March 28, 2024, 07:13:22 AM

News:


Mag marelli code 42 issue

Started by cookieman8772, March 09, 2019, 03:02:49 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

cookieman8772

I have a 1999 road king with the magnet marelli system.  Code 42 stays lit, starting is about 50/50. I found if it didn't start, a twist of the throttle before cranking usually does the trick. I changed the TPS, fuel pump and filter. Injectors. Crank sensor. Ecm. And check every inch of the harness. Once it runs, its rins great. I've seen lots of posts. But no real answers. When it doesn't start, it smells really rich.

Pirsch Fire Wagon

Camshaft Position Sensor
DTC 42 occurs only when the engine is running if the ignition module either does not receive a signal from the cam position
sensor or receives an unexpected signal. The engine may continue to run, but possibly be hard starting.

One of the more common codes for the MM
Tom

kd

Try swapping out the Engine temp sensor with a known good one.  When they act up you get the rich mix.  The ETS usually doesn't throw a code but could be from a related effect.
KD

Coyote

Quote from: PIRSCH FIRE WAGON on March 09, 2019, 03:38:09 PM
Camshaft Position Sensor
DTC 42 occurs only when the engine is running if the ignition module either does not receive a signal from the cam position
sensor or receives an unexpected signal. The engine may continue to run, but possibly be hard starting.

One of the more common codes for the MM

:up:

MM Code List
12 - MAP sensor 44 - bank angle sensor
16 - battery voltage 52 - RAM ecm failure
24 - front coil 53 - ROM ecm failure
25 - rear coil 54 - EEPROM failure
35 - tachometer 55 - other module failure
41 - crank pos sensor 56 - cam & crank mismatch (ghost code)
42 - cam pos sensor


cookieman8772

I am aware that the code is not set during cranking. I'm gonna try the head temp sensor. I just went out and tinkered. Removed the mixture screws, which were bottomed out btw, I took them out and cleaned the passages. reinstalled them at 2 turns out on the front and 3 out on the rear. I am also aware that this is a common issue with these. But what I don't ever see, is a solution.

cookieman8772

Quote from: kd on March 09, 2019, 03:39:05 PM
Try swapping out the Engine temp sensor with a known good one.  When they act up you get the rich mix.  The ETS usually doesn't throw a code but could be from a related effect.



Will it test run without it or will it default to-40?

rigidthumper

CMP (cam position sensor) tells the ECM which cylinder is on compression stroke, so it fires the right one.  If the CMP is failing, the bike has a 50/50 chance of starting. If it's the original, it's over 20 years old. Time for a new one.
Ignorance is bliss, and accuracy expensive. How much of either can you afford?

cookieman8772

Quote from: rigidthumper on March 10, 2019, 10:29:13 AM
CMP (cam position sensor) tells the ECM which cylinder is on compression stroke, so it fires the right one.  If the CMP is failing, the bike has a 50/50 chance of starting. If it's the original, it's over 20 years old. Time for a new one.

It's new. Twice now. Got a faulty one first time. Gonna try the temp sensor. It's only money right?

rigidthumper

So, you've replaced the CMP (cam position sensor) and the CKP (crank position sensor)? I'd suspect the connection at the pins, where the sensors plug into the bikes wiring harness, next. Under the right side cover.
Ignorance is bliss, and accuracy expensive. How much of either can you afford?

smoserx1

March 11, 2019, 05:39:41 AM #9 Last Edit: March 11, 2019, 05:50:47 AM by smoserx1
 :agree:

Been there done that.  There was a service bulletin out about this connector and water intrusion.  Actually the connector on this model is under the right side frame rail near the rear brake pedal, right where it is exposed to moisture and road hazzards.  I ignored the service bulletin until I had to get towed home twice after a heavy rain.  Eventually the water intrusion causes corrosion.  The solution was to take the connectors apart, inspect/correct any corrosion, and pack the female housing with dielectric grease.

A couple of years ago I found one of the connector halfs on my 99 FLHT was cracked.  I replaced both of them.  If you go to ebay and search 74108-98BK and 74118-98BK you will find these connectors readily available.  I know the ones sold by NAMZ are the actual Deutsch parts, not knockoffs.  And one of the nice things here is the connectors that are supplied with these use open barrel (Weatherpack) crimps.  That means they do not require that special solid barrel crimping tool that costs as much as your house payment, and the tool can be obtained at about any auto parts store for about 30 dollars.

Try servicing the connector and filling it with grease first and see if that clears things up.

cookieman8772

Quote from: smoserx1 on March 11, 2019, 05:39:41 AM
:agree:

Been there done that.  There was a service bulletin out about this connector and water intrusion.  Actually the connector on this model is under the right side frame rail near the rear brake pedal, right where it is exposed to moisture and road hazzards.  I ignored the service bulletin until I had to get towed home twice after a heavy rain.  Eventually the water intrusion causes corrosion.  The solution was to take the connectors apart, inspect/correct any corrosion, and pack the female housing with dielectric grease.

A couple of years ago I found one of the connector halfs on my 99 FLHT was cracked.  I replaced both of them.  If you go to ebay and search 74108-98BK and 74118-98BK you will find these connectors readily available.  I know the ones sold by NAMZ are the actual Deutsch parts, not knockoffs.  And one of the nice things here is the connectors that are supplied with these use open barrel (Weatherpack) crimps.  That means they do not require that special solid barrel crimping tool that costs as much as your house payment, and the tool can be obtained at about any auto parts store for about 30 dollars.

Try servicing the connector and filling it with grease first and see if that clears things up.





Removed connector. Pin fit felt ok. But I hardwired it direct anyway. No improvement. Going to try the temp sensor next weekend.