okay so here's the problem. i was boosting 10psi before and everything was fine. i had decided(well friends on here decided for me) to turn the boost up and tune with Boost Comp. on the EMS which allows me to turn the boost level to any desired level and the EMS will automatically 'learn' and adjust the a/f level to 11.5:1 which is what i have my a/f set at. anyway, this was all done on the dyno...so after setting the boost comp, we turned the boost up to 14 psi and slowly watched the a/f as it stayed pretty steady at 11:1-11.7:1. as soon as we knew the boost comp was working we did a pull and from 5.5k rpm and on it started to misfire like crazy!! a/f was all good and pretty flat. took out the spark plugs and put brand new ones in gapped at .028. let the car cool down for about 10 min and tried again...still the same thing!! checked wiring, vacuum, grounds, etc...nothing. regapped plugs to .035 and still the same problem. tried adding in more fuel/taking out fuel....advancing/retarding timing...nothing helped! so now i'm stuck with this problem and can't boost past 11 psi without this happening.!

boost experts/problem solvers...now is the time i desperately need your help!!

another thing...11 psi and below...it runs fine, it's only when we start boosting more that it starts to do this. i tried street tuning it tonight with no success at all. the next thing i'm gonna do is install an MSD SCI ignition system. if that doesn't work...i'm pulling the head to see if it's a blown head gasket. compression check today looked like this:

cylinder 1 - 180
cylinder 2 - 175
cylinder 3 - 180
cylinder 4 - 185

 

here is what the dyno chart looked like. sorry i couldn't find the chart with the a/f on it but trust me...a/f is fine. shane(the tuner) said if it wasn't misfiring it would of made a lot more power...man...that really sucked ***** for me

 

anyone?? oh well, i'll check my thread again when everyone is up and has gone to church and back. i'll be taking my life/health license course so i'll be busy. and all my buddies will be out at the track on sportcompact day tomorrow running their cars all day!!! FREAK!! why the hell do i always end up with the bad luck?

 

damn...anyone??

 

my dyno sheet looks the exact same way with chops and everything but only making just above 200 whp. i am misfiring too. my shop says it could be the cap or rotor on the dist, but hell, i have no idea.

 

Possibly gap your plugs smaller yet. Sounds like it could be blowing the spark out.

Try a .025 or .026 gap and see if it continues to do it.

 

install that MSD asap. Your dyno looks just like my friends at 9 psi. blowing out the flame.

 

what map sensor are you using?

 

what does it mean to gap the spark plug down or up... how is this done and how could this be measure??? or is this talkin about the gap on the spark plug??

 

What heat range plugs are you using? 7s, 8s, 9s?

 

are you using the stock map sensor or what? if you are then theres your problem

 

u need a hondata 3 bar sensor

 

DON'T pull your head to check for a blown headgasket... that is NOT the problem!

You DON'T need a GM 3 BAR, that is not the problem.

I have been fighting this issue on two cars VERY recently. A few things to try, first of all if you are having a misfire issue at high boost, tighten the plug gap, don't widen it. See if that helps, try .025"... don't go much tighter than that if possible.

Another thing to check is your plug wires. Check the resistance across each of your plug wires, the longer ones should measure more resistance. You will probably see around 5-7 Ohms, if you have a whole lot more than that then replace that wire.

Next, try NGK plugs part number: R5672A-10. -Good plugs. I usually run NGK part number 2975 which is a zfr7f-11, and gap them around .033", but on cars that are misfiring I have gapped them as tight as .024"... the R5672A-10 solved the ignition issue on a misfiring car recently, which still has me stumped because we were replacing Denso Iridiums. It worked though. Good luck and LET US KNOW HOW YOU FIX THIS ISSUE for future reference.

