this might be a stupid question so dont hate me for it but, i was told by some of the other local tuners seeing as i am new to this my self that my car was running a little rich i drive a 94 non-vtech 5-speed and i was wonderin if u could tell me how i could quite possibly fix that or if that is a take it to the shop thing....also if any1 knows where i can get my hands on a vtech for resonable that would be good too thx

 

easiest way to tell if ur running rich is check ur tailpipes and bumper for black residue, soot really. if its there u may be running rich but preludes are notorious for running rich, so probably nothing is wrong.
as far as vtec, yes vtec. not vtech. its not something u can just get. You would have to purchase a whole new engine and have it installed, since your are admittedly a noob. would cost anywhere from 1500-3000 for engine swap package and another 1000 or so for install. btw nothing wrong with SI prelude, still fun to drive, im sorry if u have the plain old S, those things just are no fun.

 

search and you will find.

hmotorsonline for h22s VTEC (no h dude)

and you can lean out the a/f ratio by buying a standalone/programable ecu/piggy back

and you should consider buying them in that order. but do a search on those topics and it will get you started

 

if your car is running rich you: will have black **** around the exhaust opening, check your spark plugs (search or look in a haynes or whatever to see how spark plugs will look if the engine is running rich or lean or too hot etc...), will have high hydrocarbons (HC) during a smog test, gas mileage will be lower than normal, higher than normal carbon buildup on pistons or in exhaust or egr or combustion chambers

if your car is still stock, most likely if you are running rich 1 or more sensors are not working correctly, check or have checked o2, iat, and map sensors first based on the instructions in the helms/service manual, if those are good check the other sensors that could affect it (obviously things like oil pressure and similar sensors will not affect it...), also if you have access to another ecu, you could try using that as there could be a malfunction in the ecu circuitry

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by soccmid1587 &raquo;</TD></TR><TR><TD CLASS="quote">,im sorry if u have the plain old S, those things just are no fun.</TD></TR></TABLE>

x2

 

I would personally get a DSO (Digital Storage Oscilloscope) and look at the O2 sensor first... to verify if you're running a rich mixture...

 

Is your prelude stock or does it have any modifications, (intake, exhaust, etc)? All vtec motors are notorious for running a tad richer when vtec is engaged.

 

it's not v-tec.

 

sry for so long to reply i been gone but like i said im just a noob i dont no what it is as far as SI S but i know its not a VTEC but i have an exhaust a 3A Racing Muffler and i think i THINK it has a high performance cam on it bc at around 3500 performance starts to pick up alot but yeah there is alot of soot in the muffler its self and for some reason the 4th spark plugwire keeps unseating itself kinda like its backing itself out but yeah thats what i know thx for the help so far though