- Help, I have a Detroit series 50 in an MCI MC-12 coach. Engine starts and idles, but has no power. Bus will limp while idling.
Full coolant, no water in oil, engine ran with alternator belt removed code 61 still present, no noticeable blowby etc..
Flashing codes
54, 61, 14, 16, 23
I'm heading out to have a look in the morning. Taking fuel filters, gas can to test engine return for air and good flow. I also have a DDEC II sensor testing kit. Without any software, is there a way to narrow down the code 61 trouble? If no any way to check all injectors?
Detroit 50 series idles but no power
- Thread starter samdland
- Start date
All of your codes have a common theme...voltage.
Start by ensuring the engine block is grounded properly. You can temporarily test this by hooking one side of some jumper cables between a good solid engine part and the negative post on one of your batteries. Likewise..check the wiring between the ECM and the batteries and there should be a couple of small blade type fuses on the wires at or very near the batteries..make sure they are both good (not 100% sure MCI did it this way..most trucks did). Testing for proper voltage at the ECM without a scan tool involves back probing ECM terminals...unless you really know what you're doing...this is risky as it is VERY easy to damage things (don't ask me how I know).
With the engine running...what voltage is at the batteries? Anything below 13 or over 14.8 on an older DDEC when running will usually start to throw codes..61 usually being one of the first. 61 is "injector response time long"...low voltage will cause this faster than an actual injector problem.
Early DDEC systems were very voltage sensitive....and you can spend hours chasing mechanical problems that aren't real.
Start with the basics...good proper operating voltage and good proper engine grounding...it'll likely solve at least 90% of your issues.
If you own this bus..or work on it frequently...look online for an old used Pro-Link scan tool with a Detroit cartridge. These things became pretty obsolete after DDEC5...but hung around for many years because they were simple, reliable and did 99% of the work you needed to fix most problems. With a DDEC 2 you don't even need one with the fancy card style back. You can also get Allison cartridges for them that may also talk to the transmission if it's an electronic auto.
They look like this.
Good Luck!
Start by ensuring the engine block is grounded properly. You can temporarily test this by hooking one side of some jumper cables between a good solid engine part and the negative post on one of your batteries. Likewise..check the wiring between the ECM and the batteries and there should be a couple of small blade type fuses on the wires at or very near the batteries..make sure they are both good (not 100% sure MCI did it this way..most trucks did). Testing for proper voltage at the ECM without a scan tool involves back probing ECM terminals...unless you really know what you're doing...this is risky as it is VERY easy to damage things (don't ask me how I know).
With the engine running...what voltage is at the batteries? Anything below 13 or over 14.8 on an older DDEC when running will usually start to throw codes..61 usually being one of the first. 61 is "injector response time long"...low voltage will cause this faster than an actual injector problem.
Early DDEC systems were very voltage sensitive....and you can spend hours chasing mechanical problems that aren't real.
Start with the basics...good proper operating voltage and good proper engine grounding...it'll likely solve at least 90% of your issues.
If you own this bus..or work on it frequently...look online for an old used Pro-Link scan tool with a Detroit cartridge. These things became pretty obsolete after DDEC5...but hung around for many years because they were simple, reliable and did 99% of the work you needed to fix most problems. With a DDEC 2 you don't even need one with the fancy card style back. You can also get Allison cartridges for them that may also talk to the transmission if it's an electronic auto.
They look like this.
Good Luck!
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