mrmustang Posted July 7 Posted July 7 Let's take a giant step back, forget the path you are currently on and instead start with the very basics: Assuming both the fuel filter and the fuel have been swapped out: Do you have fuel at the injectors? If so, are the injectors low impedance or high impedance and what size are they? Do you have spark at the plugs? Have you done a compression check yet? I'm asking as reviewing past posts and this thread, you have not looked over the very basics of getting the engine to run. Or if you have, you have not mentioned it to the best of my knowledge.
MV8 Posted July 7 Posted July 7 (edited) Let's not. Compression sounds even. The starting system seems adequate. The ecm is getting power while cranking. The crank trigger is syncing. It won't sync if the engine is not turning. It looks like a previous owner bought the complete induction kit for a zetec black top that includes everything but the zetec crank sensor and coil packs. This would include their basic start tune for this application. You can contact them to check it or simply download the currently available tune (36 tooth, MAP based load) for this to compare, because 35% MX Time does not look right. It should be 50%. Also check your tooth control table. It starts with zero as a 5 and continues repeating 5445 and should be a 3 starting at tooth 35 and up. What are the sensor sensitivity settings? It will show the gain as high or low applied to the crank sensor (which is an AC volt gen and tach) above and below a certain rpm and if the trigger is rising or falling. Again, it is syncing but that is only part of it. Do you have power to the coils middle terminal during cranking? It would be interesting to see the timing setting. The "live" function allows you to see what is going on with just about anything but coil pack power. Edited July 7 by MV8 1
Clarko Posted July 7 Author Posted July 7 2 hours ago, MV8 said: Let's not. Compression sounds even. The starting system seems adequate. The ecm is getting power while cranking. The crank trigger is syncing. It won't sync if the engine is not turning. It looks like a previous owner bought the complete induction kit for a zetec black top that includes everything but the zetec crank sensor and coil packs. This would include their basic start tune for this application. You can contact them to check it or simply download the currently available tune (36 tooth, MAP based load) for this to compare, because 35% MX Time does not look right. It should be 50%. Also check your tooth control table. It starts with zero as a 5 and continues repeating 5445 and should be a 3 starting at tooth 35 and up. What are the sensor sensitivity settings? It will show the gain as high or low applied to the crank sensor (which is an AC volt gen and tach) above and below a certain rpm and if the trigger is rising or falling. Again, it is syncing but that is only part of it. Do you have power to the coils middle terminal during cranking? It would be interesting to see the timing setting. The "live" function allows you to see what is going on with just about anything but coil pack power. Hi just to clarify your first para to make sure we are on same page.. when cranking with starter… the stat sync stays OFF…. My understanding is that is BECAUSE it’s miss counting teeth and that causes the timing errors to keep rising …. So until I get SYNC, it will not produce fuel or spark…. the good news now of course is that we know if we turn the engine over by rolling it down a hill it DOES sync…. we just have to figure out WHY the starter throws the crank sensor for a six so badly!!!! I have Jerry rigged up a home made additional shield for the crank sensor lead (it was already a twisted shielded pair from Omex…. I used tinfoil, then painters tape, then a length of wiring loom and earthed the end of it to battery negative with my two Omex ecu earth wires…. Didn’t work! the search continues.
Clarko Posted July 7 Author Posted July 7 2 hours ago, MV8 said: Let's not. Compression sounds even. The starting system seems adequate. The ecm is getting power while cranking. The crank trigger is syncing. It won't sync if the engine is not turning. It looks like a previous owner bought the complete induction kit for a zetec black top that includes everything but the zetec crank sensor and coil packs. This would include their basic start tune for this application. You can contact them to check it or simply download the currently available tune (36 tooth, MAP based load) for this to compare, because 35% MX Time does not look right. It should be 50%. Also check your tooth control table. It starts with zero as a 5 and continues repeating 5445 and should be a 3 starting at tooth 35 and up. What are the sensor sensitivity settings? It will show the gain as high or low applied to the crank sensor (which is an AC volt gen and tach) above and below a certain rpm and if the trigger is rising or falling. Again, it is syncing but that is only part of it. Do you have power to the coils middle terminal during cranking? It would be interesting to see the timing setting. The "live" function allows you to see what is going on with just about anything but coil pack power. A couple of screen shots of the Omex software live readings… also… back in 2020 when I threw in the towel.. I had sent Omex the ecu to test on someone else’s car… and it came back to me as double checked and fully functional… so it is definitely something to do with me! And my setup.
