fastcrxsi90

i just got done installing my hmt setup…and im having a bitch of a time getting it to idle/rev smoothly. basically i installed the turbo and ran it in vacuum with the stock 240cc injectors and everything was peachy. engine has run top notch for years. put on my wideband and it ran high 14 afr at idle and cruising. now that i’ve put on a set of dsm 450cc injectors (all about 2.5 ohms) and changed the tune…it runs like hell.

i can get my idle to run about 14.5-15 afr…and its semi smooth…but its really choppy if you rev it fast with no load, and a little smoother but still shitty if you rev it slowly.

tried a compression test…that was good. when i yanked the plugs, i noticed that #4 was completely covered in black soot…not wet, just really sooty. the other plugs were dirty, but that was probably from trying to get the idle dialed in. put another set of plugs in, let it idle for about 2-3 minutes…same thing, #4 completely covered with soot. i’ve also noticed a loss in vacuum, down from about 20inhg to 15-16 at idle…still goes to about 22-23 when you rev up and let off the gas though.

what im trying to do is first tune vacuum for the 450’s…so i thought that 450-240/450 = about 46% difference in flow (at same pressure). i tried dropping the fuel map (left ignition map stock) about 40% across the board…way too lean…wouldn’t hardly run. i only have to drop about 12% of the fuel to get a 15 afr idle…is that normal? would reving be really choppy even though im basically using the stock fuel map and just scaling the entire thing by a percentage?

fyi, engine is a d16a6, obd0 pr4 ecu (using pm6 fuel/ign. maps), i’m running the newest version of turboedit (2.6.2), and using an lc-1 wideband.

symptoms:

- #4 spark plug gets covered in black soot within minutes of idling.
- only running about 15-16 inhg vacuum at idle (ran close to 20 before injector swap)
- idle is semi smooth, and reving is very choppy

stock timing, stock (pm6) ignition map, 36 psi fuel pressure (40 with hose off), not throwing any codes, o2 sensor is disabled (but ran fine before).

is there a possibility that the injector on #4 is sticking open slightly and that one cylinder running rich makes everything choppy, or am i just crazy the way im setting up the fuel for the 450s? i’ve tried other peoples tunes and they all do the same thing, just seem to run worse…

my next step is to throw the 240s back in to make sure it still runs okay, and maybe i can clean the 450s or buy more and hope i get 4 that work. im kinda lost with this....been doing lots of reading but i cant seem to get it right....

Soccerking3000

i read most fo your post did you put the resistor box in?

fastcrxsi90

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Soccerking3000 &raquo;</TD></TR><TR><TD CLASS="quote">i read most fo your post did you put the resistor box in?</TD></TR></TABLE>

yeah, its obd0 so i've already got a resistor box...


sorry for the long post...cliff notes:

1. engine ran great originally
2. swapped in dsm 450s from egay
3. dropped entire fuel map in vacuum by ~12%
4. idles semi-smooth at ~15 afr, but stumbles horribly when revved
5. covers #4 spark plug in black soot within minutes of idling, but other plugs are fine

injectors are all clicking, they all sound about the same with a stethascope...

anyone have any guesses?

ill try moving that injector to a different cylinder and see if it just moves the "black" plug....

Soccerking3000

does turboedit have individual cylinder trim? what you could do is, swap out the 450's for the 240's and use the individual cylinder trim to add that 46% more fuel back in and get it running. Then go and install the 450's one at a time starting the car up after you swap one 240 for a 450, and then adjust that cylinder back to zero correction since you already have the fuel tables modified for them. That should show you if one of the injectors is bad.

