beecee18

Hey honda tech my first post so be nice, although constructive critisism is my friend.

Helping a friend with a swap in a 91si hatch.
The car was working fine with its former setup:
preOBD1 ls engine stock, turbocharged,
P28 ecu, with vtec disabled, and o2 disabled,
older OBD0-OBD1 ecu jumper(almost positive Locash)
OBD1 LS distributor using a jumper also
walbro 255, dsm injectors using the resistor box.
This setup worked flawlessly, and actually made impressive numbers on the dyno, but the owner wanted to do an all motor setup since the 4 year old LS started to burn oil, so on to the new.

B20Vtec using B20B block
RS machine ITR 84.5
eagle rods
ITR water and oil pump
golder eagle sandwitch and gasket kit
Bisi header
Skunk pro mani w/skunk billet 70mm TB
ARP headstuds (B18C)
Early B16A cylinder head
skunk retainers and springs
BCIV cams
skunk gears
aem FPR and rail
no port
slight deck on block and slight mill on head
P30 ecu, and P72 ecu, OBD1 injectors from integra

I assembeled the engine according to 94-95 integra gsr service manual, and our plans were to use the existing jumper and make a new subharness for the jumper which i did. I also changed all sensor connectors to the OBD1 style gray clip exept the main shock tower ones. We have a P30 Jdm box, and stock OBD1 injectors from an integra for startup. I used the gray clip connector to fuse all resistor box wires together for the higher voltage we will be needing for the OBD1 injectors as per rywires instructions.
To make a long story short when going to make the subharness i could not find the right instructions to do the harness, cause i would trace say the vtec wire to the correct pin on jumper and the color told to connect was wrong. After research i came across some instructions from locash racing that the colors for the subharness were correct. Also used his dizzy jumper to find out that the crank, tdc, and cam sensors were not wired color to color, basicly the TDC, and cam were swapped, I figured they changed this later on to make the dizzy wiring color to color and easier.
All the work is done, fluids in, and ready to start,
but no start.
It sometimes starts to stumble and fires quickly but then does not stay running at all.
Have spark (bright orange and a nice strong arch)
I have the check engine light wired to a switch using one of the extra grounds from the subharness as the other end.
I have unplugged the intake air sensor and it did give me a 10 , but when switched off the engine light stays illuminated with no stored code when switched to check codes.

The service manual tells me that its a short in SES connector(possibly the crappy aftermarket switch or the ground im using)

Ive already completed troubleshooting via service flowcharts the injectors
12V and correct ohms
FI relay cycles the pump for 2000ms then shuts of after with nice positive clicks.
But when troubleshooting the pump service manual states pump should show 12v during 2000ms prime, and 10v during starting
my tests net 8V during prime, and a little over 4V during startup, roughly half the voltage, also fuel pressure seems to bleed off after 10 min or so.
I also checked for flow via manuals intructions out the fuel return from FPR and all seems well.
bottom line is ive heard maybe half a hundred or more 255's in various japanese cars and this one does sound slow and weak.

Tomorrow im gonna flow chart the SES light remaining illuminated with no stored code found in the ecu troubleshooting section and try to find a short.
Everything is to the correct pin and to the book. expecially knowing it worked fine in the older setup
(although the owner was using rywire jumper instructions to wire engine light which is completely incorrect for this jumper so who knows if there was troublecodes)
Also I know this is not by the books but i wanted to see if injectors were spraying so i took all sparkplugs out and told buddy to turn over a few times 5 seconds each and used flashlight down the wells to see any physical signs of fuel(mist, spray,ect.) and seen nothing. but some has went into the chamber but not much, can barley smell it after removing plugs after trying to start it multiple times
It is so inline with a no fuel condition from what I can tell but I need the feedback as I have not toyed with a Honda since 2003. And it seems you need to firebomb these cars just to get an engine light out of them, or maybe smash sensors with a hammer.
Any questions and feedback is muchly appreciated.
The owner can chime in if needed,
Thanks in advance.

spoon93

Anyone?

jdm_h22

Do you hear the fuel pump prime at START position?
Have you tried providing fuel via throttle body? (aka starting fluid)
If you can prolong the engine's run time with starting fluid, chances are it a fuel/pump/injector related issue.

Have you double checked your cam/crank timing? Very important

Definitely start with the basics.

spoon93

The cam and crank timing is not dead nuts on but what I beleive is that it can't be dead on due to the mill and deck of the block is this right? Or should it be dead on I mean it's pretty close

beecee18

I agree, Ill put some fuel in a spray bottle and juice the TB to see what happens, Now the cam and crank timing are really close, when gears are at tdc and side lines line up perfectly the crank mark is just a **** hair towards the front of the car of the timing line on the pump and plastic.
fuel pump is pretty new,
injectors are from a neighboring honda buddy that tends not to keep junk around but ?
we have 1 P30 ecu with a disrtibutor
and a known good usdm P72 ecu with its distributor from same bone stock care for testing.

I still think its the crank sensor not firing the injectors but after today i should know more but any feedback or someone who has expeirenced alike issues please chime in.

beecee18

And yes sorry,
the fuel pump gives me the 2 sec prime, and runs when trying to start, just seems at to low of voltage.
I have jumped the fi relay harness to run the pump continuously and tried to start also but same thing no dice.
the only other set of injectors we have is a set of rc370's that i would prefer not to run stock ecu without tune but for testing porposes would this be bad.

