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No pulse to fire the injectors?

Posted: Sun Apr 10, 2011 2:59 pm
by BillB
Ok so some back ground. The cars a EF7 CRX which is a JDM model with a DOHC ZC in OEM form. Mine has a B18c swap using a odb0-odb1 harness using a P30 ECU which will run with my copy of eCtune once it starts....... The harness was a boomslang which didn't work so I made changes using THIS which has worked on many EDM/JDM cars before. After searching around the web I found a few things to check out... The three sensors in the Dizzy TDC/CYL/CRANK & they all test out with the right resistance to be working at the ECU plugs so the wiring/dizzy look to be fine. PGMFI ground issues is a well known cause of weird problems so st's ultra clean & has a separate feed direct from the negative terminal of the battery! There's also grounds from the battery to the chassis leg on clean bare metal to be sure as well as to the gearbox & valve cover. I'm running ITR OEM 240cc injectors for now to get the car running (I have ID1000's for when the turbo goes on after the engines ran in) so I've changed the injector plugs over to the ODB2 plugs & deleted the resistor box. I've checked that the 12v feed is provided by the main relay & that the four injectors are wired back the the right pin on the ECU. After all this I don't get any pulses from the ECU to fire the injectors. If I squirt a bit of fuel past the throttle body the car fires so spark etc is here I also checked the spark & it's strong enough. One weird thing I noticed is if I unplug the EACV the main relay shuts off I think & when you plug it back in the fuel system re primes? So I thought there must be an earth issue as it seems the EACV earth is earthing more than just the sensor! Please help I'm so tired I can't think anymore but I really need the car running now asap! As it looks like I might be loosing my job I need to have this running so I can sell my daily driver to pay my bills maybe :cry: Bill

Posted: Fri Feb 03, 2012 6:43 am
by barry
Have you fixed this issue? Check to see if your FI e/m fuse isn't blown that controls injectors ....you may not have one tho ....but look

Posted: Fri Feb 03, 2012 12:26 pm
by elevation
check the ground on the thermostat housing.

Posted: Fri Feb 03, 2012 4:48 pm
by joppez
Check distributor wiring, i had kind a same problem converting my obd0 dohc non vtec to d16z6, i was using some internet guide to wire distributor and tdc/cyp or something was mixed and got no fuel but car runned with carb cleaner :roll:

Posted: Fri Feb 03, 2012 4:50 pm
by joppez
The three sensors in the Dizzy TDC/CYL/CRANK & they all test out with the right resistance to be working at the ECU plugs so the wiring/dizzy look to be fine.
I did exact same thing, but resistance is about same so you dont know if wiring is right, only that there is something :D

Posted: Fri Feb 03, 2012 8:37 pm
by JaredKaragen
joppez wrote:
The three sensors in the Dizzy TDC/CYL/CRANK & they all test out with the right resistance to be working at the ECU plugs so the wiring/dizzy look to be fine.
I did exact same thing, but resistance is about same so you dont know if wiring is right, only that there is something :D
Correct. You can ohm the pickup, but the signal is the important part and the only way to check it is with an oscilloscope (lab scope)