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tpi injectors wont pulse
the tpi set up came out of a 1991 trans am
new stand alone harness and a chip from pcmforless to delete the VATS the motor is out of a 1988 chev 3500 2wd i swapped a set of S/R heads on it
You maybe able to get pulse without the memcal. If that's the case it's a vats issue.
If you have power to the injectors it could be a ground issue ecm d6 & d7. or a signal issue with the purple and white stripe wire coming from the ICM going to the ECM . Or even a bad icm can still have spark without injector pulse.
Last edited by Tuned Performance; 03-29-2017 at 03:59 PM.
Reason: Ecm pins
You maybe able to get pulse without the memcal. If that's the case it's a vats issue.
If you have power to the injectors it could be a ground issue ecm d6 & d7. or a signal issue with the purple and white stripe wire coming from the ICM going to the ECM . Or even a bad icm can still have spark without injector pulse.
I did try a different ecm thinking it could be the problem how do I test for a bad ground on d6 & d7 or signal.
You can check the grounds and signal for continuity. Do you have a mil to indicate if the ecm is powered up ?
mil meaning malfunctioning indicator light ?
I do have a check engine light that lights up when I power it up. I also have a obdI code reader when I hook it up says no codes
Is your RPM gauge bouncing during cranking? If it is totally still then your pickup coil is not sending a signal.
its just sitting on the floor at the moment with a stand alone wiring harness so i dont know but i did replace the dist with one out of a working car to see if that was the problem.
i know from trying this set up before i had spark and when it was in my camaro i had good fuel pressure it was the injectors not pulsing and i gave up and went back to carb on my camaro. This set up i want to put in my 84 k30.
I didn't watch the video earlier. What was the fuel pressure in the other vehicle, and what is it sitting on the ground?
VATs kills injector pulse
Bad pickup coil can cause no pulse
Bad ECM can cause no pulse
grounds can cause no pulse
I think that is about it. I couldn't hear in the video, but what sensors are not plugged in currently?
On my Camaro I had 45psi and at the moment there is no fuel going to the motor while it's sitting on the ground. I am just looking for the injector pulse then I am going to install the motor in the truck and hook up the fuel system.
The stand alone harness I have only has one ground loop and I have that on the back of the head. The sensors I don't have hooked up are the O2 air temperature and the fuel injectors but using a noid light to look for injector pulse.
I have tried two different computers and two different distributors.
I also had pcmforless burn me a chip to delete the vats and at the moment that's all I can think is wrong at the moment
If the pcm for less chip is on a piggyback adapter with the chip removed and memcal in place you should have injector pulse running off just the netress( limp home mode) .
If the pcm for less chip is on a piggyback adapter with the chip removed and memcal in place you should have injector pulse running off just the netress( limp home mode) .
wouldn't the VATS not allow the injectors to pulse
The chip would have to be removed from the piggyback holder with the memcal hooked to the adapter. D8 should be checked for continuity from the icm plug to the ecm. The notch on the chip will be towards the outside edge when returned to its original position. http://tpiparts.net/1227730_pinout_diagram
What are the ohm readings on your injectors? Have you changed the injectors out during any of the TPI swaps?
Any open injectors or any out of the 12-16ohm readings unplug and see if you have pulse then.
Saw your other post, so all of your injectors are unplugged currently?
Also check what you TPS voltage is reading, anything over 4V during cranking will put the computer in clear flood mode.
I dont reremeber if i did switch injectors years ago when i first tried getting this set up to run. If i did it would have been more likely from a LT1 do to me having a couple of those motors over the last 10 or so years.
I did ohm them out and it was 12.4 and 12.8 and i do have them all unpluged
I dont reremeber if i did switch injectors years ago when i first tried getting this set up to run. If i did it would have been more likely from a LT1 do to me having a couple of those motors over the last 10 or so years.
I did ohm them out and it was 12.4 and 12.8 and i do have them all unpluged
The TPS 4.42 closed 0.735 WOT
The tps readings are bass ackwards , blue wire to blk wire grey is 5v ref.
From top to bottom blk, blue, grey.
The injector impedance seems low, iirc they should be 15.5-17 or so.
The icm connector looks right the letters are on the other side of the body of the connector. http://www.iroczone.com/2009/10/adju...on-sensor-tps/
Last edited by Tuned Performance; 04-02-2017 at 08:27 PM.
Throttle closed WOT This is from one of my stock pile of lt1 parts A 40# one I have sitting on my shelf I am thinking the injectors I have on the motor is from an LT1
i was getting my readings earlier from the wrong wires
Sounds like you have covered it all for injector pulse. It must be a vats issue. Maybe ecm for less can just send you a new eeprom to replace yours. I would of thought with the eeprom bypassed you would of had a code 41 or 51 but still have injector pulse bypassing vats. Got me stumped what the issue might be.
Sounds like you have covered it all for injector pulse. It must be a vats issue. Maybe ecm for less can just send you a new eeprom to replace yours. I would of thought with the eeprom bypassed you would of had a code 41 or 51 but still have injector pulse bypassing vats. Got me stumped what the issue might be.
I think I'm out too haha. At this point it has to be either VATs or a bad ground or wire.
In post #6 Tuned Performance said to check for continuity from d6 &d7 to the ground on the back of the head. Did you do that?
Did you check all the ecm power wires. The ecm can appear as it's on with the check engine light illuminated but without the switched ignition feed (a6) you will not have injector pulse.
I was playing around with my scan tool today and found a spot where I can see what the computer sees and when I was cranking over the computer isn't picking up RPMs. Would that be the ignition control module on the distributor?
I was playing around with my scan tool today and found a spot where I can see what the computer sees and when I was cranking over the computer isn't picking up RPMs. Would that be the ignition control module on the distributor?
Since you have spark, the more likely culprit is the ignition pickup coil.
You can test it with your ohm meter should be between 500-1500 ohms
Last edited by mcgarnicle; 04-19-2017 at 03:00 PM.
03-29-2017, 01:38 PM