The engine block was already assembeled and ran by the person who sold it to the owner for about 3,000 miles, so the rings have already broken in, so im not so worried about borewashing, we have aem wideband at our needs ready to give us feedback on our afr's

jdm_h22

As far as injectors, typically it's not going to be the injector itself that is bad.
Granted, there are cases where injectors are at fault, but usually the issue lies in wiring. That is, providing signal TO the injectors.

You'll be fine testing w/ 370's. I wouldn't suggest running them long w/o a tune, but you know that.

Definitely test with starting fluid when you can. It's super easy and will somewhat isolate your problem.

As far as timing being off, you'll run into this w/ lsvtec.This is why many opt for adjustable cam gears. But your timing should be very close regardless. ( I mean within an 1/16th of an inch.)

jdm_h22

Another thing to check into... are your injectors peak & hold or saturated? Peak and hold injectors require a resistor box. They won't work without it.

DCRB

damn. looks like you were very therough before comming on here. are you still using the walbro? it might be forcing too much fuel through the stock injectors blowing out the spark...

also make sure the thermostat ground is hooked up, people miss that n then wonder why the car wont run

beecee18

^Thanx bud, heres the update from today, as soon as I showed up to the car today I wanted to overlook that jumper harness the owner was using, had a wierd feeling,
and found B2 (sheilded crank and cam sensor grounds) completely seperated at the jumper manufacturs crimp, and also D4 yellow wire for the MIL looked loose and about to pull out, so I instantly soldered and heatwrapped those together, crossed my fingers and went for it,
The start was positive and I even had instant throttle response, but after 7-10 sec it would stall and not start again, It would do the try to start thing though.
I wanted to check the fuel pressure regulator which was a used peice he purchased(didnt condone this) and split the guy apart, I knew there would be some kind of spring and diaphram and i saw a good strip of the edge seal detached and also seen the previous owner was rugged when trying to mess with it cause he caused sharp edges on the surface which basicly was right where the damage to the diaphram was.

anyways I think this is why it bleeds off so quick, and when i would try to adjust it higher to start it would suddenly drop to zero.
My hunch is that at the pressure needed the diaphram fails due to its damage.
We have an old salty OEM one that leaked right away but had a way more positive response and more pressure than i would ever get out of that used AEM. So tomorrow get our hands on another FPR, and see what happens.
All I know is in those 7-10 seconds I had 2 quick blips of the throttle and not bad startup idle, I just believe the FPR failed to even keep up with the duty the engine needs to operate. No MIL during those few seconds of glory.

One question I would have is what is the minimum pressure that the car will run at, I know I wouldnt want it due to leaning out but trying to find out if I should even blame the regulator.
Like always thanks for the input

beecee18

Absolutly all over that thermo housing everyflow chart put you right there as it seems to provide all the crucial grounds for the ECU and FI relay,
With the spark blowing out I would hope not as these injectors are from an OBD1 LS integra and service manual states 44-50psi stock so I would hope to see at least 55psi max out of these if needed.
To bad I dont have support for these hondas, only OBD2 where I would simply adjust flow rate and Latency(Dead Time) and just chuck the RC's in there but it looks like these cars require a good amount of hardware to make ECU changes
I also heard some OEM honda injectors just dont work with certain ECU's is that true?

beecee18

Yes I did check these but was scared first, used the EF manual on accident to troubleshoot the injectors, KOEO I got 12 volts out of all 4 harness clips,
and 12.2 ohms at the injectors unplugged.

well the manual wanted something like 200-300 ohms until I found out wrong manual, cracked the Integra 94-95 manual and it wanted between 12-13.0 ohms
And I think I should be getting 12 volts without the injector box, I changed all harness clips at motor with OBD1 grey clip so I dont think the clearclip would snap into the OBD1 injectors. I hate that box, And I for some reason am not a fan of RC's, When is there gonna be a denso body availible for these buggers, haha?
What do you think about the FPR guys, Does this sound like a big problem, like a cant run properly problem?
you guys are rad, and thanks for all the important input

jdm_h22

Absolutely, if the FPR is compromised your motor will NOT run like it should.

Fuel 101: A typical injector (e.i. RC's) do not read fuel pressure. All they recognize is Pulse Width, or the alloted amount of time the ecu says, "OPEN!". Soo.. depending on the amount of pressure your FPR is maintaining in the rail, the same injectors could be feeding alot or nothing.

Case and Point. Your injectors may be doing their job, your pump may be doing its job, but if the FPR is bad, your fuel system as a whole will not work properly.

spoon93

Update we tryed anOther known working fpr and still got the same results.. Is it possible this could be coming from not degreeing in the cams?

beecee18

^
NO
HAHA

I have the whole engine harness and ecu jumper out of the car and am going to go through and trace every important ground and power point, and check all cyp ckp and tdc circuits are not mixed, maybe third times a charm, update soon!

beecee18

Its only fair to the ones that helped with suggestions to this thread.

We finally figured out the problem, The Vtec solenoid was stuck open leaving it on high cam setting, that is why when it started it sounded cammed up from hell.
installed a known good working one after finding this problem via using the service port that showed oil pressure when there shouldnt have been.
And all worked well with the car starting in its lowcam state.

Then it made 212whp 143.7 torque on a dyno jet in southern california with blox b camshafts.

EFnCRX

iTrader: (1)

nice! like a bawse!

beecee18