Hi everyone, i have this dumb problem and its really bothering me. after my car is warm, when i shut it off and its off for about 20-30 min and try to fire it up again, it cranks over for a long time without startin. i try for about three times, pulling the choke, and hitting the gas but holding the pedal all the waydown seems to work. when it finally starts up i get a lot of white or dark gray smoke out of the tail pipe and it smells like gas, my mods and tuff are at my sig, and yes i changed my fuel filter i do have spark and i have 4 psi worth of fuel at the regulator. the car runs great when warmed up its just that time. and when its completely cold and i have to pull the choke all i do is pull the choke, turn the keyso the fuel pump gives fuel for about 7 seconds then it starts up fine.well any info would be good, thanks.

 

How many miles on the engine? Hot issues are often an indication of low compression. Pour a little motor oil down the carb and see if it starts easier when hot. Do a compression test.

 

137,000 miles on the engine, do u really think its low compression, if it is y does it run good?? wouldnt it run sluggishly if it had low comp??

 

sorry but yea this is a good sign of a bad motor. sounds like you have somethin to do this winter! Luckily you didnt buy a car this way like my friend did and they pay for a new motor.

 

o well, this gives me a new reason for a rebuild now besides porting thanks u two.

 

it could be running rich. sounds like it. dark grey blackish smoke. Holding the accelerator means you holding open the intake for air until the air/gas ratio matches and it fires up!

 

Your motor is probably fine. Try this, run a can of seafoam through it to loosen up the apex seals (1 can to 1/8 tank of gas). Then, set your timing (a common source of hot no start issues). Then when attempting to start it when warm, pmup the gas twice then turn the key. Don't use the choke when the motor is warm. My engine has 206k on it and starts just fine...

 

If you still have it, check to see if the hot start assist is still working. Basically it was designed to open the throttle for you when you start a hot motor. If it is not working or was unhooked or removed, you will have the problems you described.

 

yeah i dont have the hot start assist motor, i tried the seafoam and it still happens but the car runs a lot better after the seafoam, thanks kenetsu. i think i found the problem. my vacuum advance lines or hoses are hooked up to the carb wrong, and so far its been starting fine, but its missing that effect from the hot start assist motor, can anyone give me any ideas on wat u guys did to start ur cars up without it when warm??

 

Try pulling the choke 1/2 way out. Hot starts usually need a little extra fuel. Do a compression test and post the #s.

 

ok, trochoid, i tried pouring a little motor oil down the carb after the sea foam and it seemed to start fine, without choke or nothing, but it happens sometimes, i dont know anywhere i can get a comprssion test but mazda dealer, but ill check at my technical school if i can, then ill post, thanks everyone.

 

ok everyone, so i got my compression test today at my school, i did it my self and for 95psi for the front rotor and 85 for the rear rotor, i saw the spec in one of the books and it said85 was the minimum, i think my nubers are pretty good.

 

You should have 3 #s for each rotor. If the 85 in the rear is the combined pressure of all 3 rear combustion chambers, that means the best one is 85 psi and the other 2 are probably lower and under minimum. Sorry, but your #s are not that good in the rear. I would consider a rebuild before parts become more worn.

 

yeah i want to rebuild my engine but, 95 for the front and 85 were just from one of the chambers, i got 95 on upper rotor #1 and 95 on lower part of front rotor, and on the rear i got 85 on upper and 90 on lower. my teacher told me to do it a couple of times and it seemed to go higher everytime, like on the front rotor it hit 100 but 95 was the average, and on the rear rotor it hit 95 but 85 was the average, u know wat i meantrochoid, but if i need a rebuild, then let me know, im dying to rebuild

 

I don't know if a motor on the way out is a good thing or a bad thing...in my opinion its just another excuse to get that motor rebuild that you really want

 

yeah, i think im gonna rebuild it, but whats the worst that can happen if i wait till it has no comp. ?im not going to but i dont have enough yet for a rebuild kit andthe parts