MV8 Posted July 7 Posted July 7 (edited) Monitor the ecm input voltage with "live" or a dvm at the red wire and include "run time" for the ecm. What is it with and without the starter engaged? Does the run time reset when cranking? Also, Omex states that switching the leads on the crank sensor can mean the difference between sync or not even though rpm is indicated either way. Edited July 7 by MV8
Clarko Posted July 8 Author Posted July 8 2 hours ago, MV8 said: Monitor the ecm input voltage with "live" or a dvm at the red wire and include "run time" for the ecm. What is it with and without the starter engaged? Does the run time reset when cranking? Also, Omex states that switching the leads on the crank sensor can mean the difference between sync or not even though rpm is indicated either way. 👍👍 1
Clarko Posted July 8 Author Posted July 8 22 hours ago, MV8 said: Monitor the ecm input voltage with "live" or a dvm at the red wire and include "run time" for the ecm. What is it with and without the starter engaged? Does the run time reset when cranking? Also, Omex states that switching the leads on the crank sensor can mean the difference between sync or not even though rpm is indicated either way. Handed across my starter motor to the auto electrical place… They are going to source a different one that fits my application. Now I’m cleaning out my entire fuel system to get rid of 5 years of crud. will keep you guys a breast of progress 🙏
MV8 Posted July 8 Posted July 8 You could also sync test with the "MX Timing" set to 50% (from 35%) and check to see if the crank sensor to flywheel tooth clearance is within specification with the aftermarket starter mount plate thickness that could affect bushing location. A six inch dial or digital caliper can be used to check the depth of the hole (the end of the caliper extends into the bushing hole to touch a tooth).
Clarko Posted July 8 Author Posted July 8 50 minutes ago, MV8 said: You could also sync test with the "MX Timing" set to 50% (from 35%) and check to see if the crank sensor to flywheel tooth clearance is within specification with the aftermarket starter mount plate thickness that could affect bushing location. A six inch dial or digital caliper can be used to check the depth of the hole (the end of the caliper extends into the bushing hole to touch a tooth). Yes currently using 50 for Mx timing and Mx timing start.. have tried them both down to 20 and up as high as 75. I know some people have had issues with Omex getting sync because air gap between sensor and trigger wheel was too wide which is why I spent an inordinate amount of time adjusting the gap from 1mm to around 0.5 mm now…. And yes have switched polarity on the two wire sensor leads “ just in case” but but no joy. So my current thoughts are: Put in the new starter when it gets here… If no joy there… then connect everything up again and bump down hill to see if everything works… try increasing shielding on crank sensor wire even further and maybe shielding starter motor? Failing that its mounting trigger wheel on from pulley and fabricating a bracket for crank sensor for that… which is a slight pain as no one does a kit for it… ( don’t need to because the engine already has a crank position sensor housing there already
mrmustang Posted July 8 Posted July 8 2 hours ago, Clarko said: Handed across my starter motor to the auto electrical place… They are going to source a different one that fits my application. Now I’m cleaning out my entire fuel system to get rid of 5 years of crud. will keep you guys a breast of progress 🙏 Now you understand a bit more of where I was going. Trust but verify, or in other words, never trust the DPO's (dreaded previous owner) parts choices. Bill 1
Clarko Posted July 9 Author Posted July 9 38 minutes ago, mrmustang said: Now you understand a bit more of where I was going. Trust but verify, or in other words, never trust the DPO's (dreaded previous owner) parts choices. Bill Yes one of my favorite expressions Bill! 🤣🤣
Clarko Posted July 16 Author Posted July 16 On 7/7/2025 at 3:28 PM, MV8 said: Monitor the ecm input voltage with "live" or a dvm at the red wire and include "run time" for the ecm. What is it with and without the starter engaged? Does the run time reset when cranking? Also, Omex states that switching the leads on the crank sensor can mean the difference between sync or not even though rpm is indicated either way. Brief update: I installed the new starter motor today… and the good news that I got stat sync to come ON… but timing errors still climbing…. So I’m only HALF pregnant! so the new starter has improved things ( throwing off less emi) but I’m still throwing off enough interference to mess with the crank sensor reading ecu? Ill see what Omex suggests but am guessing I need to up my “suppression” game 🤷🏻♂️ IMG_3754.mov
MV8 Posted July 16 Posted July 16 Did you ever setup live to monitor the voltage cranking and run time? This would determine if your connections are adequate to power the crank sensor sufficiently through the ecu versus just enough for the ecu to stay on during cranking. Could also be checked with a jumper to the batt positive to the red wire. Looking to see how much voltage drop there is. 1
