Civicsoulja21

Okay guys, this is my dads old build he gave up on so here it is...

Motor is a b18a1 bottom ended bored to 81.5mm
eagle rods
cp pistons (11.3:1 compression with head and all)
arp head studs and rod bolts
kings bearings
b18c (jdm gsr head)
ctr exhaust cam and gsr intake cam
supertech valves, springs, and retainers
skunk2 cam gears
ported head
Jackson racing supercharger @ 6psi
dsm 450cc injectors
dc header and exhaust
blox test pipe
comp stage 2 clutch and lightened flywheel
255 fuel pump
blox fpr
type r distrinuter
p28ecu tuned


Soooo my problem is that i think all the jumpers and harnesses are in check all sensors i was said to have are there other then vtec oil pressure switch, which im just waiting on a new solenoid thats pre tapped. but everything should be in check it. motor and supercharger oil and such have maybe 400 miles on them. im getting fuel, i have good compression, no knocks, but i get no spark. maybe pins in the harness for the dizzy are mismatched or something. i had a d16y8 stock ex harness in until my tuner said to put in a 2000 si harness and once i did i got no spark as a result. what do you guys think my problem might be?? i can also answer any questions you guys have to help my search for an answer.

grumblemarc

iTrader: (4)

So put the original harness back in.

turbohatch96y7

iTrader: (15)

No spark is simple to diagnose.
Check for 12v at the distributor coil.
Most likely you don't have voltage then trace back to your Key switch. That simple no relay's in between.

Civicsoulja21

I plan on checking for power all the way through(dizzy, battery, plug wire an I have new 4554's to put it). I check the dizzy harness and it seems one of the plugs in the engine harness itself might have a missing plug I am not too sure I got some pics though. Compared to all the other ports this one almost seems to have little to no metal to touch the plug. I will post pictures tonight of the dizzy plugs and see what you guys think. It ran with the y8 harness but the harness was hacked to ****, the car also ran very shitty no like breaking up if I'm correct ,but I think was the map sensor, the car shut of under WOT once you got into third

Civicsoulja21

Does anyone have any suggestions? pics up tonight or tomorrow night

wantboost

iTrader: (2)

The ex and si harness are identical except for one being obd2a and obd2b (si) each uses different ecu plugs so keep the y8 harness. I'm using my y8 harness on my lsvtec without issue.

Civicsoulja21

heres the link to photobucket

http://s1189.photobucket.com/user/brizzleb21/slideshow/

Civicsoulja21

the guy who put the si harness in said the y8 one was hacked and was better to do an si harness and once installed the car would no longer start and it also has the correct jumper harness or at least I thought. the car was setup for a jdm gsr with the y8 harness and went from obd2b jumped to obd2a for the p72 ecu but the my father jumper from 2a to obd1 with the y8 harness and now its si harness from obd2b to obd1. im honestly not good at all with wiring so that's why I come to ht

wantboost

iTrader: (2)

There isn't a difference between the two other than ecu plugs. I have the harness out of my si and my y8.. no difference.

Katman

While you're correct about the OBD2a/b ecu connector plug differences, it is false to say they are 'identical'. For the record, he mentioned he had an 00 EX harness, not a 96-98 EX harness.

1) Si harnesses have a "big dizzy plug" which plug n play to OBD2 DOHC distributors, while 99-00 civic EX (and lower grade models) harnesses sport the 'small dizzy plug' that need to be converted to a 'big dizzy plug'.


2) All of the OBD2a/b civic harnesses (non Si) have a 3-wire CFK sensor plug while the Si harness has a 2-wire CKF (b-series) sensor.


CivicSoulja,

what ecu were you using when you had the Y8 harness in there?
and what has been done to the OBD1 ecu? is it stock or chipped or have Hondata?
Has your fuel injector sizing changed? or are you still using the same injectors you had before swapping to the Si harness?

Things that come to mind why your car wont start...
- changed injector size (larger CC) and your OBD1 ecu isn't reprogrammed to these injector size specs
- questionable/faulty OBD2b to OBD1 jumper harness adapter
- Si harness isn't an Si harness - you did mention an ECU plug looks like its missing, correct?
- all ground wires properly fastened?
- Do the terminator plugs or sometimes called 'dead end plugs' on the Si harness have their terminator plugs fully pressed in? if any of the terminator plugs are slightly unfastened this could make the car not run/start up. Here's these plugs look like:
https://honda-tech.com/attachment.ph...1&d=1248737338
located on the underiside of where the intake manifold goes and then over by the clutch master cylinder/driver side firewall area.

wantboost

iTrader: (2)

My ex harness has the same connector as my obd2 b16 distributor. Obd2 vtec distributors should have the same plug as all obd2 vtec harnesses.

I didn't know about the ckf difference. I have both harnesses but since I'm building a 97 ex I'd prefer to keep the ex harness. I'll have to swap the ckf wiring/plug over from my si harness.

Katman

Not sure what year your EX is, but that means you have a 96-98 (OBD2a) EX harness; or if you have a 99-00 (OBD2b) EX harness, then it has been modified either by you or someone else prior to your cars ownership or thereof.

