i have a d15b7 with a t3. rc 310cc, my fuel pressure regulator has been replaced, so has my fuel filter. i notice that after i start my car the aem uego goes rich like 12.5 and the more the car warms up the more it starts to lean out until it just girks and bucks because of being so lean. It really starts doing it after i do a good pull of 7psi, no cel or anything the car will idle just fine at 675rpm's. my spark is all fine and my plugs are gaped to .030.

the car started doing it like 4 months ago and has just started getting really bad. I barrowed a fuel pressure gauge from work and hooked it up when i started the car it read 36psi on the gauge so i taped it to my window and drove around, i did a pull and it started dropping until i got home it was at a 31psi. now my fuel pump is stock along with the motor thats in the car and has 187,000 miles on it. Honda recommends 40psi. i am looking at purchasing a walbro 255

please help

 

anyone? i have never gotten a reply on this website

 

are you trying to buy a walbro with this thread or asking why your car is doing this?

 

Buying a walbro 255 will be a good idea, but i think it might be your 310's. I would go with rc 440's or dsm 450's if i were you.

 

the rc's were brand new when i baught them 6 months ago. im not looking to buy a fuel pump from my post just why my car is just all of a sudden acting like this. it was running fine for the first 2 months then started doing this. then it went away and now has come back pretty good and is bugging the crap out of me

 

Im not saying that they are old or anything, but around 7 psi they are maxed out and your car will run lean. Is your ecu chipped?

 

no i am running a safc-2 and they are leaned out about 39% while cruising and 21% under full boost. i would love to get my ecu chipped but i would have to pay someone to do it. and its looking about 400 for a chrome pro full chip and tune. being in high school i don't have a lot of money

 

I hear ya, i got mine chipped for 50 bucks locally on crome and a basemap. But my build is almost finished so im going to have to get it tuned. Try to riching them up a little bit, i dont understand why if they were fine for 2 months but now your car is running lean.

 

1: check your spark plugs (i would say just replace them. gap to .030 as you are doing and make sure you're running the BKR7E's)

2: you need to get your AEM wideband recalibrated. if it's reading 12.5 and your car is leaning out, something is wrong.

3: 310's might be ok for your setup (but in my opinion, they are a bit small. you might want to replace them for some biggers ones or at least check to make sure they are flowing correctly) also make sure you have the saturated ones, not peak and hold.

4: safc sucks. it'll increase your timing just installing it. so be very careful. i would rather suggest you run fmu than safc. if you want to keep your safc, have someone tune with it. it's not that much harder than chip programs like crome and hondata.

air/fuel ratios don't kill motors, timing is what does.

 

the aem reads 12.5 while cruising and the car runs perfactly fine but then the gauge starts to go lean until its pegged lean then it starts to chug and buck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by riceburner700 &raquo;</TD></TR><TR><TD CLASS="quote">no i am running a safc-2 and they are leaned out about 39% while cruising and 21% under full boost. i would love to get my ecu chipped but i would have to pay someone to do it. and its looking about 400 for a chrome pro full chip and tune. being in high school i don't have a lot of money</TD></TR></TABLE>


So you are saying you are running 7 lbs, 310cc injectors, and an SAFC hack with 21% pulled out of the injectors at WOT and all this on a stock pump?


If so, I can help you out here man, first off, 21% out of a 310 (which is entirely too small, I run them in my NA car and they aren't big enough) is only 244cc all things being equal and that's 4cc higher than a stock honda injector.

Second, pulling that much fuel out without using an MSD BTM is advancing the crap out of you timing and causing some severe detonation wich is what the bucking you are feeling is.

Third, a stock fuel pump is not going to be able to support that, maybe when brand new, but not after this many years of use and probably ran on fumes 200+ times causing the pump to get so hot it's almost boiling.

Now you say you are in High school and can't afford a 400 dollar chip and tune, then I ask you this, can you afford another motor when that one lets go? In all honesty, I would do this, sell the VAFC, Wideband, and RC 310's, buy a set of DSM 450's and then have your ecu chipped and tuned profesionally and enjoy driving the car because then it will live.

 

Ok i am not as poor as most high school students. but i am gonna start saving for a chrome base map and a tune, shouldn't take to long. im buying a walbro 255 fuel pump soon. and i am just gonna get some rc 440cc's, i found some decently priced local.

i have one question on the SAFC advancing my timing. exsactly how much does it advance my timing?

 

It really all depends on the amount of fuel you remove, the more you take out, the more it advances. It's one of the unfortunate side effects of tricking the map sensor on fuel delivery.