Clarko Posted July 19 Author Posted July 19 On 7/16/2025 at 2:58 PM, MV8 said: Did you ever setup live to monitor the voltage cranking and run time? This would determine if your connections are adequate to power the crank sensor sufficiently through the ecu versus just enough for the ecu to stay on during cranking. Could also be checked with a jumper to the batt positive to the red wire. Looking to see how much voltage drop there is. Here is a vid I shot yesterday showing voltage drop down to about 11.5 volts cranking so I believe that’s plenty of juice. I am messing about with ferrite beads and adding shielding to the starter motor and CPS cable but am thinking that I should give that up and move to a trigger wheel on the Crankshaft pulley to hopefully put this to bed so that I can move forward with the build 🤷🏻♂️ IMG_3788.mov
MV8 Posted July 19 Posted July 19 Looks good. I've not seen your wiring behind the engine, but the cps wires should be isolated from the others (specifically ignition coil and injector wiring) as soon as they exit the ecm. Being shielded or twisted is not enough. I've not seen your cps installation in the block, but the bushing needs to be aluminum with no ferrous metal around it near the sensor. 1
Clarko Posted July 28 Author Posted July 28 On 7/19/2025 at 12:48 PM, MV8 said: Looks good. I've not seen your wiring behind the engine, but the cps wires should be isolated from the others (specifically ignition coil and injector wiring) as soon as they exit the ecm. Being shielded or twisted is not enough. I've not seen your cps installation in the block, but the bushing needs to be aluminum with no ferrous metal around it near the sensor. Hi MV8, I was getting tired of nonsing around with ferrite beads and additional emi shielding, and have decided to go to a Crank pulley mounted trigger wheel to try and get rid of my issue once and for all. So I have some bits and pieces ordered up to make that happen. (Omex reckoned that moving the CPS that far away frm the starter should alleviate any issues 🤞) I will keep you posted, thank you so much for your help 👍🙏 1
Clarko Posted September 19 Author Posted September 19 On 7/19/2025 at 12:48 PM, MV8 said: Looks good. I've not seen your wiring behind the engine, but the cps wires should be isolated from the others (specifically ignition coil and injector wiring) as soon as they exit the ecm. Being shielded or twisted is not enough. I've not seen your cps installation in the block, but the bushing needs to be aluminum with no ferrous metal around it near the sensor. Hi MV8, so here is my latest update: For the first time ever the engine is now running in the car ! I did have a crank trigger welded to the crank pulley and moved the Crank Position Sensor to the front of the engine: Bingo! I do however now have the problem of a nasty noise coming from the starter motor / flywheel area… sounds like a bag of spanners rattling around! I switched the starter motor for another one… Worse! I am open to suggestions on how to diagnose exactly what that might be? I have the three bolts tight? How do I know if it needs shims etc?
7Westfield Posted September 20 Posted September 20 Pull the starter and check for marks on pinion or face of ring gear. Put a washer on each bolt, between starter and bellhousing and try it If the noise goes away, you have your answer 2 hours ago, Clarko said: How do I know if it needs shims etc? 1
MV8 Posted September 20 Posted September 20 (edited) I see you have marks on the flywheel ring gear from contact with the old starter gear. I also see where the engine block was ground away for starter clearance. Fabricated starter mount plates can have machining errors or generally sloppy enough to make things work properly. There are several things to check. Post pictures of the new starter gear , ring gear (where it can be seen through the starter window), and starter installed to show clearances. It could be the block was not ground enough for starter clearance. Ensure there is clearance between the engine block and the starter. Make the bolts finger tight, then you should still be able to rock the starter body back and forth on the mount plate a little. You should be able to rock it toward the block with the bolts slightly loose. If you cannot tell if there is clearance to the block, Use some play doh/ plasticine/ soft modeling clay on the block or starter, install the starter, then remove and look at the clay to see how thin it was squeezed out. Following on 7Wesfields suggestion, washers are typically too thick to keep the tooth engagement optimum, inconsistent in thickness, and so small in od that they don't evenly load the starter mounting flange. Take a sheet of paper and hold it over the starter mount flange with the edge up against the flywheel. Using a pencil or rub with your thumb over the sharp edges of the mount flange and bolt holes so they show on the paper. Cut the paper down to be a half circle shim. Cut out the holes with a hammer punch set (on ebay for gasket making and crafts). Trace the paper on to a cereal box. Make several tracings to make three shims out of the kraft paper that are flat (not burred up from cutting technique). Try different amounts of shim until the problem goes away, remove, measure the thickness with a six inch dial caliper (ebay for about $20) or take it to a machine shop to make your shim. I think an .050" sheet steel shim would be fine. You can buy the steel from home depot but it will need painting. You can also scan (not a pic-use a photo copier) the paper pattern and I will make you a couple .050" steel shims. It looks to be an 80s ford powered skidsteer/ 78-80 ford fiesta starter. Edited September 20 by MV8 1
7Westfield Posted September 20 Posted September 20 just to be clear, I suggested the washers as a test then make a proper spacer if needed 1 1
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