I am having some problems in starting up the car with warm/hot engine, i have to give it some light gas on the pedal, if not the cars starts but stalls immediately
usually it takes three times to start it without that light gas, with, no problem but have to keep it more or less at 2000' for some seconds
i also noticed thata the aws now puts the car at 2200/2500 revs on cold engine, instead onf 3000 as before
i got brand new oem plugs but nothing changed
any suggestion?
thanx

 

Check your compression so you can rule out a possible worn engine. My warm start problem was solved by replacing my burnt out leading coil, but everyones seems to be a little different. How warm is the car on these hot starts? If the engine is heat soaked to the point of rediculus numbers (water and air temps) what you are describing is pretty normal from my experiences. Do a search for hot or warm starts and you should get a ton of threads describing what it could be (a bad FPR is a possibility).

As far as the AWS, that's what my car does too (also just changed the plugs). I think those numbers are fairly common.

 

In fact this happens only if i leave the car standing
it does not happen for ex. if i stop and immediately turn on again
it seems it is a problem in the engine soaking heat from turbos/radiator even if outside is pretty cold (1C )

 

maybe FPR solenoid valve???

It is suppose to aid in hot starts, and maybe it's worn out...although I've removed mine and I have no problems. So Maybe since yours is still in the circuit the FPR isn't seeing the the proper pressure to get the car started?? .....if the the SV isn't working.....just a thought.

 

What do you guys mean with FPR?
i did a search but problems presented in these threads are different from mine, my car should have a good compression because it has a 12000 miles-or-so Mazda reman engine, but in fact i never did the test.
The car runs, idles, and boost really perfectly, when cold starst up really perfectly without touching the pedal.
Only when you leave it for, let's say, 5 to 40 min alone it will start but stalls immediately, this takes always three times, not more not less, to start and run correctly without touching the pedal, if i stay a little bit on the pedal it starts immediately, the revs jump a second or two and the idles perfectly.
May this be connected to the other weird problem i am having? see the thread "could not go over 160 Km/h"

 

Fuel Pressure Regulator Solenoid Valve raises the fuel pressure on a hot start to make it easier to start.

And there's only one way to test it that I know of...take the UIM off, and dig thru the rats nest. It's the solenoid valve closest to the firewall and connects directly to the FPR.

What you are describing sounds just like what would happen IF that solenoid would fail...car gets heat soaked and has trouble starting. BUT like I said, I've removed mine and the FPR seeing pressure straight from the LIM and has no problems starting EVER.

 

****
i thought about it
that makes sense also with the other problem
the REAL problem is that our European Fd are different and getting to the FPR is very hard, and the FPR is double (they said it to me, i've never seen it even removing the UIM)
****
think i'll have to get it to the Mazda service

 

When I asked my mechanic about that a while ago, he said give it a bit of gass (BTW, I had low compression)...another way around it is to set the fans on for c. 2 min when you stop...this should stop the problem...in any case, you should do this especially if the car is so hot

 

This will cool the coolant in the radiator and somewhat the bay...not going to discuss that....

Heak soak will set in regardless and the same issue with starting will remain.