Engine/Transmission (1998.5 - 2002) Codes, reading them

[Alexdring]

So i have a 2002 CTD six speed 4X4. I have been getting the "dead pedal" where nothing happens every now and then if you mash the throttle. This weekend a friend of mine noticed that it will snap out of it either right at 1500rpms or shortly after. When it goes into dead pedal it is usually after maintaining a speed for a while like cruising. Its never happened during acceleration. Some times you can get it to come back by pushing in the clutch.



So i did the code test by cycling the key three times and these are the codes I got in this order, it was cold when i did the check by the way:



PCU:

0500

0460

1694

1693

1687



ECU:

0216

1693



Can someone help me with what these codes mean?

 

[JLandry]

P1693 <- Ignore this one



P0500 NO VEHICLE SPEED SENSOR SIGNAL

When Monitored:

Engine Temperature greater than 104 deg F, MAP vacuum approximately 159 to 169 inches of mercury and Engine RPM between 1400 and 3000 rpm.​

Set Condition:

No Vehicle Speed Signal for more than 15 seconds on two consecutive trips.​

P0460 FUEL LEVEL UNIT NO CHANGE OVER MILES

When Monitored:

Engine running and fuel level either below 15% or above 85% of capacity.​

Set Condition:

The PCM sees low fuel, less than 15%, for more than 120 miles or fuel level does not change by at least 4% for more than 250 miles.​

P1694 NO BUS MESSAGES RECEIVED FROM COMPANION MODULE



P1687 <- Can't find in Dodge Diagnostic Procedures Manual



P0216 FUEL INJECTION PUMP TIMING FAILURE

When Monitored:

Ignition on.​

Set Condition:

Engine speed >300 RPM, fuel command 5mm3/str, timing command must be within a certain window.​

I'd start by reseting all these codes (just buy a good code scanner to do this) then see which one's come back, then start addressing them.



With the accelerator pedal issue you've been experiencing, the P0216 code *could* be related, or it could simply be your APPS is failing. A P0216 code can be caused by low fuel pressure at the inlet to the VP44 injection pump. This can be caused by a dirty fuel filter or a failing lift pump. Do you have a fuel pressure gauge?



The P0500 code might mean you have either a wiring harness problem between the PCM and the speed sensor located in the rear axle, or the speed sensor itself is failing.



Good luck,



John L.

 

[Alexdring]

Interesting, thanks. No I dont have a fuel pressure gauge, I have no gauges yet, just bought the truck.

 

[JLandry]

Interesting, thanks. No I dont have a fuel pressure gauge, I have no gauges yet, just bought the truck.

If you don't want to spring for a set of in-cab gauges yet, at least get a fuel pressure test gauge so you can verify the VP44 fuel injection pump is getting adequate fuel. This is an example of fuel pressure test gauge:



#ad




VULCAN PERFORMANCE - FUEL PRESSURE TEST KIT



In the mean time, if you don't know the last time it was done (or it wasn't done recently), go ahead and replace the fuel filter.



Best regards,



John L.

 

[Alexdring]

So I should test at idle, half throttle and full I assume? Should i snake this into the cab somehow and test in real world driving if I can. If its my lift going out I should not drive it until I am sure right, just in case is does go out and takes the vp44 with it

 

[JLandry]

So I should test at idle, half throttle and full I assume? Should i snake this into the cab somehow and test in real world driving if I can.

Yes... you would hook up the gauge, then for a first rough-cut test, start the engine and see what the fuel pressure is at idle. Ideally it should be about 15 psi or a bit more, but the reading can vary depending on the condition of your fuel filter and lift pump. NOTE: You NEVER want to see it drop below about 4 or 5 psi as an absolute minimum, as this can be damaging to the VP44 injection pump.



If it's very low at idle, as in 5 to 7 psi, then there's probably no need to go for a test drive because the pressure will surely drop below 5 psi with much throttle. You can even rev up the engine a few times (after it's warmed up) to see what happens to the fuel pressure. In any case, you'll want to figure out why it's so low at idle before you go any further. I'd recommend you first replace the fuel filter and see what happens. If that doesn't correct the problem, then I'd probably replace the lift pump next. I'm partial to the Airtex brand replacement lift pumps because they're a reasonable cost ($169. 99 delivered from Diesel Distributors USA), install easily in the same location as the original, and have excellent pressure... 18 psi on my truck at idle, no less than 7 psi at full throttle and high engine rpm.



If that still doesn't fix the problem, then you'd start looking for fuel restrictions. The in-tank pickup screen could be plugged or a fuel line could have an air leak.



Now assuming you find acceptable fuel pressure at idle, you can drape the fuel pressure test gauge line over the driver's fender, then gently close the hood so the safety latch catches but the hood isn't completely locked closed in order to leave room for the line coming out from under the hood. Open the driver's window a bit and route the gauge through the window into the cab where you can read it during a test drive.



During the test drive, as long as the fuel pressure remains above 5 psi at full throttle, then that's acceptable. More fuel pressure is better... up to a point of course. From what I've read, most folks here on the TDR seem to accept 20-22 psi as the upper limit. With a stock lift pump you won't get anywhere near that though. 15 psi is supposed to be ideal because that's what the VP44 is supposedly calibrated at when on the Bosch test stand.

If its my lift going out I should not drive it until I am sure right, just in case is does go out and takes the vp44 with it

Yes. DO NOT operate your truck with fuel pressure below 5 psi as it could damage the VP44, and a VP44 costs well in excess of $1000!



Best regards,



John L.

 

[Bob Cochran]

Some instead of routing throw the side window tape to the windshield it that would work for you better.

