Whats up guys
havent been on here in years recently decided to get back into the honda scene as i bought my first house and finnaly have a garage. Anyway ended up trading a spare accord i had for a 96 civic coupe with a 99 jdm h22 swap.
here is the deal
The car does not start. It seems like there is too much fuel beeing dumped on start up.
in order to start the car u have to unplug the resistor box which of course couses the injectors not to have power than once the car wants to start u have to have another person plug it bak in in order to supply fuel than the car runs rough but after a minute it idles ok
than u can drive the car but it runs rich.
once the car is warm it wil start no problem and idle fine(which i do Not understand)
-was told the car had at one point bigger injectors in it which im assuming were low impedence as dude had a resistor box installed. When i got it it had high impedence oem injectors installed wasnt sure what size so i went ahead and installed 99 prelude 290cc injectors that belong to that motor. They were flow tested cleaned etc.
- eliminated the resistor box by connecting the 4 injector wires to 5th wire which i believe is the power supply to them. From my understanding i do not need the resistor box with high impedence injectors...
- the ecu is a chipped p28 with some type of a tune assuming for larger injectors so i have ordered a chip with a stock h22 map on it for the 290cc injectors
- replaced spark plugs/and wires
-im stuck at this point not sure what else to do.
car has everything it needs to start normaly and run as should.
-has spark def. has fuel.
crazy part is i drove the car about 70 miles home perfectly fine (but rich)and started it about 5 times before making the trade. Car was warm when i first looked at it therefore it started fine all those times. (Mistake number1)

- from here i thought about geting a p5m ecu but than there would b all sorts of check engine lights etc... not sure what to do next. Any suggestions any one?

Still waiting on the new chip with the 99 h22 tune/map
Qustion-if i take the chip out of my p28 does that return the ecu to its stock form?
-Also if obd 2 h22 injectors r 290cc
than how is everyone using obd 1 ecus on all the h22motors if obd 1 h22 had low impedence 345cc injectors?

Thanks for the reply
yes im aware that the “tune” i ordered is not something that is specifically for my motor and more so a basemap in order to get the car to the dyno but in my siatuation im looking to get the car started first. At this moment i have a p28 with a basemap for a 92-96 obd1 h22 and a actual 99 motor with saturated 290cc injectors no resistor box and car will not start with having the same issue described above(too much fuel) at this point the new “chip,tune,basemap” that im waitin for is just a waste of time accoring to what you are saying? And peek nd hold 345cc and saturated 290cc injectors flow identical you are saying since i can use either set?
Motor is in its stock form, with that said what is my best choice for ecu with out mentioning any chips or base-maps or dyno tunes in ur oppinion? P13?

So new chip is in and still only way to start it is to limit the fuel at start up. Thought it was dumpingtoo much fuel but now since new tune is in along with correct injectors im starting to think fuel amount is fine but its just not burning it like the spark is weak.
Only way to start the car is to crank it without the injectors beein connected via where the resistor box used to be than connect that so there is power to injectors as i crank it. than keep it at around 2k rpm for about a minute than the car runs great. Seems like its not slugish anymore and its feels even better with the newer map. I tested the engine coolant temp sensor
getting 5v to it the continuity is good sensor has resistance that changes according to temp exactly as the new one does which i purchased just to compare.
Like i said currently leaning towards weak spark theory almost like when motor is dead cold something in the distributor is not functioning properly. Seems like many h22 motors wether swapped or not have this cold start issue where they dont start or start and run like complete s**t! Im getting pretty frustrated at this point.
-wanted to add that once the car is idling fie i drive it than i can start the car 10 times im a row nd starts perfect everytime. Also can let it sit about 30-45 min depending on the temp and restart it no problem. Than once dead cold back to same issue. It doesnt make sense

it has a stock fpr and checked for any leaks in that region everything looks fine
as far as it running warmed up no more black smoke it runs great feels more responsive and just feels good. I will double check the mentioned areas. Thanks

i bought a replacement ect sensor and measued both of them
they both change resistance according to temp identically. Did not reach operating temp with the way i tested the old one but im worried about the cold temp here as it would alter the fuel mixture if it was not functioning from what i read.
as for the iat sensor i did not test or even think or that i will check the power continuity and resistance to that later on i will report back thanks for all the help and pointers this is driving me nuts 🥜
greatly appreciated!

Well gentleman... it got a little warmer in jersey (20 degrees F to about 50->51 to be exact as of 48 minutes ago) and i decided to give it another whirl in the garage. Mounted 4 2000 em1 si wheels with brandy new tires on my rig. After i completed the task something told me to give it a shot at cranking this hot rod and gues what. Sucker started right up. Ren rough as it would with my other method but help of a friend was not needed. No cutting out the power to injectors and plugging them back in as im cranking the motor needed. Pretty wild. All i jad to do is keep it at roughly 1800rpm and about 45 sec later boom runs phenomenal. Im so lost at this point...
something strictly temp related?...??!?!!? I gues h22 is a summer motor? Makes no sense