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5.7 efi tbi mercruiser no spark

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Williwill0902

New member
Hello everyone I'm new to the forum and having a no spark issue. My motor serial # 0l092658
Transom # 0l294350
Drive serial # 0l422426

My boat is a 99 vip vidicator
Boat started up fine a month ago but now it won't fire up. Cranks but won't start. Replaced battery. Checked spark with spark plug tester tool and no light. Checked with test light and I was showing power to coil and from coil plug that connect to the ignition control module. My good ol neighbor said probably bad ignition control module and to buy new coil just in case. Well I bought the coil and the ignition control module and it won't fire. Before I cancelled out the 2 new parts can someone help explain difference between a mercruiser marine coil $165 and ignition control module $250 between a autozone gm coil $25 and icm $40 parts. Icm looks identical plugged right in. Coil looked same but was missing braket riveted to coil to mount to motor, but also plugged right in. Im confused to what's the difference besides marine price being quite more. Since I see power from the plug coming from the coil before the icm my neighbor suggest the icm. After I replaced the 2 parts and to no avail I put the old parts back in. Now my neighbor thanks it's the distributor. Before I spend anymore money I would like your guys advice.and tips for testing to verify. I was also leaning towards the pick up coil in distributor. Im no expert with meter but when I tested the pick up coil I was getting weird readings and I was assuming I tested it to be bad but need help with meter. When I tested wires from pick up coil to ground with ohm meter set m I was seeing 13.8 m ohm. When I tested 2 leads together I was seeing range from 1.4 ohm m to 4.3 ohm. Services manual says I should see infinite when to ground and as close to 0 as possible when leads together. According to my test is the pick up coil bad? Sorry for the book, hope I explained everything well. Thanks
 
Thanks for putting up the serial numbers on your lump it's very helpful! Nobody does that and it always delays response.
First things first. Verify that plugs are properly gapped, that the wires from diz cap to plugs are in correct sequence, that you have good cap and rotor.
"Boat started up fine a month ago but now it won't fire up" well, that's pretty much the definition of a break down. So, what could have gone wrong? Probably something really simple. Make the checks noted above and then we will get into more detail.
 
I'd doubt there is any difference between the coils (other than price). On the ICM, I'd bet the expensive one is a Delco made part where the ICM from AZ is aftermarket.

Assuming the aftermarket ICM maker has a decent quality control system, the majority of the differences won't matter as your ECU control the timing once the engine is running...

You may find it more efficient to get the factory manual and do the troubleshooting to determine the real issue vs changing parts.....
 
o2batsea said:
Thanks for putting up the serial numbers on your lump it's very helpful! Nobody does that and it always delays response.
First things first. Verify that plugs are properly gapped, that the wires from diz cap to plugs are in correct sequence, that you have good cap and rotor.
"Boat started up fine a month ago but now it won't fire up" well, that's pretty much the definition of a break down. So, what could have gone wrong? Probably something really simple. Make the checks noted above and then we will get into more detail.
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Thanks for the reply. I'll check everything over you mentioned. Plugs should be in correct sequence because I only took one off. I did notice some damage to the rotor. Where it make's contact with pin in cap that part is worn down quite a bit, I asked neighbor's opinion on it and he believed it to be not bad enough to cause a no spark but I might replace it since I see damage and it's only a matter a time before it does fail, if it hasn't already. I'll try and take a picture after work. So as far as starting a month ago it was just in my yard with hose. I would start once a month during winter but the boats been out of water since September 18....
 
Williwill0902 said:
Thanks for the reply. I'll check everything over you mentioned. Plugs should be in correct sequence because I only took one off. I did notice some damage to the rotor. Where it make's contact with pin in cap that part is worn down quite a bit, I asked neighbor's opinion on it and he believed it to be not bad enough to cause a no spark but I might replace it since I see damage and it's only a matter a time before it does fail, if it hasn't already. I'll try and take a picture after work. So as far as starting a month ago it was just in my yard with hose. I would start once a month during winter but the boats been out of water since September 18....
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Rotors are a dime a dozen Replace it.
 
makomark said:
I'd doubt there is any difference between the coils (other than price). On the ICM, I'd bet the expensive one is a Delco made part where the ICM from AZ is aftermarket.