Kind of a pain in the *** but then you'd be certain

fastcrxsi90

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Soccerking3000 &raquo;</TD></TR><TR><TD CLASS="quote">does turboedit have individual cylinder trim?</TD></TR></TABLE>

not that i know of.... otherwise that would be a good idea...

i think im gonna yank them out when i get home...ill reinstall that one questionable injector in another cylinder and see if it still runs shitty....

fastcrxsi90

unbelievable...
i put the 240s back in with the stock maps and it runs great. idles about 12.5 afr and revs like it should.

i cleaned the 450s and nothing really seems to be wrong with them...so i put them back in and ran it with the stock maps thinking it would be running really rich. it ran shitty like before, but with a 14 afr...and now a different injector is making the spark plug turn sooty..... i turned the fuel pressure up to about 45 psi thinking maybe that would help with atomization, but it didnt help at all.

does anyone have any experience with something like this? its not making sense at all.... i just cant tell if the injectors are bad or if im just not tuning the fuel correctly. i shouldnt have to change the ignition map should i? can you tell this is my first turbo setup.................

Soccerking3000

well you did everything right in terms of installation and changing the fuel maps so they work fine. Maybe check the resistance in the dsm injectors compared to the resistance in the stock injectors to see if there is a difference between them, there shouldnt be any, the dsm's should be around 1-2.5 ohms. Maybe send them out to be cleaned and flow checked as well?

0618turbocivic

hey did you find your problem? i had a similar problem, i have turbo setup and ran 240 injectors ran good untill i was able to get dsm 450 cause i only had 3, anyways one day started running like **** with 240's wouldnt be able to go above 0 boost with out going into limp mode, i switched out with another pair of stock 240 and it ran alot better like in beggining, but gas went down, right now im just waiting for my 450's but had a similar problem let me know what happen? cause i will be putting my 450's in soon

fastcrxsi90

i've tried everything that i can think of...i can get a decent idle, i just cant get the car to free rev smoothly. (i havent even been able to road test this yet.) if i give it maybe 5% throttle, it will rev up slowly and smoothly...but if its at idle and i give it a good amount of gas, it just stumbles and shakes and revs up really slowly...it really sounds like crap.

its also wierd that the larger injectors are showing a leaner afr vs. the stock injectors (using the stock maps). thats got me puzzled. what would cause that?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Soccerking3000 &raquo;</TD></TR><TR><TD CLASS="quote">well you did everything right in terms of installation and changing the fuel maps so they work fine. Maybe check the resistance in the dsm injectors compared to the resistance in the stock injectors to see if there is a difference between them, there shouldnt be any, the dsm's should be around 1-2.5 ohms. Maybe send them out to be cleaned and flow checked as well?</TD></TR></TABLE>

the dsm injectors all measure the same resistance...they jump around on my meter between 2.5-2.8 ohms. my original 240 injectors are all about 1.8 ohms...though i dont know what effect that change in resistance would have. thanks for your help so far though...

i just ordered a set of fully cleaned/tested dsm 450 injectors from ebay , so hopefully that will cure my problem.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 0618turbocivic &raquo;</TD></TR><TR><TD CLASS="quote">hey did you find your problem? i had a similar problem, i have turbo setup and ran 240 injectors ran good untill i was able to get dsm 450 cause i only had 3, anyways one day started running like **** with 240's wouldnt be able to go above 0 boost with out going into limp mode, i switched out with another pair of stock 240 and it ran alot better like in beggining, but gas went down, right now im just waiting for my 450's but had a similar problem let me know what happen? cause i will be putting my 450's in soon </TD></TR></TABLE>

i really hope you have better luck than me....

0618turbocivic

i know you said you put in the bigger injectors but it sort of sounds like your not getting enough fuel if you cant rev it up with out putting, did you try adjusting your timing? i had my timing back and when i put my turbo back on i forgot to change timing and it ran like ****, try advancing your timing..

fastcrxsi90

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 0618turbocivic &raquo;</TD></TR><TR><TD CLASS="quote">i know you said you put in the bigger injectors but it sort of sounds like your not getting enough fuel if you cant rev it up with out putting, did you try adjusting your timing? i had my timing back and when i put my turbo back on i forgot to change timing and it ran like ****, try advancing your timing.. </TD></TR></TABLE>

thats whats wierd...with the same injector duration, changing from the 240s to 450s it should run alot richer...but it runs leaner on the wideband. even though the latency for the 450s might be larger, it still seems like it would run too rich. its almost like the fuel must be pooling up and not burning, but i dont know if that would register on the wideband and wouldnt the plugs be wet?

i run stock base timing...16 degrees. ive tried advancing the timing were it idles, and it still doesnt help.

very frustrating....

help me get this piece running good...