Again, only 96-98 civics, 96-01 integras, and 99-00 civic si's have the big plug dizzy from the factory.
Honda changed 99-00 civics (excluding Si) to a 'small dizzy plug' (as linked above) for some dumb reason; this is includes the EX which is a vtec model.

wantboost

iTrader: (2)

I have a 96-98 ex harness and a 99-00 si harness out of my old em1

Katman

ah yes, well that explains why you have the "big dizzy plug" on both of your harnesses and why the OP's EX harness does not.

Civicsoulja21

originally a p72 for the gsr but once we had the motor assembled we put in dsm 450cc injectors and then had it tuned with the phearable p28 ecu. ive used both ecus with the y8 harness but ever since I got the car back from the shop it ran like ****. im trying another dizzy and ill post a pic of my ecu plugs in day light and ill check for terminator plugs

Katman

im wondering if the P28 ecu is faulty as well.
are you getting any CEL lights with the P28 ecu at all? if so, what CEL codes are you getting?

was the P72 GSR ecu OBD2b? if so, did you have the immobilizer removed or replaced with a bypass chip and also perform the fuel pump relay wiring mod on the Y8 and Si harness? OBD2b integra ecu's use a different ecu pin out for the fuel pump relay vs. a 99-00 civic.

wantboost

iTrader: (2)

I find it hard to believe both harnesses and ecus are having problems

Put the y8 harness back in, toss the stock injectors and the y8 ecu and see if it runs (a y8 ecu will run a dohc motor no problem)

I don't know why you've tried different harnesses, jumpers, ecus etc

You know it runs on the y8 harness, so take the time to clean that harness up, reloom it and save yourself the headache. It's always a bitch when it comes to wiring but why have 2x the headache with harnesses and add to that multiple ecus.

Fix the y8 harness, find a working ecu (I prefer a p72 because I like having a knock sensor) and sell the other **** to focus on other areas of the car. Or use it to buy beer and put a stripper through college

Civicsoulja21

I will have to try to see if I get a cel I cant plug a reader in due to obd2-obd1 swap, but with key on it doesn't throw any codes. it was a 94 jdm gsr so obd2a ecu. ran great till the build...I wonder if its the terminator plugs or ecu plugs because it would at least start with the y8 harness but once WOT through to third it would shut off. so it always had problems since built...I get everything but spark, im going to bolt up a friends dizzy to see if that helps but I doubt it. and I cant use a stock ecu anymore, stock ecus will not allow the car to start once supercharged otherwise I have the p72 and the jumper harnesses to run it p72 again.

I can also try cleaning the grounds, I have 3 or 4 (tranny, battery, core support, and I believe one to the charger but not 100% sure) to see if those help get spark. I do have fuel, compression, and air going in though.

turbohatch96y7

iTrader: (15)

Did you check for spark? Did you verify 12v at the distributor coil?

turbohatch96y7

iTrader: (15)

Spark
timing
air
fuel
compression
Find what's missing. Also make sure your battery is fully charged when cranking the motor over.

wantboost

iTrader: (2)

Obd1 ecus have an led that flashes the code. Its inside the ecu

A stock ecu will crank anything with stock injectors. Regardless if it's turbo or supercharged. We aren't talking about driving around and beating on the car, simply seeing if it will crank and idle for diagnostic purposes

Civicsoulja21

I have checked spark, nothing but i am trying a whole new dizzy in 2 days so the coil should be all better if that's it. I just put a new battery in but it was from a friends part out car that ran fine and started fine so I don't think its that but Ill pull my dads battery for a test run or ill try to jump it.

and ill check the ecu as well to see if it is flashing anything too!

Katman

That is incorrect about OBD1 ecu's. They do NOT have an LED inside.
Only pre-OBD1 ecu's have an inner diagnostic LED ie. OBD-0 (86-87 civic/crx Si, 88-91 civic/crx, 86-91 integra)

For OBD1/2 vehicles & ecu's, you jump the 2-pin diagnostic plug (a paperclip works) that's found to the right side of the glove box to allow a solid CEL light to blink MIL codes.

btw if you have no spark, perhaps your ignitor or coil has gone bad (inside the dizzy). If you have a spare SOHC dizzy of the same OBD type, you can swap out each one to troubleshoot if that could be your problem. But if the dizzy was working fine before the engine harness swap and/or before converting to OBD1, then it sounds like either the Si engine harness is suspect or the OBD2-OBD1 jumper is. Did the OBD1 conversion harness and P28 ecu work fine with the Y8 harness?

Also, something else that comes to mind is if your Si harness isn't truly an Si harness, it could possibly be an engine harness from an AUTO EK civic. Auto EK civic harnesses in their stock form used on a 5spd engine or w/5spd ECU or in a 5spd chassis (or a combo of the 3) will not allow the engine to start.....I have yet to personally find out why this is the case with the auto EK harnesses.

If you want to double check that you have an OBD2b engine harness, check out my diagram below.
Your engine harness that leads to the ecu should have 3 total plugs as seen in the "OBD2b" photo below.

wantboost

iTrader: (2)

Sorry I've been playing with nissans, z06s and professional drifting cars a bit too long. My honda kung fu is a bit rusty lol

wantboost

iTrader: (2)

Aa far as the auto harness goes (I've been reading pinouts non stop) there are some things that change as far as pins at the ecu are concerned, things that need to be changed or the car won't start