 

does it back fire a lot? seems like the high cam is doo-doo

 

alrighty, i thought that maybe it was my 3bar map as well...today i switched over to a new GM 3Bar MAP and it did the same exact thing. my plugs are 2 step colder...but i forgot the stock number. at the moment they're gapped at .028. i tried adding race gas today as well and it still did the same thing...man this really sucks. next thing to do is order those R5672A-10 and try those out and install the MSD SCI and see if that changes anything.

anyway...the reason why i wanted to take the head off and take a look is because on the dyno after hard runs, i see a ton of air bubbles being pushed into the coolent resivour and it just keeps on bubbling up until the motor cools down. also i've noticed that on my laptop my EMS reads 210* coolent temp, and so does my autometer coolent temp gauge. on my stock gauge that's close to half...i think 2/5 if that helps. man...i really need to solve this issue...

i'll also try swapping out the spark plug wires tomorrow and see if that helps as well. thanks for the help guys...if anyone has anymore suggestions please let me know because i need to try everything to get this baby running right.


-sherman

 

I just had the same problem at the dyno, except I am fine on my street tune (15psi) but start misfiring at 18+ on c16. Was fine a month ago at 19psi, but I wanted to retune with my since upgraded 3"downpipe exhaust (replaced my 2 1/2 set up). We turned it back down to 15psi and no problems I have a msd blaster (external) coil and 2 step colder plugs.

With my old 2 1/2 exhaust set up I made 292 whp @ 15psi (on mustang dyno) and 331whp at 19psi. This time it made 310whp @15 psi and due to the misfiring, I couldn't get a race tune at more boost...
I am suspecting my plug wires (at least hoping), and any other info from you turbo gurus would be helpful!

 

I have worked on 2 B-series engines on AEM EMS recently, that were both reading upwards of 215 degrees fahrenheit coolant temps! Seems quite a bit high to me too, but they are both running strong, and have been doing so for over 3 months. If your compression is consistent then don't worry about your coolant overflow. It's just 'cause you're getting a little hot.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hondaddict &raquo;</TD></TR><TR><TD CLASS="quote">I have worked on 2 B-series engines on AEM EMS recently, that were both reading upwards of 215 degrees fahrenheit coolant temps! Seems quite a bit high to me too, but they are both running strong, and have been doing so for over 3 months. If your compression is consistent then don't worry about your coolant overflow. It's just 'cause you're getting a little hot.</TD></TR></TABLE>


thanks Hondaddict. yeah i was getting worried because i talked to some guys that i pulled(EVO 8, EVO 8 RS, and RX-7) last week on the highway after midnight(only a single run to 130mph...lasted like 5 seconds or so) and they said when i took off and they were trying to catch me, i was shooting out coolent all over their windshields. that worried me and i checked my compression which seems fine and my coolent level doesn't seem to get any lower either. anyway, i got some new spark plug wires so i'm gonna try those tonight and see what happens.

 

okay...problem solved!!

swapped in regular NGK plugs 2 step colder...for my V-POWER NGK plugs. retained the .028 gap...

no more misfire!!! OMFG!! it feels so good to not have that boggin feeling!! next to go on will be the MSD so i can largen the gaps a little more.

thanks guys for all the help.

 

which plug did you go with?

 

i swapped from the V-POWER ZFR7F-11


to the standard BKR7ES-11 which NGK said were for GSR motors???


notice how the firing end on the V-Power plug is longer. I suspected that my spark was "blown" out because of this and decided to try out the standard plugs due to the shorter firing end. the standard BKR7ES-11 was gapped to .028 and solved all my misfiring issues. it feels good to have a smooth power curve again.



Modified by shermanyang at 6:08 AM 8/5/2004

 

sorry to thread jack but what do u recommened(spark plugs) for a d16y8 motor?

 

i would just go with 2-step colder standard plugs for all boosted applications. i'm not sure what the part number is for your motor...sorry i couldn't help you there.

 

Awesome! Thanks for getting back to us. Good to know that your problem is solved. Now lets see some new dyno numbers!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hondaddict &raquo;</TD></TR><TR><TD CLASS="quote">Awesome! Thanks for getting back to us. Good to know that your problem is solved. Now lets see some new dyno numbers!</TD></TR></TABLE>


no problem! i just hope that i was able to help some other peeps on here by solving my own issue. and thanks for pointing me into the right direction Hondaddict.

i would hit up the dyno again...but they're booked till the end of this month now...i was able to get my car tuned last time because my buddy on here went to get his car tuned and ended up frying his distributor on the dyno 5 min after getting on it. i'm sure they would squeeze me in...but i really have to get my head built up and ready before i do anymore tuning. i'll post up numbers when i do get it retuned again.