No spark after engine swap

Tiny
JOELZAK7379
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  • 1999 DODGE DAKOTA
  • 3.9L
  • V6
  • 4WD
  • MANUAL
  • 250,000 MILES
I did a motor swap, nothing different than the original. Now I have no spark and I have replaced everything but the wiring harness.
Monday, December 20th, 2021 AT 10:18 AM

27 Replies

Tiny
JACOBANDNICKOLAS
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Hi,

As far as no spark, did you use the original distributor or the one that came with the replacement engine? I ask because there is a pick-up coil in the distributor that functions as a camshaft position sensor. If it is bad, you won't get spark. (See pic 1)

Next, is the crankshaft position sensor good or has it been replaced? See pic 2

Last, are you getting power to the ignition coil? With the key on, there should be power to the dark green wire with an orange tracer. Check that as well. See pics 3 and 4.

Also, if you have a live data scanner, see if there is an RPM signal when the engine is cranking and let me know.

Let me know.

Joe
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Monday, December 20th, 2021 AT 8:07 PM
Tiny
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Thank you for your reply. My first attempt to start truck after engine swap I had no pulse at ignition coil or injectors. First I ran test on ASD relay that was good. I still replaced it, still no pulse at coil. Then I checked continuity from PCM pin 7. Signal wire to coil and it was good. Then I checked my ground and added a few more. Then I checked continuity from PCM to power distribution center (ASD Relay). Everything is, I then once again and several times more during the next series of tests would check for signal to coil. I replaced pick up coil, CSPS, Coil. I have replaced every component except wiring harness and ignition switch. I have my 5-v reference just no signal from PCM to coil or injectors. Every part I replaced at least four times. I need my truck and am at a loss.
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Tuesday, December 21st, 2021 AT 4:29 PM
Tiny
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I will say this my CPS the original one was slotted on one end maybe that's what the problem is. I replaced it four times and none of which were slotted. My tachometer does not move either.
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Tuesday, December 21st, 2021 AT 4:30 PM
Tiny
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I used the distributor that came with motor.
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Tuesday, December 21st, 2021 AT 4:32 PM
Tiny
JACOBANDNICKOLAS
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Hi,

First, please bear with me because I don't know for sure what all has been done.

First, I attached the powertrain management wiring schematics below. First, I highlighted everything related to the ignition. Then, I un-highlighted the things you checked.

Here is what I am left with. You have a 5v reference at the CKP. You have ground. Do you have a signal to the PCM from the CKP (pin 8 gray wire / black tracer)?

At the ASD, the light green with a black tracer should have voltage once the key is on. If comes from fuse 9 in the junction box and goes to the ASD and PCM pin 1.

The Dark blue with a yellow tracer provides ground via the ASD pin on PCM (pin 3). Does that wire provide a ground path with the key on?

The gray wire at the ASD gets power from fuse 3 in the under-hood fuse box. Is the fuse good and does that wire have voltage with the key on? If you look through the schematics, note that fuse 3 has a large splice where power can be lost.

If you have no signal from the CKP and it does have the 5v ref and ground, the sensor is bad or the violet wire with a white tracer is open.

If you have no RPM signal, it really sounds like the issue is coming from the CKP. You indicated no signal at the PCM from the CKP which would make sense that the violet wire/white tracer is open or not making a good connection between the CKP and PCM.

There is a good chance you have already checked these things. I just want to make sure we are looking at it from the same point of view.

Let me know what you find or if you have already done this. Also, if you find no power from the fuses, confirm the fuse is good but also check to make sure there is power to and from the fuse.

Take care,

Joe

See pics below/Note: I had to cut each page in half to make them readable for you. I did overlap them so you can follow from one to the next.
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Tuesday, December 21st, 2021 AT 5:11 PM
Tiny
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Thank you so much for taking the time to download schematics and explain in detail where you (someone who knows what they are talking about) the procedure as you described. I want to be perfectly clear I have no idea what I am doing. With that said I did check ground at CKP and for signal and it was good. At first the ground was not good I had ohms and if I remember right it's supposed to be zero or as close to it as possible.5 is acceptable. Please correct me if I'm wrong. I talked to dodge master mechanic on phone he was convinced the crankshaft position sensor was the issue. So much so he bought me a new one from dealer telling me it will come with a spacer on the end of it which will be knocked off as I crank the motor then the gap will be correct. Except the new sensor did not come with any such thing nor did it fix it. I will check again and keep you informed as I do it in the next couple days. Thank you for your knowledge I appreciate it so very much.
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Tuesday, December 21st, 2021 AT 6:40 PM
Tiny
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I don't remember if I mentioned this yet, no codes. I have cranked it enough, so the engine has rotated several times.
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Tuesday, December 21st, 2021 AT 6:52 PM
Tiny
JACOBANDNICKOLAS
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Hi,

The funny thing about a crank sensor is it can fail and not set a code. LOL Anything to make it more difficult.

