My latest nightmare, and the one topic I never wanted to have to post.

engine setup:
b16 freshly rebuilt with new 9:1 pistons, rods, bearings etc.
good compression

fuel setup:
mitsu evo peak and hold 560cc injectors with resistor box
walbro 190 pump, b&m fpr set to 42 psi.

electrical setup:
s300 hondata in p28 ecu, obd1 conversion, motorola 2.5bar map, new dist. king dizzy.

Problem:
no cel, using stock p30 map with map sensor set and injectors set to 560cc, crank engine, it fires and dies right away, gets to about 325rpm on the datalog but dies.


Plugs are wet, I am getting spark, compression good, fuel pressure is set to 42 as the pump primes and stays steady, but drops to ~20ish while cranking.
I'm stumped and I am afraid of washing out my new rings
Please help

 

why did you change distributor? Old one bad?I remmeber people having problems with rebuilt dist king units before.

double check your converson harness?

Is there a way you could use your stock ecu without the conersion harness just to see if it will turn on? with stock injectors maybe?

 

Did you rescale for the injectors? Sounds like your flooding the engine.

 

new distributor is for the obd conversion. as far as i can tell the harness is pinned correctly all stock stuff is long gone.

i went into parameters> fuel trim> current injector size : 560cc and update the ecu is that correct ?
i agree it does seem to be flooding it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by racin_jayson &raquo;</TD></TR><TR><TD CLASS="quote">new distributor is for the obd conversion. as far as i can tell the harness is pinned correctly all stock stuff is long gone.

i went into parameters&gt; fuel trim&gt; current injector size : 560cc and update the ecu is that correct ?
i agree it does seem to be flooding it. </TD></TR></TABLE>

You could always try reverting to stock map sensor and the stock injectors to get it to fire. If not I would atleast start with the stock map sensor just to get the motor going.

 

play with the crank, post fuel, and overall fuel trim and eventually it should run alright. Make sure you have a wideband. If you can get a tuner to come to your house then do it.

 

I could try putting the stock map back on, but the stock injectors are gonzo.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">play with the crank, post fuel, and overall fuel trim and eventually it should run alright. Make sure you have a wideband. If you can get a tuner to come to your house then do it. </TD></TR></TABLE>

I have tried adjusting the cranking trim +/- 15% nothing helps, I cant have a tuner come to my house I live 100 miles from the city, I need it to actually start first before I can pay someone to tune it.

 

yea sometimes the injector scaling doesn't really work. you'll have to play with the s300 a little. try using 660's or so for the injector scale. it might work. with my 1600's i use the scale value for some 880's to get it to idle right

 

try adjusting the post trim. Can you give it gas until post fuel is over to see how much fuel it is getting after that? Honestly you really need a wideband.

 

why would the post trim help? the engine has not started yet, I could sit here and mess with this for hours but I will just end up washing out the rings and wasting a good engine.

this is kind of a catch 22, i could try different things at the expense of killing the engine or I can do nothing and have a 2000lb paperweight. This is brutal.

I just rechecked all my distributor wiring, next I'll try the stock map sensor.

 

def pays to have a wideband

 

did a bit more research and it seems like my injectors reputedly flow a lot more than rated, more like 600-625cc, so I will try redoing the fuel trim for that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by racin_jayson &raquo;</TD></TR><TR><TD CLASS="quote">did a bit more research and it seems like my injectors reputedly flow a lot more than rated, more like 600-625cc, so I will try redoing the fuel trim for that.</TD></TR></TABLE>

Do that and seriously put in the stock map sensor just for starting this thing up. I have had more than a few bad 2.5 bar map sensors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93turbo16 &raquo;</TD></TR><TR><TD CLASS="quote">

Do that and seriously put in the stock map sensor just for starting this thing up. I have had more than a few bad 2.5 bar map sensors.</TD></TR></TABLE>
yea that is the main thing. Almost sounds like the map sensor readings could be way out of whack. Are you datalogging to make sure its reading correct?

Post fuel is how long its adding additional fuel after startup to keep the engine running. If you are getting too much it might bog down bad and die, but more than likely the main scaling is off. A wideband is the important thing though. Who knows how its running exactly without that.

 

The distributor pinned correctly, I know the distributor kings have different colors. Also what kind of jumper harness are you using, if you are using one. Reason I ask, we had a knock off here not to long ago that was pinned wrong causing issues.

 

Got it running, thanks for everyones help

rundown:
-set my injectors to 620cc (the evo 560's approximate flow rating at 43 psi)
-took 20% fuel out across the whole low speed map.
-installed oem map sensor

it fired up right away and ran a little rough...
as per the advice of my tuner I played with my fuel map until I got the o2 sensor voltage to switch rapidly between .1 and .8 volts (aproximate to 14.7:1 afr) which required me pulling another 12% fuel out.
I know I should have a wideband but I did the best i could with the narrow band o2.
The plugs look good and clean.

Best of all, no oil leaks or explosions, however i do hear a weird whining sound from the timing belt area when it revs....kind of like a supercharger whine, I don't remember that.

I'm thinking I might get myself a gm 3bar map as I now have very little faith in the tiny little motorola one that I have but dont know if it works.

 

had this issue with my d16y7 bottom and y8 head. I didnt upload my base map tune to the ecu, once i figured that out i still had issues with idle and cranking, AFRS would sit WAY to rich especially when reving in neutral so i took fuel out cuz it would die out declining rpms. Pretty much the engine was getting flooded once i fixed the rich situation i had to also mess with the IACV on hondata once playing with how much the IACV increases or decreases i got it to sit at 14.3-14.7 AFRS and was successful at keeping the engine alive after reving. Hopefully someone will come across this and try it out even tho this post was from way back then. Good luck

 

This is called TUNING. Is there any reason why, on your first post in this forum, you would necro-bump a seventeen year old dead thread ?

 

lol 15 year old thread! If bro hasn't gotten his car working by now 💀💀💀