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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
I posted this in 2 other forums that applied to the problem.
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'm getting no injector pulse (checked with Noid light). I am getting plenty of spark. MSD 6A box seems to be wired correctly.
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.
The ECM requires distributor reference pulses (DRPs) in order to fire the injectors. Whenever the ECM receives DRPs it will also enable the fuel pump relay. Since the ECM isn't enabling the fuel pump relay when cranking the engine over the ECM isn't getting DRPs.
The ECM requires distributor reference pulses (DRPs) in order to fire the injectors. Whenever the ECM receives DRPs it will also enable the fuel pump relay. Since the ECM isn't enabling the fuel pump relay when cranking the engine over the ECM isn't getting DRPs.
Fix that and the injectors will then fire.
RBob.
Should I start with the icm wiring and grounds? It's a brand new distributor, but I can still get the icm tested. Could the old PROM cause this? I got the new one coming today I believe, so I will find out. Thank you for the input!
Probably not the PROM as that doesn't affect the fuel pump relay enable.
The new distributor could have a bad ICM, not the first time.
You can trouble shoot this with the distributor removed from the engine. Plug in the connectors and using a wire lead ground the distributor body to the engine. Key-on, engine-off and spin the distributor shaft by quickly spinning the gear.
If you have the old distributor I'd do that right off and see what the outcome is. Note that if the fuel pump relay gets activated the injectors are also likely to fire. No need to flood the engine. Can pull the two injector fuses.
Probably not the PROM as that doesn't affect the fuel pump relay enable.
The new distributor could have a bad ICM, not the first time.
You can trouble shoot this with the distributor removed from the engine. Plug in the connectors and using a wire lead ground the distributor body to the engine. Key-on, engine-off and spin the distributor shaft by quickly spinning the gear.
If you have the old distributor I'd do that right off and see what the outcome is. Note that if the fuel pump relay gets activated the injectors are also likely to fire. No need to flood the engine. Can pull the two injector fuses.
RBob.
Ok. I also failed to mention that I had no voltage input at all on the injector pigtails. I think I read that there should be voltage to the pigtails with key on? Would the icm cause this also, or is this a different issue? Thank you for all the info.
Yeah fuses look good. I have another ignition module that I know worked in the old distributor. I'm going to try that and make sure I'm at TDC for timing at 0.
I found this troubleshooting method in a different thread.
"Get a noid light. Unplug a convenient injector plug in, Unplug the distributor 4P connector, turn on the key, does the noid light come on? If the Noid light is on with the key, then the fuses and wiring are intact, if NOT then you got some issues with the harness/fuses./ECM. If the noid light comes on with the key, connect a 12V test light to the battery and quickly touch the test light probe to the purple/white wire (Circuit 430) in the HARNESS side of the distributor plug. injectors should pulse and the noid light should flash as you "tickle" that wire with the 12 V test light ,you can usually HEAR the injectors click when you do this test as well. DO NOT leave the 12V attached, just quickly touch the terminal. If not, you have an open in Circuit 430, open fuses, bad grounds, bad ECM etc. If you get a reaction at the injectors and noid light from this test, then you have a bad ICM or bad connection inside the distributor. You could also have a bad TPS. If the TPS is reading WOT all the time, you will be in "clear flood" mode where the injectors will not pulse while cranking."
I tried it and nothing when I tickled the purple wire for distributor. I got 12v to each side of the pigtail. do I need to check them all? I also tried my reflashed PROM. Im wondering if I unhooked something I shouldn't have when I removed the heater stuff. I also found this fried out looking plug near the harness by the heater stuff. What is it and could it be my issue?
what is this plug for?
Last edited by 2QUIK4U; 10-09-2015 at 02:24 PM.
Reason: im dumb
Probably not the PROM as that doesn't affect the fuel pump relay enable.
The new distributor could have a bad ICM, not the first time.
You can trouble shoot this with the distributor removed from the engine. Plug in the connectors and using a wire lead ground the distributor body to the engine. Key-on, engine-off and spin the distributor shaft by quickly spinning the gear.
If you have the old distributor I'd do that right off and see what the outcome is. Note that if the fuel pump relay gets activated the injectors are also likely to fire. No need to flood the engine. Can pull the two injector fuses.
RBob.
Correct on the prom since I tried the reflashed one. I think I simulated what you explained by trying the method with the purple wire listed above. Is it time to buy a new computer? The computer box under the dash is the ECM? I hear it called ECU also
I figured out the problem lol. I plugged the computer in wrong. Both outside plugs will fit in wrong spot. Thank you for all the info and tips. Thirdgen.org has helped me so many times!
10-06-2015, 10:07 PM
