hey fellas, i got an 84 svo (stock as far as i know) that i just bought and im having a problem with it spark knocking and i need some help! is there anything that any of you can think of? thanks.
it knocks at about 3k and above in accleration and i beleve it knocks in the same range in deceleration, dont know the timing (just bought the car), 93 octane, autolight plugs (not plat), msd wires, and it has a fairly new distributor but i dont know how old or new it is, looks to be a stock replacement. 120k to 125k miles on the car.
Spark knock/detonation is not possible on decel because the injectors are shut off and there is no load on the engine. This would indicate an external rattle such as the cat converter shield.
3k is about when the boost kicks in which is "typical" of a time for detonation. If that is indeed what it is, it should go away if base timing is reduced. Stock timing is 10 degrees BTDC when the spout connector is removed.
well the car has no cat. but the noise that i hear sounds like marbles in a can, but its kinda a loud noise and it seems to be at the back of the engine, do you think it could be something to do with my turbo or wastegate? i hope it has nothing to do with valve issues and if so then i might as well put a performance cam in right.... thanks for all your help.
brandon
i have a 93 n/a 2.3 with the same problem, it didnt start until it got really cold outside, can it be sucking in too much cold air? i would really like to fix this as it is an annoying/embarassing sound, and would really like to know whats causing it.
Sounds like detonation to me...as stated, check the timing. If the timing is OK, odds are it's either a weak fuel pump, plugged fuel filter, dirty injectors, or a extremely carbon-filled engine...
hey fellas, just got back from harris racing in concord, nc (dont know if yall have heard of them) but i was told that the car had 30lb injectors in it and i also remember the previous owner telling me he had replaced the injectors in the car not to long ago. they said that they figured it would just need a good tune up, do yall suggest i replace the fuel filter and pump as well? and also if i was to replace the fuel pump what pump should i put in it?
I just talked to harris racing on the phone yesterday...they've got a car in the shop getting all of my "goodies" installed...
I still say don't spend any money until you check the timing. It is most likely the cause and is like a 5 minute fix...
You can test the fuel pump to see if it is the problem. You'd need to replace the filter first though as it would act the same as a bad pump. The filter is like 8 bux from the parts store. Just checking fuel pressure under boost would tell if it's good or not. It should raise fuel pressure 1psi for every 1psi of boost. If it starts dropping off under boost, it's getting weak.
Just thought of one more thing that could cause your problem...platinum plugs.
well actually im gonna replace the filter anyway just to know that i have a good filter in the car and i talked to harris racing today and ima have the dyno man tune the car (if he can) and then go from there. and i also just put in new autolight plugs (non-plats) so that shouldnt be my problem. ill keep u guys posted.
Pull those plugs back out and cut the gap down to .030"...they come out of the box with about .042" which is WAY too much and the spark will blow out under boost.
well i think i got my spark knock fixed. the timing was set at 20 degrees btdc. i took the car to a guy at a local ford dealership and he fixed it in about 5 minutes. it runs alot smoother and quieter.... so im happy!!!