Kwdriver84

4-2 code driving me crazy please help!!!

Recommended Posts

Kwdriver84    2

I have a 97 mack ch-613 with a 350 engine. The electronic malfunction came on and I figured how to pull up the code which is 4-2 fan clutch output If I'm not mistaken.The light has a weird pattern from what I have seen sometimes its stays on for days and sometimes it cuts on and off through out the day. when its on I loose performance power and when it cuts off I get it back again. My fan works good and I don't see why I'm getting this code please help anybody!!!

  • Like 1

Share this post


Link to post
Share on other sites
turckster    66

You should not be loosing power on a vmac 3 with a 4-2 fault which is  fan clutch output. On  v-mac2  the fault is the road speed sensor. That would cause a loss of power while active.  V-mac 3 is the e-tech engine w/individual unit pumps while v-mac 2 is an e-7 engine with an inline injection pump.

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster I checked the engine plate it says e-7 330-350 and my I do have an inline injection pump. So the next question is "where is the speed sensor on this truck on the flywheel or back of transmission?"  I also found this speed sensors online what's the difference? Thanks 

image.png

Edited by Kwdriver84

Share this post


Link to post
Share on other sites
turckster    66

The speedo sensor is located  at the rear of the transmission. Measure the resistance of the sensor. If it is gold in color(old style) it should be between 200-300 ohms, if it is black and looks like plastic(new style) it should be 140-180 ohms.  If that is ok, remove the sensor and check the tip for damage, also make sure the tone ring does not turn (use a screw driver through the sensor hole and try to turn). If all looks ok, try reinstalling the sensor and make sure it is adjusted properly. Screw the sensor until it contacts the tone ring, back off 1 turn and lock it down. 

The gold colored sensor looks like the older style sensor Mack used to use, should be ok. 

Edited by turckster
  • Like 1

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster I ordered the speed sensor and finally got the light to go out and got power back on my truck. I appreciate your help/advice and hope this post helps more people out there. Thanks again buddy.👍🏽👏🏽

  • Like 1

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster I'm sorry for bother but I'm having an issue. My truck has been shutting off randomly and also going down the road. The lighting bolt comes on and gives me a 7-5 code then I able to crank right back up. Somet days it cuts off than others. I tried to find the codes for the v-mac 2 but no luck yet. Do you know what could be the issue? Thanks

Share this post


Link to post
Share on other sites
turckster    66

A 7-5 fault for vmac ll is the Rack Position sensor (current below normal or open).  Most likely the issue is a bad connection at the inj. pump to chassis harness connector.  While the engine is running try wiggling the harness and connector to see if the engine stumbles or dies. If so I would check the pins to see if there are signs of arcing or if they are discolored.  Sometimes the connector can wiggle lose and cause what you are seeing. Try to secure the connector the best you can using plastic wire ties.

If that is not the issue then the problem could be either the harness cord to the pump or inside the electronic side of the inj. pump. If it seems that the engine dying happens only when it is hot it might be a bad solder joint or bad rack position sensor.  If that is the case the governor housing will have to come off. 

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster I have unplugged it and cleaned it out and plug it back in and the problem goes away for 2-3 days and it starts again. If the plug is the issue can I just buy the plug and rewired the new one to it? Thanks 

Share this post


Link to post
Share on other sites
turckster    66
8 hours ago, Kwdriver84 said:

@turckster I have unplugged it and cleaned it out and plug it back in and the problem goes away for 2-3 days and it starts again. If the plug is the issue can I just buy the plug and rewired the new one to it? Thanks 

With the connector secured in the holder with wire ties, if you wiggle the harness does the engine  sputter or cut out intermittently? if no then the issue may be inside the injection pump governor housing. If yes, the best thing to do is crimp on new terminals and replace the chassis to inj. pump harness connectors. 

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster it's been a while since I posted an update. Well the truck didn't give me much problem during the winter season but somehow now that we got hotter temps and it's summer the truck has been shutting off on me more often. Finally Tuesday it left me stranded on the highway it didn't want to crank anymore and the same code came up 7-5. I had enough and took it to the mack place and now I'm being told I might need a new injection pump. Do you think if there's soldering issue inside the pump like you suggested does it need to be rebuild or is there a cheaper fix? 

Share this post


Link to post
Share on other sites
turckster    66

Fewer dealerships are repairing injection pumps anymore. Our pump stand finally broke down and the company decided to retire it. We rarely used it anyway here in the last 5 or so years. We rarely rebuild injectors because it's cheaper to replace with reman injectors. If we have to have a pump evaluated for repair we use a local injection pump service company. Most of the time we exchange inj. pumps w/reman pumps. The last in line injection pump rolled out of the factory about 20 years ago on a Mack. 

I can only assume that they see excessive wear or additional damage and that is why they may recommend exchange. You could remove the pump and have an independent pump repair shop look at the pump. It'll save you some money in labor and parts but since I work for a Mack/Volvo dealership I feel dealership work is better quality from a reputable dealership. 

Share this post


Link to post
Share on other sites
Hobert62    500

On my dads isx cummins when his pump went they said if the security  seal on the pump was broke they "can't" accept them for a core.  

Share this post


Link to post
Share on other sites
turckster    66
21 hours ago, Hobert62 said:

On my dads isx cummins when his pump went they said if the security  seal on the pump was broke they "can't" accept them for a core.  

For us (Mack/Volvo dealership) if the tamper proof seal was missing or cut then that would void the warranty (if one still existed). It would not affect core value. 

  • Like 1

Share this post


Link to post
Share on other sites
Kwdriver84    2

Well Mack place priced it at $2,600 taxes included and the rebuild shop said anywhere from $1,800-$2,200 to rebuild it. I went with the Mack place since it's going to be alittle faster to replace. It should be ready this week and hopefully that is going to take care of the whole 7-5 issue I had. I'll keep you updated. 

Share this post


Link to post
Share on other sites
Kwdriver84    2

@turckster well $3,300 later with a re manufactured injection pump. I drove home this afternoon with it and didn't have any issues. Went to get a load to the woods and it started to shut on me again giving the same code 7-5 and at one time it gave me 5-9. I managed to drive it out to the highway for a 80 mile load and 45 mile trip back home and no issues whatsoever. I'm thinking about driving it tomorrow to see what it does again. What you think @turckster?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now