Assuming the aftermarket ICM maker has a decent quality control system, the majority of the differences won't matter as your ECU control the timing once the engine is running...

You may find it more efficient to get the factory manual and do the troubleshooting to determine the real issue vs changing parts.....
Click to expand...

So icm really won't cause a no spark? Thanks. And your absolutely right I don't want to throw money at parts before testing and confirming the part to be bad. My problem is I have basic mechanical skills and have a hard time with a multi meter. I tried testing ignition coil and I got a .08 ohm. I assumed it was good but was told to "grab one anyways". Do you know if I tested this correctly? Also the pick up coil in distributor seems to be testing bad but once again I can't confirm if I'm testing correctly? From coil wires to ground I was reading about 14.1 ohm. When I would test the 2 coil wires together it was 4.3 ohm. Ive been reading the mercruiser service manual 24 and it says test to ground and I should see infinite. Test 2 wires to each other and should be as close to 0 as possible. I see 4.3 ohm. So according to test wouldn't this mean pick up coil is bad? Sorry but I'm having hard time understanding the meter. But manual says if it test bad replace coil but I really want to make sure it's bad before I replace. Once again thanks.
 
A bad ICM can cause a no spark condition. you can read thru the details in the service manual you have.

Meter readings given i the manual were made with 'good' meters, typically high input impedance digital meters. not all meters have good accuracy on low impedance circuits (like the pickup coil).....the pickup coil should be isolated from ground - 14 ohms is not sufficient....maybe there's a multiplier on the meter you missed?? touch the two leads of the meter - note the reading and then measure between the two leads - note reading and then touch two lead together and not the third reading....if the first & third readings aren't the the same (plus or minus a count on the meter) then the meter may need a new battery....if the 1st & third readings are the same and the second is within an ohm of first, then the coil has adequate continuity..

anyhow, the manual has all the service data needed to diagnosis the system....except for the choke in the harness going to the coil.....when they fail, some people replace the harness and others just remove the choke..
 
Go to termo. Heat sensor starboard side on top of intake has 2 pin connector , unplug and see if motor starts. I've already asked this question. Is termo - sensor for iac valve (book don't tell) or is termo sensor. For over heat and enrichment for tks engine, they don't explain. Unhook plug at termo sensor if it cranks , that's your culprit.
 
Mikey N.C. said:
Go to termo. Heat sensor starboard side on top of intake has 2 pin connector , unplug and see if motor starts. I've already asked this question. Is termo - sensor for iac valve (book don't tell) or is termo sensor. For over heat and enrichment for tks engine, they don't explain. Unhook plug at termo sensor if it cranks , that's your culprit.
Click to expand...

What the hell are you talking about? Stop confusing the OP.
 
Dockside please tell me what sensor is 1/2 in pipe thread with 2 pin connector, starboard side just behind t stat housing, when unplugged have fire at plugs. Order from Donavan new termo sensor, installed bingo motor cranked. So please tell what is this sensor. Do I need to learn how to post pics. To show u ? You should know what I'm talking about?
 
I'm pretty sure my pick up coil is bad. I could not get a good reading. I bought a new one and when I test it I see ..084 ohm constantly.. so I decided to replace it . the star on the shaft for distributor was very rusted. Also the wheel with contacts was very rusted. I wanted to clean them up nice so I knew I'd be getting good contact. Problem is I had tough time taking out the shaft . I tried using 1/4 inch extension to tap it out. Well it was seized on there and when I gave it a nice hit the top bushing came out with the rod. I think I'm screwed with this distributor now and probably going to have to buy a new one. I'm gonna try and get this bushing off so I can try and clean the shaft up to try and put everything back together if possible but I don't know if I can break loose shaft from the bushing and if I do I don't know if the bushing will go in and function properly. I'm going to try and if I can't I guess I'll be ordering a new distributor. Times like this makes me wish I'd stop trying to fix everything myself and allow the pros to handle it. I was pretty sure that it was going to run after cleaning up the rust and replacing the pick up coil.
 
