24x Swap no Spark
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24x Swap no Spark So I ended up licensing my bros 02 caddillac 6.0 tune..I removed vats and still does even fire or try to start. I pinned the cam and crank sensors according to the 99-02 schematics for LS1 f Body. Maybe the Cadillac pins em different?. Im using the same cam and crank sensors that were used on 96 02 L31s. Crank sensor is part number 12562910.
Would it start even if the distributor is not in right? The 4x setup I was running would start even if it was off and then I would set it using the cam offset pid.. I segment swapped engine and engine diagnostics.
Can some one help me out, total noob here. Pulling my hair out. Thought it was a ground issue but same thing no spark. Not sure if I flashed the correct tune either, got a little exited, could someone take a look an see if my issue is the tune or mechanical ?
Would it start even if the distributor is not in right? The 4x setup I was running would start even if it was off and then I would set it using the cam offset pid.. I segment swapped engine and engine diagnostics.
Can some one help me out, total noob here. Pulling my hair out. Thought it was a ground issue but same thing no spark. Not sure if I flashed the correct tune either, got a little exited, could someone take a look an see if my issue is the tune or mechanical ?
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Hey bro whats up thanks for replying , Yeah I was running a single coil and dizzy with the 0411 and everything was good, Have wanted to do the 24x swap for a while now and here I am, Yeah I am still using dizzy as cam sensor. Well so far everything looks correct. Have 12v and ground were it needs to be but I cant even get it to sputter. Hp tuners VCM shows rpm readout, inj pulse, I can smell fuel so injectors are firing, but no spark.. I made my own harness so maybe I messed up somewhere. Not sure if my tune correct either . Total noob bro but I'm trying.
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My crank and cam sensor read 11.5v on the 12v reference wire , I hooked a test light to them and it was real dim, Test light, lights up nice and bright with 12v, They are suppose to have 12v correct ? I Also pulled crank sensor and tested it by waving a metal thing in front of it, injectors click and pump primes every click but no spark.
Just wild guess but maybe providing some more information as to the exact setup would help us to even begin making suggestions. What car are you working on, what is the motor setup, what conversion was done. It seems like your doing a 411 conversion on a non LS motor since your using a distributor? If that's the case, have your verified proper timing, have you verified actual spark?
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My engine is an L31 sbc with an Lt4 hotcam and a Ramjet 350 tuned port Intake manifold. So I started with an 02 Express van 0411 ecm and harness which I tore down and cut a lot of stuff out. Got it tuned in SD and was running the 4x reluctor crank sensor signal with the distributor and was running great for like a year and now here I am trying to "ls swap". Got the 24x reluctor in there and got a Holley aluminum timing cover. I am using a cam and crank sensor off the 02 Express van.. I tried using the Xvan tune by switching the crank lo res settings to 0 but no luck. So I read that I need a LS1 tune or a 6.0 tune with same os. So I opted for my bros 02 Cadillac escalade 6.0 Licensed the file and flashed it but no luck. Segment swapped my engine and diagnostics sections but no luck with the spark.
Last edited by Wesos624; Dec 2, 2022 at 11:42 AM.
"trying to ls swap" meaning converting the current motor to a coil on plug setup? Sounds like your setup tune or wiring of coils are not correct. There wont be a direct answer but Id maybe talk to the guys at efi connection who specialize this swap that can guide you to fix the issue. But you haven't answered what things have you done to verify proper timing and no spark.
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Yes coil on plug swap. Set the timing the same way I set it when I was running the 4x setup. Tdc compression stroke, balancer Mark lined up with Mark on timing cover. Distributor rotor dent lined up with distributor housing Mark and drop right it pointing at the 8. I have yet to verify if ecm is sending the signal to fire coils. Then I can rule out ecm. My cam and crank sensors are not seeing 12v. They are reading 11.5.
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Verdad Gallardo Looks like you already know the next step is to see if your getting signal to the coils. You need to verify not just 12v to the sensors but reference voltage to the ecm, then see if your getting signal to the coils while cranking. If the tune isn't setup correct either then you're chasing your tail.
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Its been a while since I did the coil on plug conversion on my L31 but I remember having a similar problem. I believe the instructions/pinouts had me swapping wires for the crank sensor or something, when I put them back to stock everything worked.
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Where did you get the wiring information from?
I seem to recall there being a few pins off between the f body and truck PCMs.
What cam position sensor are you using?
I never did a swap like what you're doing but I have done a Gen 3 to Gen 4 swap and ran into a problem that required the cam sensor plug to be wired different.
I seem to recall there being a few pins off between the f body and truck PCMs.
What cam position sensor are you using?
I never did a swap like what you're doing but I have done a Gen 3 to Gen 4 swap and ran into a problem that required the cam sensor plug to be wired different.
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I used the 99 02 ls1 f body schematics. For some reason if I disconnect crank or cam sensor it doesn't throw a code for it. I segment swapped the 02 LS1 engine and eng diagnostics and system into my truck tune but still nothing. Realigned reluctor and it's dead centered. Using cam sensor 10490645. And crank sensor . Dr6200. I'm thinking about going back to 4x as I can't get this set up to run which would really suck but damn I thought it was gonna be plug and play . I need some help.
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