New to 5.3ls... need help getting it started
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Teching In
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New to 5.3ls... need help getting it started First of all, let me say what a great site. I am putting a 5.3ls into my 88 grand wagoneer. The conversion is 95% complete and it has been as awesome project. I finally got to the point where I could try to start the engine but I quickly discovered that I do not have any spark. My first stop was the crank position sensor and it read the reluctor variance just fine (10 vdc then 0 vdc and so on). I moved on the perform the same test on the cam sensor and did not see any variance, just a constant 10 vdc. I put a new sensor but got the same results. The system is not throwing any codes. Any thoughts?
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Well I have verified that the harness did come with three grounds, and they are all connected to the back side of the heads. I have gone to every plug on the harness and applied dielectric grease to connectors. Did the same with the grounds. The engine is grounded to the frame, the body and directly to the batt. I know that is over-kill, but I am absolutely running out of ideas.
The ground for the coils is usually up front of the engine on the left side and wont reach the rear of the heads, so are you absolutely positive its hooked up? Maybe an aftermarket harness they move the grounds, but I wouldn't think a converted factory one they would?
Last edited by ls1nova71; Sep 5, 2014 at 04:14 AM.
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I'm guessing you have, but have you pulled a plug, left it attached to the plug wire and watched to see if it is sparking? I know there are less redneck ways to check, but if my spark checker doesn't light up I'm pulling the plug to do this anyway...
I feel your pain though, chasing this kind of stuff at the very end really sucks.
I feel your pain though, chasing this kind of stuff at the very end really sucks.
Thread Starter
Teching In
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I am absolutely certain that all of the connections that I was given have been plugged in... not so sure if the crank and/or cam sensor are in the correct pin out on the computer. I verified that the crank sensor is operating correctly, but when I performed the same check on the cam sensor I did not get the voltage variance at the engine was turned. I changed the sensor but got the same results. What could that mean?
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1 better I think. I had the folks at Novak Conversions reprogram the ECM originally. When I was unable to get it started, I shipped the ECM back to Novak, they plugged the computer into a bare engine and tranny that they use for testing and it started right up. Definitely no VATS on this one. Thanks for the input.
12 Second Club
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From: 217
Have you charged your battery? I think minimum voltage to run is between 8-10vdc. But at low voltage the coils may not be able to build up required voltage to fire. You should have 12vdc at coils. Try bringing your battery all the way up and retest.
Andrew
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From: 217
that's the what the OP said he had, but didn't mention If the battery was fully charged. Once the voltage gets to about 10 volts the engine will start to misfire and die. I'm sure you have started and ran one without the alternator on before and had that happen.
Thread Starter
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The battery that I am using is fully charged and maintains voltage when cranking. I am hoping that all of this can be resolved without sending the harness back as it is already loomed and mounted. Not against the idea completely, just hesitant.
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From: 217
Since you have a good crank sensor and a known good PCM.
1)verify harness is pinned correctly
2) Check continuity between crank sensor plug and PCM connector terminals.
3) check continuity between pcm and coil connectors terminals
4)check harness from coil connector terminals to each individual coil terminals.
5)If harness fails find issue and repair or send back
6) If harness passes, verify input from crank sensor to PCM and PCM coil output to coils.
We are assuming all pink wires are keyed hot in crank and run.
1)verify harness is pinned correctly
2) Check continuity between crank sensor plug and PCM connector terminals.
3) check continuity between pcm and coil connectors terminals
4)check harness from coil connector terminals to each individual coil terminals.
5)If harness fails find issue and repair or send back
6) If harness passes, verify input from crank sensor to PCM and PCM coil output to coils.
We are assuming all pink wires are keyed hot in crank and run.