the fpr is a little higher and that's just enough to get the job done, or maybe it's the fuel is just a little denser?
I just ordered a jdm adjustable fuel pressure regulator and am going to install that and we'll update from there. thanks.

Are the fuel pumps easy to do in the i30? I can't even hear this pump run with clicking that goes on under the hood when the key is cycled.

[4ifreak]

just replaced the fpr and cleaned crank angle sensor up by the crank pulley and it's been starting good for about a week now. also cleaned the sensor plug with spray cleaner and also used die electric grease when plugging it back in. hope this can help someone, these can be a pain to work on when causing these issues.

[flame]

I have an 01 I30 that was starting hard. It would crank a long time (5-7 sec) before reluctantly firing up. It would run well after starting, and would fire right back up if it didnt sit too long. If it sat for 10 minutes the issue would rear its ugly head. I replaced the fuel pressure regulator, and the fuel pressure damper and the issue seems to have disappered..