Take a look at the pic below. Also, before you jump into a lot of testing, make sure power is where it needs to be.

Also, you indicated you don't know what you're doing. Based on your first post, I find that hard to believe. You are on the right track. Hang in there. We'll figure it out.

Take care and let me know what you find.

Joe
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Tuesday, December 21st, 2021 AT 8:16 PM
Tiny
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Joe, hope you had a good Christmas. We got a foot of snow last night and it continues to come down. I'm going to give it a day or two before I get back to it. I will be in touch.
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Sunday, December 26th, 2021 AT 1:01 PM
Tiny
JACOBANDNICKOLAS
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Hi,

Ugh! A foot? I'm in PA, so I certainly know what snow is like. However, we haven't had that much in years, and I don't miss it. LOL

You take care and be careful. When you can, let me know how things are going for you.

Joe
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Sunday, December 26th, 2021 AT 8:44 PM
Tiny
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I got a circuit tester I removed ASD relay and checked each pin. (Green light =ground, red light=power) the always hot was hot the pin that distributes power to injectors was green and the rest of them were green with key off. When I turned the key on, and light turned red on the ignition pin. The pin that is the ground for ASD relay did light up green but very dim. My question is, why are all pins green until I turn key, and why is the only pin that should be green or ground so dim?
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Sunday, January 2nd, 2022 AT 6:04 PM
Tiny
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The engine I installed was painted BTW with cheap paint that's flaking off.
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Sunday, January 2nd, 2022 AT 6:06 PM
Tiny
JACOBANDNICKOLAS
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Hi,

If the key is off, the only wire that should have power is the gray one. The light green wire with a black tracer will get power when the key is in the run or start position.

The dark blue with a yellow tracer gets a ground path from the ECM. If it is dim, there could be a corrosion issue in the connector at the PCM. The dark green with an orange tracer has nothing until the relay energizes. At that point, the switch in the relay closes and power runs from gray wire through the relay and out the dark green/black wire to the injectors and other components.

Is that what is happening? Take a look at pic 1 below. Sorry it's so poorly labeled. I placed a + on the power supplies to the ASD relay. The gray wire is always hot and receives a ground through the injectors. The light green gets power with the key on and finds ground through the ECM.

Let me know if that is what you find. Also, confirm the ground (dim light) isn't pushed in, corroded, or damaged in any way.

Let me know.

Joe
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Sunday, January 2nd, 2022 AT 6:51 PM
Tiny
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With the key off all wires except for grey wire will show ground other words green light on my circuit tester.
It has a red light for power and green for ground. I just want to make sure we understand each other. Yes, the light turns red when I turn key on. I have code p0340 I replaced pick up coil again and checked continuity on every wire in my harness I inspected each plug. I don't understand why there is no spark. Everything worked great before. I don't get it, I'm extremely frustrated and need some fresh eyes.
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Tuesday, January 4th, 2022 AT 3:00 PM
Tiny
JACOBANDNICKOLAS
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Hi,

With the key on, the light should have two power supplies turning it red, the gray wire and the light green/black wire. If that is the case and the dark blue/yellow receives ground to the ECM, that should cause the switch (relay) via electromagnetics to close and send power to the injectors. Again, if there is ground via the dk blue/yellow, power to the gray and power to the green wire/black tracer, the relay should close sending power out the dark green/orange wire to the injectors. Are you getting power to the injectors? If not and the wires mentioned are functioning properly, either the relay is bad, there is a bad connection at the relay, or the dark green/orange wire has an open circuit.

Since you are getting a dim green light for ECM ground, that is where the problem likely is located. Now, it could be a pin in the relay box, partially open wire, or the ECM itself.

Try this. Take a jumper wire and jump the two wires circled in yellow to see if the injectors get power.

Let me know what you find.

Joe
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Tuesday, January 4th, 2022 AT 5:43 PM
Tiny
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I get power to injectors and coil. The only thing that seems to be off is I have no pulse at coil when I crank and no injector pulse I checked every wire and no open circuits. Grounds except for the dim light on ASD relay all check out just fine (0 ohms) I have no idea what I am doing.
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Monday, January 24th, 2022 AT 3:17 PM
Tiny
JACOBANDNICKOLAS
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Hi,

If you have power to both and no pulse, it is related to the crankshaft position sensor. See pic 1 below.

Here is how it works. The coil/inj has 12v at all times. They receive ground via the PCM based on CKP information (along with other things). If you have no pulse, the PCM isn't providing the ground path. So, either all the ground leads to the PCM failed at the same time, the PCM failed, there is no connection between the PCM and the injectors, or there is something missing to create the pulse.

