quick question, i have a small problem

[Krylonking]

OK when i first start my rb20 in the mornings , it starts up great , but if i get on it after starting it , it sounds like it rapidly backfires in the higher rpms , its kind of like popcorn popper sound , but as long as i drive it normal or let it warm up properly it runs great , it doenst seem like a major isue , just curious if anyone would know what would cause that

[krayton]

let me try this one.

your car starts up its running rich.

or wait, its cold, so its putting in more fuel?

then when u try to gun it its cold and its drowning itself in fuel basically. thus the popcorn type stuff.

i get the popcorn sound when i tune my car to rich.

hopefully thats right. someone else wanna chime in with a better explanation or just say im wrong?

[Ramius83]

Mine did this when my timing was off. Check your timing and get back with us.

[silent dave]

its just running rich when the motor is cold, it normal at startup. you shouldn't be getting on it until the motor is warmed up anyways, it'll live longer.

[Ramius83]

That is what I thought as well, since my Maxima did the same thing. But sure enough, even on colder days after I checked/adjusted my timing, that problem is basically non-existent now. Unknowingly, the car was at 10 degrees timing when I installed it and I had this VERY bad start-up (or warm-up) period. But ever since I adjusted the timing back to the recommended 20 degrees, everything is fine now and I no longer have really bad back-firing and no power during warm-up.

However, I do agree with you 100%. You should NOT be getting on the throttle until you are up to normal operating temperature. By this time, the oil is nice and runny and will properly cover the surfaces and act the way it is supposed to, as opposed to it being thick and sludgy at start-up.

[Slo_240sx]

I just got my car running and had the very rapid popcorn noise also. It sounded like it was detonating way high in rpms. My timing was advanced way forward.. oops... Kicked it back a bit to 20 and runs like crazy.

Listen to everyone, they know what they are talking about. I'm too lazy to retype what everyone else just posted.-Alex