Join Date: Aug 2012
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No Injector Pulse...Help Please!
Disclaimer: To start off, I've been a member since 2007 but haven't signed on in years. I couldn't remember the credentials to my original account so I opted to make a new. I don't intend to be seen as somebody making an account to get some quick advice. Now that I own an Integra again (2 actually) I intend to start contributing again as I did in years past.
In addition, trust me when I say that I have used the search feature. I spend days and days researching on various forums and ProDemand before I even think about creating a post.
OK haha...here we go...
Shell: 1994 OBDI GSR Shell
Engine: 1996 OBDII B18B1 w/ Main Harness
ECU: OBDI P75 socketed by Mad Fab Lab
Injectors: RC PL9 550's with Resistor Box wired in
Distributor: New OBDII Dizzy from Advance Auto Parts
Synopsis: 12+ volts to each injector clip but no pulse with noid light.
I have an OBDII (1996) B18B1 swap into OBDI (1994) GSR shell.
The motor was running when I pulled it a few years ago. Before putting it in the new shell, I made sure it wasn't seized. Prior to dropping it in, it got a new thermostat, timing belt, and water pump.
I am using all OBDII sensors and OBDII engine main harness.
The OBDII main engine harness is plugged into the OBDI subharness at the strut tower.
The OBDI subharness is plugged directly into an OBDI P75 ecu that I bought around 4 years ago that I have never used**
After placing the engine in the bay, I installed all of my turbo components and added fluids.
I then pulled the plug wires and injector clips to prime oil through the feed line.
Plugged the plug wires and injectors back in and turned the key on. Walbro fuel pump primed perfectly.
I decided to try to crank it and got a no-start condition. After checking over everything and verifying all electrical connections were good, I checked for spark.
Moving forward, I put a noid light on the injector clip to test for injector pulse.
I then noticed the distributor was quite loose and I don't know what prompted me to pull it off to inspect it as opposed to just tighten it down, but I'm glad I did. The teeth on the key where it mates into the slots on the cam had broken off.
Luckily, the teeth hadn't fallen down into the head so I was able to pull them out without removing the valve cover.
I replaced the distributor with a brand new assembly from Advance Auto Parts and I was positive that this would cure both issues.
Now I have spark, but still no injector pulse according to the noid light. I did read on another forum that a noid light won't illuminate with a resistor box wired in but I'm not sure I trust that logic. Also, if I send ground to the injector from the ECU plug, the noid light illuminates.
All of my injector clips have 12+ volts on one side but they are not getting signal from the ECU to pulse ground. Each injector ground wire from the clip to the ECU ohms out at 0.4 ohms.
If I understand correctly, the ECU gets the input from the sensors housed within the dizzy to pulse the injectors.
I was worried about pins being out of place by plugging the OBDII main harness straight into the OBDI subharness and directly to the ECU but I ohmed out the wires from the ECU to the distributor plug by cross-referencing the OBDII wiring diagram with the OBDI diagram. So the distributor in fact does have continuity with all the proper ECU pins.
I've also checked the ECU plug for 12+ volts at IGP1 and IGP2, which it has. I did this check with the ECU unplugged but I don't think it matters for that test.
I'm about to go double check the grounds for the ECU.
I don't want to jump to the conclusion of a bad ECU but I'm starting to lean that way a little more as time goes on.
I'm sure there is just something that I missed.
I wanted to see if you guys have any input on something simple that I may have overlooked, did improperly, or any advice on how to test the signals coming from the distributor for the CKP, CYP, and TDC sensors.
Any input is appreciated!
Looking through ProDemand again, I found the testing procedures for the Crank Position Sensor (CKP) for the OBDII distributor.
It says to ohm out pins #2 and #6 on the distributor plug and look for resistance between 500 to 1000 ohms.
I got a reading of 450 ohms.
With it being a little lower than the parameters, I figured I'd test the broken distributor I pulled off to see what it read. I actually got lower on that one...about 417 ohms.
So now I'm left wondering if around 450 ohms is acceptable or if just coincidentally both CKP sensors are bad. Is it possible that I just happened to get a faulty new distributor from Advance Auto?
I just had a local guy come by with his CRX and we swapped my OBD1 ECU into his car and it fired right up, so my ECU is good.
Last edited by iamshane123; 07-15-2016 at 12:59 PM.