When you replaced the CKP, where did you purchase it from? Was the connector and wiring to it good? It's near the exhaust manifold, so the heat can cause wiring problems.

Here is what I need you to do. Go back to the crankshaft position sensor. Unplug it and locate the violet wire with a white tracer. With the key on, there should be a 5v reference. If there isn't, next we need to locate a splice. It is a splice (S107) in the engine harness, rear of the engine. If there is no power to the sensor, there is a good chance that the splice (which is known to corrode and fail) was damaged when the engine was removed and replaced.

You will need to open up the harness to locate it. Locate the violet/white wire in that harness and follow it to the splice. Inspect it for corrosion, damage, loose wires, and anything that can prevent a good connection. If it appears good, check at that point for the 5-volt reference.

If you do originally find a 5v reference at the sensor, test the black wire with a light blue tracer at the same connector for a signal ground, key on. If you don't have ground, in the same wiring harness there is a splice (S103). Do the same thing. Open the harness, locate the black/lt blue wire and check it at that point for signal ground. Again, the key must be on.

Once you get to that point, let me know.

If both wires check good, let me know. Also, let me know where you purchased the CKP. I have seen so many faulty parts being sold.

Pic 2 below shows CKP, Pic 3 shows power splice, pic 4 shows signal ground splice.

Take care,

Joe

See pics below.
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Monday, January 24th, 2022 AT 4:08 PM
Tiny
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Joe, thank you again for taking the time to send me this detailed message. Now I want to start, just I want to start by saying this from the very beginning. I thought the crank position sensor was the faulting component, which was creating no pulse from the gate, I thought that now the reason for that is because well the original one that was on my motor to begin with which was good. It was damaged when I put the engine in for the first time. Now you have she must be thinking the first time how many times you do it? Well, I did it more than once, I did it twice; the first time I damaged the crankshaft position sensor. I was like well, I should have waited to install that. Because you know it's a very small hole there on the bell housing for it to fit into. Well, anyways I damaged it. So, what did I do? I did something I took it the crank position sensor I had from the motor I bought which came out of the automatic transmission mine's a manual I did not realize the size difference. Now, keep in mind I waited to put it in until after I installed it the second time made sure everything was all good that it does suck up nice and tight. So, I put the crank position sensor from an automatic transmission in my manual transmission okay, and I realized that the size was wrong. I was making contact to the bell, excuse me to the flywheel where it reads at that point I thought okay. Well, I need to go get a new sensor I wouldn't spend a hundred bucks on a new sensor at O'Reilly's my local parts store no difference nothing changed still no post I then contacted a friend of mine who's a Dodge Master mechanic and has been for 33 years his job for the last 22 years has been troubleshooting figuring out all the problems that people cannot figure out or have trouble figuring out.