Got it back together after smoothing out shaft and oiling it up before installing. The bushing went in its place when I put the shaft in, locking into place and then I was able to remove shaft easily now where I was able to finish cleaning up the shaft. Got it all back together and hook meter up to coil leads and rotated and I was seeing small amount of voltage generating. After work tomorrow will be the real test when I put it back in the boat. I'll update after work tomorrow.
 
Williwill0902 said:
Got it back together after smoothing out shaft and oiling it up before installing. The bushing went in its place when I put the shaft in, locking into place and then I was able to remove shaft easily now where I was able to finish cleaning up the shaft. Got it all back together and hook meter up to coil leads and rotated and I was seeing small amount of voltage generating. After work tomorrow will be the real test when I put it back in the boat. I'll update after work tomorrow.
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Hook the distributor wires back up to the system, don't install it, hook up a spark tester to the coil power on the key switch and rotate the distributor shaft. If it sparks the tester and fires the injectors you can finish your install.
 
So install distributor, I already have wires still plugged to the cap. Hook up spark tester I assume from coil to top of distributor? When you say power on key switch just turn key to on without cranking? I have an off/run button and I have to have it on run to work. Or try cranking which will cause shaft to spin and spark? Sorry if it's a dumb question I just want to make sure I get it right.
 
If you already dropped the distributor into the engine, you will need to engage the starter to turn the distributor.

If you just hooked up the wires and turned on the key without dropping in the distributor, you could just turn the shaft with your hand.
 
Docksidemarineservices said:
If you already dropped the distributor into the engine, you will need to engage the starter to turn the distributor.

If you just hooked up the wires and turned on the key without dropping in the distributor, you could just turn the shaft with your hand.
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Thank you Dockside. I followed your instructions and sure enough I got spark. I put everything back together feeling dam confident it was going to get her to turn over, and she fired right up. Shut it down and fired right back up again. Only issue I'm noticing is she idling low. Not extremely low but lower than normal. I got to hook tachometer grey wire back up to see the rpm. I disconnected during troubleshooting. Budy going to bring time light to work tomorrow, while I'll do some reading tonight to make sure timing right. Any other suggestions for low idle?
 
Williwill0902 said:
Thank you Dockside. I followed your instructions and sure enough I got spark. I put everything back together feeling dam confident it was going to get her to turn over, and she fired right up. Shut it down and fired right back up again. Only issue I'm noticing is she idling low. Not extremely low but lower than normal. I got to hook tachometer grey wire back up to see the rpm. I disconnected during troubleshooting. Budy going to bring time light to work tomorrow, while I'll do some reading tonight to make sure timing right. Any other suggestions for low idle?
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Set the timing and see what you get. After timing is set, if idle is still low, check the IAC. Make sure it is clean and working, it controls Idle rpm.
 
Docksidemarineservices said:
Set the timing and see what you get. After timing is set, if idle is still low, check the IAC. Make sure it is clean and working, it controls

So I should have set the timing. I thought maybe I was off. I tried taking to the lake before heading out to the river and it ran like crap. I should of known by low idle and when I Rev up sounds week and now power. On the water had no power sputtered and sound like back fires. Pissed the family off and loaded up and went home and had to cancel river vacation. Any advise on what I should try? I'm not quite sure as the manual says to time buy obd tool but I don't see a port to hook up In my boat. Do I hook directly to ecm? Also could I have put distributor in wrong? It slid right in but when i would the rotor would turn off my mark a bit. I tried moving shaft with screwdriver a bit so it would line up but every time I dropped in the rotor still moved a bit off. Should I pull it, try rotating shafts other way and maybe when I drop in then the rotor will shift over to the correct marking?
Click to expand...
 
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