No injector pulse. 1991 L98 TPI
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Car: 1991 Z28
Engine: 5.7 TPI L98
Transmission: 700-R4
Axle/Gears: Moser 9" with 4.11
No injector pulse. 1991 L98 TPI
I'm getting no injector pulse (checked with Noid light). I am getting plenty of spark. MSD 6A box seems to be wired correctly.
I installed a brand new distributor and set the timing on crank to 0. I tried the firing order 180 the other way in case I wasn't TDC.
New FPR and im trying to set it (unhooked, and hooked up to vacuum lines). I can hear the fuel pump when I turn key to the on position and it hits 40 and drops off slowly. Fuel pump does not come on any more as I turn it over.
I installed new AFR aluminum heads and pretty sure I regrounded the straps and wires attached to the old heads to the block.
I also deleted all the smog equipment..EGR, vapor canister, vacuum lines, plugged all vacuum leaks, etc. I put a breather on the gas tank vent.
Deleted the cruise control and vacuum ball. Deleted the AC, and the heater fan (for now) unplugged a lot of connectors to the heater stuff.
Electric fans are wired to a manual switch. Stock wires are unplugged.
*Sensor that is on the passenger side head is unhooked. I plugged the head when I couldn't find the sensor. I thought it was for the fans to turn on so I didn't buy a new one.
*I am using the stock chip. This chip was sitting in a plastic bag for 15 years. I sent the PROM I was using the past 15 years back to TPiS for a new tune reflash for the heads and intake port work I did.
Im not getting a security code
My questions for no injector pulse:
Do I have something unplugged or deleted that is causing this?
Is it the stock PROM?
My timing too far off cause no injector pulse?
Does low fuel pressure cause no injector pulse?
I installed a brand new distributor and set the timing on crank to 0. I tried the firing order 180 the other way in case I wasn't TDC.
New FPR and im trying to set it (unhooked, and hooked up to vacuum lines). I can hear the fuel pump when I turn key to the on position and it hits 40 and drops off slowly. Fuel pump does not come on any more as I turn it over.
I installed new AFR aluminum heads and pretty sure I regrounded the straps and wires attached to the old heads to the block.
I also deleted all the smog equipment..EGR, vapor canister, vacuum lines, plugged all vacuum leaks, etc. I put a breather on the gas tank vent.
Deleted the cruise control and vacuum ball. Deleted the AC, and the heater fan (for now) unplugged a lot of connectors to the heater stuff.
Electric fans are wired to a manual switch. Stock wires are unplugged.
*Sensor that is on the passenger side head is unhooked. I plugged the head when I couldn't find the sensor. I thought it was for the fans to turn on so I didn't buy a new one.
*I am using the stock chip. This chip was sitting in a plastic bag for 15 years. I sent the PROM I was using the past 15 years back to TPiS for a new tune reflash for the heads and intake port work I did.
Im not getting a security code
My questions for no injector pulse:
Do I have something unplugged or deleted that is causing this?
Is it the stock PROM?
My timing too far off cause no injector pulse?
Does low fuel pressure cause no injector pulse?
#2
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Re: No injector pulse. 1991 L98 TPI
Have you tried manually pulsing the injectors and then cranking it to see if it fires? This would help verify the lack of pulse. Probe the injector pigtails to make sure you have 12v on each bank. Fuses good? The ICM is supposed to send a signal when cranking and running to the ECM that then pulses/grounds each bank. Make sure the pins inside the ICM connector did not get bent when plugging the wires into the distributor...use a phone to take a picture back there so you can see that the pins are straight. NOIDs are hard to observe; I turned light out in garage while using this tool just to make sure.
Going to be sweet when it fires!! Did a really nice job under the hood, looks sweet.
Going to be sweet when it fires!! Did a really nice job under the hood, looks sweet.
Last edited by MrPackstin; 10-06-2015 at 10:54 PM.
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Car: 1991 Z28
Engine: 5.7 TPI L98
Transmission: 700-R4
Axle/Gears: Moser 9" with 4.11
Re: No injector pulse. 1991 L98 TPI
Thanks! I will try all those tips and I should have the reflashed PROM later this week. Hopefully one of these variables does the trick. I want to drive this thing before it snows!
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Car: 1991 Z28
Engine: 5.7 TPI L98
Transmission: 700-R4
Axle/Gears: Moser 9" with 4.11
Re: No injector pulse. 1991 L98 TPI
I also read some posts about making sure the distributor or ICM is well grounded?
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