0618turbocivic

looks like nice setup try resetting the afc and redoing the settings? reconnect the injector wires for good connection not sure , havent gotten around to do my injectors yet hope u find the problem

0618turbocivic

i know this is off topic but just wondering how you put pics on honda tech? lol just got some pics my car

0xenocron

its possible one injector is bad...send them out to get cleaned and flow balanced...its really not that expensive.

PM me if you need a place thats reliable, not so expensive and only one state away (no its not me doing the cleaning)

BTW...latency on DSM injectors is HUGE. You are going to be somewhere in the 2.0 and greater injector pulsewidth in the idle area with DSM 450s...after about 3800 rpms or so, the effects of latency seem to disappear.

fastcrxsi90

this sucks

i bought another set of cleaned/flow tested dsm 450s and im still having the problem with free reving. its really not as bad as before, but it still bad. when you rev it up you can see vacuum go from ~18 to 0 really fast, and you can watch the tach slowly move up and the engine shakes pretty good. i've tried a few bins so far and they all have to same problem.

i took out the plugs and 3 were coated black and one wasnt as bad. this is opposite to what they looked like before with 1 black and 3 not to bad.

i ran it a few times this week with the stock 240s up to 6 psi (only a t25 and only reved to 5500) and it was strong, ran like stock and ran mid 12 afr throughout the rev range.

i hate to ask, but does anybody see anything terribly wrong with this....
if you have TE here is the bin...http://www.geocities.com/joeyp...4.bin
note that im still only tryuing to get idle, and figure out why it wont free rev...

coneheadsracing

Does turbo edit have the setups for bigger injectors? Like in uber, you change that, and you have to change a few other things... plus it has boost controls, for more fuel, and ignition. All my basemaps, unless a bad chip/burn, have always ran great out of boost. I don't even usualy touch the out of boost portion, other then fine tuning. Not familiar with turbo edit though.

0xenocron

Send me an email with your setup and I'll send you a BIN I know works.

It would really help if you had a wideband on this too.

fastcrxsi90

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by coneheadsracing &raquo;</TD></TR><TR><TD CLASS="quote">Does turbo edit have the setups for bigger injectors? Like in uber, you change that, and you have to change a few other things... plus it has boost controls, for more fuel, and ignition. All my basemaps, unless a bad chip/burn, have always ran great out of boost. I don't even usualy touch the out of boost portion, other then fine tuning. Not familiar with turbo edit though.</TD></TR></TABLE>

yes, it will scale for a number of injector sizes...i just cant get it to run good....

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xenocron &raquo;</TD></TR><TR><TD CLASS="quote">Send me an email with your setup and I'll send you a BIN I know works.

It would really help if you had a wideband on this too.</TD></TR></TABLE>

i sent you an email...thanks for your help...

i have an lc-1 wideband hooked up...with the stock 240 injectors it likes to run around 12.5:1 but with the 450s ive run anywere from 12 to 20 afr and i cant get rid of the free rev problem...
i have some videos of the car idleing...i could put them up if it would help...

jeremydde

Are you sure you aren't starving the 450's by installing them too tightly? Recently I had that problem on a buddy's car where we had to put washers under the fuel rail with the dsm 450 to space it higher. You could be tightening it too low so the injector tips are starving for flow in the fuel rail.

fastcrxsi90

finally figured it out... (knock on wood)
it was my new cleaned/tested injectors. 3 of them covered the plugs with black soot and one didnt. so i tested them with a AA battery while they were pressurized on the rail. all 3 that were running rich dropped pressure almost instantly, and the fourth one took 3-4 times as long to drop pressure in the rail.

so i tested my other 4 450 injectors and picked the one that most closely matched the pressure drop of the good ones...and now the free rev problem is gone. just got a slight hiccup around 2400 or so...awesome

thanks everyone for the suggestions, and thanks to xenocron for taking the time to send me a basemap. fyi, he did an awesome job chipping my pr4 and sending me parts for my pm6...