Miss When Warmed Up

[ThunderThighs]

New to the site and i know that this topic has probably cover dozens of times. I feel my issue is slightly unique than others covered on here.

Truck runs fine at operating temp of 190, until you down shift into a lower gear such as 2nd or 3rd and use that gear to hold you back going down a hill for a slightly longer period of time(or shut off for a few minutes it will start to miss as well). It starts to miss and rough idle this will continue until you can accelerate through the gears(miss will stick around until 1800 or so RPM). If it is shut off while missing you can come out the next morning and start it up it will still have a miss/rough idle.

 

I had it at a local diesel shop about a year ago they did all sorts of tests, charged me for 20 hours of labor fixing some wires and grounds in the fuse box area and then put a LP on it. Problem was never fixed, it started to miss on the way home.

 

Any help is appreciated!

[Mopar1973Man]

Welcome @ThunderThighs to the Mopar1973Man Web Site...

 

Ok. Lets start with basics then... Any error codes present? Just because there is no CEL doesn't mean there are stored codes. What is your fuel pressure at idle and under WOT operation? Let's make sure we are getting good fuel pressure. How many miles are on the truck? It's possible the injectors are plain worn out and need replacing. You might fill in your signature so other know what you have for a truck. 

[ThunderThighs]

The other day I read the codes with smarty: 

1693

0602

0463

01682

0122

Cleared the codes reset the apps by battery unplug etc. Uninstalled the smarty, drove till it got good and warmed up miss still shows up and no codes show up.

Fuel pressure is 16-18 at idle haven't had a chance to check at WOT, I have to get a longer hose for my gauge. 

 

Not sure if my signature is showing up: 

1998.5 Dodge 3500 210k manual trans 

Smarty tuner/BD air intake horn/cold air intake....truck was all stock when I bought it a year ago.

Edited December 14, 2017 by ThunderThighs

[Mopar1973Man]

 

[dripley]

Welcome to the site. Are you the original owner? 

[ThunderThighs]

No bought around a year ago, I have only put maybe 6000 miles on it.

 

p0122 I will try the APPS system test this weekend.

p0602 Some of the other codes such as fueling calibration, the smarty said that this was normal with a tune on it. Which is why I removed the smarty and it hasn't showed up again.

p0463 Fuel gauge only works from full to half at the moment was waiting to fix this when I had enough $ to add a fass or air dog system.

p1682 I have noticed right after start up the voltage gauge will take a few extra seconds to get up to 14. I probably should test the alternator.

Edited December 14, 2017 by ThunderThighs

[JAG1]

Have you made any progress toward a better running truck? Would like to hear about it.

[Mopar1973Man]

@ThunderThighs we are curious of your status on your truck.

[ThunderThighs]

Sorry it's been so long....holidays etc. Just got the pickup to miss and had the local shop put it on thier scan tool. They thought that when some smoke out of the exhaust smelled like fuel. They did an injector cut out an all were effected except number 5 so kinda leaning towards number 5 injector

[JAG1]

Important to get all new ones pop tested and flow matched. If they recommend just doing number 5 I would find another shop for sure.

 

 Do some pricing on your own to make sure they are treating you right on the cost. They should be... their cost a little over 400 bucks for all six.

 

Some others will chime in I hope to give you advice as the biggest problems arise more frequently from shops that do the least amount of work for the money. Watch out if they keep saying how much they are saving you 

 

Anytime you get a miss fire it's good to get new injectors first and foremost as you can do the most expensive damage not catching a bad injector.

Edited January 5, 2018 by JAG1

[ThunderThighs]

Agreed, I drove the pickup home that day parked it and started researching all new injectors. And will put them in myself.

 

I have never believed in just replacing one. I'll start fresh.