He's the guy he told me it was the crankshaft position sensor. He told me he was so confident that he will go to on Chrysler's website and order the part out of his pocket because he's so confident that it will fix the problem and that there will be what it is called the hockey puck on the end of the center which will come off as the engine is rotated, but it will set it cap to the right gap so I was like okay, sure, because all the sensors I've dealt with up to that point none of them has had this spacer/hockey puck or whatever they call it on it now I get that sensor from him he sent it to me whatever and it doesn't have no grommet it has no hockey puck it has no space it has nothing on it but I compare it to other ones I've got from junk yards because I want to be absolutely sure that I got the right sensor and yes I gave up my VIN number. I gave up all the information on the pickup truck so I would be sure that we get the right sensor again he brought it through Chrysler the sensor. I have in right now is from Chrysler so when I received this sensor, I opened up the box I see that there's no grommet there's no nothing on it. I'm thinking okay, so I compare it to one that is that I pulled out of a truck in the junkyard which is identical to my truck everything is identical the matched up perfectly. Yes, and if you're wondering how I made an automatic one work in a manual truck yes, I modified the plug on the sensor not my harness so it would work. Yes, I did that so again I was that's my that was my go-to right there right at the gate. I thought it was the crankshaft position sensor so since then I've replaced it couple times the last one being from Chrysler themselves and still no difference, nothing changes still no pulse. I got power I got my 5-volt reference everywhere I need to have it. I've checked all my splices and looked at every move of my wiring harness countless times. I've inspected each wire countless times. I can't even put a number on how many times I've inspected each wire my wiring harness. It is starting at my sensors when I say sensors, I mean my crankshaft position sensor and my camshaft position sensor/pick up coil. I can't tell you how many times I've checked these wires. There was one wire that didn't have continuity, but it went all the way down by transmission and I had since then replaced that wire otherwise everything checks out. I did some checks, some rent, some tests that's confirmed that my PCM was working like it should be.
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Thursday, February 3rd, 2022 AT 9:36 PM
Tiny
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I'm doing talk-to-text I hope that my text is making sense I kept proofreading it at the moment but whatever I'm so bear with me I've checked my harness numerous times I ran test with to confirm that my PCM is working great it working great it looks great it works great I got power to everything I just don't have no pulse and again from the gate I thought it was my crankshaft position sensor because well it was it was a no-brainer because I had the wrong sensor in there and I just put a little washers in there to create a gap through all the thing is the gap well you know better than me that we're talking about thickness of a fingernail you know what I mean anymore than that you're not going to get a reading and it's not going to have a pulse it's not going to get the signal from the PCM or or to the PCM so I've since then learned all this and and I know this so I'm I definitely made sure that I got the right sensor through Chrysler now that sensor I'm looking at your picture that you send me and it shows a gromit on there now The grommet I don't know what the ground is the words that go or whatever would I do know is my original crankshaft position sensor on the bracket that mounts to the engine block okay one of them was slotted for adjustment if that makes sense not both of them but just one of them in every sense or since then not one of them is been slotted for adjustment I have taken this little scope camera so I can see in that little hole and see where the crankshaft position sensors are sitting versus the flywheel it looks like it's sitting perfectly I have tried to establish what Gap I'm looking at and the Gap appears to be correct as well which is supposed to be 0.034 or something or 0.34 of it whatever some number I can't remember exactly what it was but I did check all that and with the microscope whatever and all that stuff in my cap appeared to be correct my Gap not cap sorry but now that last message you sent me I feel like that's where I'm at with it as far as like now this is what I know since then this is what I've learned since then and I think I've shared this with you once my ASD relay the power distribution center I pulled off the relay I was just checking the you know the little pins in there whatever you know that always hot it was and with my circuit tester right I hooked into my positive on my battery my negative on my battery and I touched the always hot pain whatever you want to call it and it was bright red boom got power always all the time I went to the key on power only power only key on pin or excuse me I want you to the next one which was the one that tells my injectors hey go ahead power up and that was green for ground and it was very bright like wow that's got a good ground but I don't know if it's supposed to be green for ground so I went to the next one which is key on power power only with the key on and it's I believe that it was only temporary it doesn't with the key still on it doesn't stay powered up it just for a little bit comes on it was bright red it was great now mind you before I turn the key on that one as well was green bright green good ground I'm thinking of this one's supposed to be power on with only the key on why is it showing a ground with the key off I didn't make sense to me now I want you to understand that every single pin except to always hot one was ground before I turn the key on every one of them is green every single one of them including the always ground one okay now the thing is they were all bright green except the one that is the actual ground for that relay that one was green but very very dim okay I went to the relay next to it I think it's fuel pump or something like that in the same thing the always hot was red nice bright red okay the next one was Green really bright green the next one was real bright green and then the ground pin for that relay so pump was green but very dim so I was like okay hold on a second I can hear my fuel pump kick on when I turn my key to the right start position I know it's firing up but I'm not getting any pulse but I do know that on the other side of my power distribution center of my starter relay is working correctly because it cranks when I go to the start you know.
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Thursday, February 3rd, 2022 AT 9:42 PM
Tiny
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Okay so when I check the ASD relay with my circuit tester which I have connected to the hot on my battery and my negative on my battery and as I touch the pin that is supposed to be always hot it is always hot it's bright red it looks good the next one that sends my signal to my injectors and everything to let him know hey power up was I cycle the key that one is green for ground mind you I'm doing this with my key off it's green for ground it's bright green real good ground I'm like okay I don't think it's supposed to be green anyways I go to the next one that one is power only with the key on it's bright green ground mind you my key is off when I'm checking this and it's bright green bam good ground I'm like I don't think that's supposed to be green so I go to the next one which is my ground for that relay and boom it's green surprise surprise it's green just like it's supposed to be it's ground but it's very very dim I go to the next relay right next to it same thing I go to the relay below that same thing I go to relay below that one same thing I go to the relay on the other side of my power distribution center which is the starter relay and it's not the same thing you always hot pin is hot bright red the next one nothing the next one nothing the ground pin green bright green nice good ground which is nothing like the other side of my power distribution center which is all green except always hot and the ground pin is very dim green what would cause that what is that because I checked every wire in my harness for continuity I checked everything for 5 volt reference I got everything everything's tits what would be causing that a bad ground to the engine block I don't know I have no idea I do know that the engine block is painted with some cheap ass paint and I don't have a good ground to my engine block when I check my grounds unless I scrape the paint away
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Thursday, February 3rd, 2022 AT 9:50 PM

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