you will eventually need a glow plug wrench because glow plugs do go bad. you will eventually have to change it out anyway.
but like i said, it will stay running with the ignitor on it because at that point the glow plug is glowing red hot and allowing it to burn the fuel. if it is too rich, the compression of the engine can not burn the fuel without the glow plug being "lit up".
the glow plug will either light up or it won't so if the engine will run, the glow plug is working.
if the glow plug is bad, the engine will not run at all.
i may be wrong but it sounds to me like it's running way too rich.
do you have a way to check the engine temp? engine temp will tell you if it is too rich or too lean.
this is what worked for me when i broke my engine in because at first i had the same problem that you are talking about:
turn the lsn (the one that's on the carb by where the fuel line goes in) in until it stops (do not over tighten it). back it out 3 full turns.
set the hsn (the one on the side of the carb by the linkage) so that the screw head is flush with the collar that it screws into. set your idle screw so there is a 1 mm gap in the carb. (have your radio and the car turned on when you do this. set your throttle trim on the radio to 0) take the air filter out and look into the carb. on the carb barrel you will see a hole in it. this is where the 1 mm gap should be.
when you are breaking in your engine you want it to run rich because the extra fuel helps lubricate the new piston and sleeve. it probably will not sit there and idle for the full tank of fuel. you WILL have to bump the throttle now & then to keep the engine from loading up with fuel.
if i were you, i would invest in the t wrench and a few new glow plugs because you will need them eventually. actually, the glow plug that comes in the engine isn't the best anyway, and going with a different brand is a good idea. if you have the vx 18, you can run the OS A3 glow plugs in it.
running a nitro r/c is ALOT different than running an electric r/c. you have to be fairly mechanical and you must have knowledge on how the engine works. you must also be familiar with tuning carbs. because you will have to tune, re-tune and re-tune some more of the weather changes.
there is alot more maintanace and set up running a nitro car. it isn't like you can fuel it up, pull the starter and start running it every time.
they are finiky and slight changes in weather will have you re-tuning the carb. to make it run right.
1/2 the fun is getting it to run right.
i have noticed tho with mine, now that i have ran 3/4 of a gallon of fuel through it, and the weather is somewhat stable now, i don't have to rte-tune it every time i run it.
eventually it will stay tuned, but it may need a tweak or 2 here and there on occasion.