 

[Alexdring]

Does anyone know why it would snap out of it around 1500 rpm? Does the computer start to by pass sensors? I wonder if the fuel system does anything different around that rpm. Its like a light switch its so apperant.

 

[JLandry]

Does anyone know why it would snap out of it around 1500 rpm? Does the computer start to by pass sensors? I wonder if the fuel system does anything different around that rpm. Its like a light switch its so apperant.

Well it depends on what could be wrong, but I can think of a couple of scenarios which could cause this...



The APPS (Accelerator Pedal Position Sensor) could have a faulty output below 1500 rpm.



The VP44 injection pump's internal timing mechanism could be sticking (which is a common failure).



I suggested you reset the DTC's and verify fuel the pressure first in order to start eliminating simple and common problems. It's important to see what DTC's (if any) come back as they can help narrow down where the problem is. In the absence of any DTC's and if the fuel pressure tests OK, I'd consider replacing the APPS with an aftermarket sensor purchased from TDR member Timbo. If that doesn't solve the problem, then you're likely looking replacing the VP44.



Let us know what you find out on your fuel pressure.



Best regards,



John L.

 

[Bob4x4]

The 1687 and 216 both point to the vp44,confirm fuel volume but order the vp now



Bob

 

[SSolderitch]

I am in the same boat, I get the following codes:

1693 - jtec companion module - is that the ecm? or the pcm?



602 - fuel cal. - i have rv275's?



500 - speed sensor - new sensor or bad wiring? how di I check? price of sensor?



1694 no ecm buss - do I need a replacment ecu? wires were checked? dealer reflash ok after loss of wait light, etc, but smarty load a no-go?

 

[Dave Zuber]

APPS or Cruse?

I'm the buddy trying to figure this out.



When it shows the dead pedal problem below 1500 rpm. You can lock in the cruse control and then use the accel button. It still doesn't accellerate. Doesn't this show that the APPS might be ok and the problem is elsewhere?



Also, if you keep it above 1500 rpm, the pedal is smooth and responsive. The truck runs out great and pulls hard to redline. There are no flakey spots in the pedal (like my 01).



BUT, if you let it decell until it's below 1500, then the pedal goes dead again. It's not totally dead, you just get 1/50th of normal power. Every time it gets to exactly 1500 rpm, then you get full power.



I was talking to a mechanic at Cummins NW (Colburg). He had not heard about anything like this. He said to bring it on down and hook it up to the engine dianostic and see what that shows. Minimum charge about $109.

 

[JLandry]

I'm the buddy trying to figure this out.



When it shows the dead pedal problem below 1500 rpm. You can lock in the cruse control and then use the accel button. It still doesn't accellerate. Doesn't this show that the APPS might be ok and the problem is elsewhere?

Dave,



No... this would not indicate the APPS is OK. The speed control uses a vacuum servo connected to the APPS via a cable to essentially duplicate what you do when you push on the accelerator pedal.



If you want to rule out the APPS, then you'll need to do this:



First remove the APPS assembly from the engine. This is pretty straight forward and simple, just be careful when you pop the throttle, speed control, and transmission cables off the bellcrank assembly. There's a ball on the cable ends which snaps straight off away from the post. If you try to pry the ball off from only one side, it likely won't come off. You'll see what I mean when you get a good look at it.



Once you have the APPS assembly off the engine, use a cheap analog multimeter to measure the resistance (Ohms) between pins 3 and 4 of the APPS connector. The specific resistance isn't critical... you're looking for a smooth steady increase in resistance from idle to full throttle.



If you see fluctuations, skips, or change in the rate of resistance increase, that would confirm the TPS (Throttle Position Sensor) is bad. A replacement can be ordered for around $160 from TDR member Timbo. Send him a private message. Dodge sells only the entire APPS assembly for over $500.

I was talking to a mechanic at Cummins NW (Colburg). He had not heard about anything like this. He said to bring it on down and hook it up to the engine dianostic and see what that shows. Minimum charge about $109.

It may be a worthwhile investment to pay for the diagnostic tests, otherwise you'll have to do them yourself or just start replacing things.



Good luck,



John L.

 

[darkhorse]

Dave,



No... this would not indicate the APPS is OK. The speed control uses a vacuum servo connected to the APPS via a cable to essentially duplicate what you do when you push on the accelerator pedal.



John. I believe the '02 6 speed has an electronic cruise control. My '01 sure does

 

[JLandry]

John. I believe the '02 6 speed has an electronic cruise control. My '01 sure does

Then I stand corrected!



Never mind me.



John L.

 

[CrewCabDiesel]

Alexdring,

You said you just bought the truck right? Was it from a dealer or private seller? The reason I am asking is that most dealers (and some private sellers) get carried away with pressure washing and might have soaked a few things they shouldn't. You have a lot of codes in a bunch of different systems, I would disconnect the batteries and start (carefully) unplugging different things under the hood and check for water and corrosion. Be sure to repack the connectors dielectric silicone to keep them dry. Also there is a major connector right behind the front driver’s wheel that controls all the systems you are having problems with, it’s right behind the inner fender and if it gets too wet you will have all kinds of problems (I found out the hard way at a car wash) and your over head console will even read CCD. Before starting to replace parts give this a try.

When I clean out connectors I use WD 40 to wash them out and air dry them, repack with dielectric silicone.

Be sure you reprogram your APPs after hooking up the batteries!

And get a 0 to 30 psi FUEL PRESSURE GAUGE rated for diesel ASAP!

Hope this helps

Kyle

 

[JLandry]

Dave,



What about this...



Since the truck had a P0500 (NO VEHICLE SPEED SENSOR SIGNAL) DTC, and since it has a fully electronic speed control (which references the Vehicle Speed Sensor), and since it doesn't accelerate under 1500 rpm with the speed control...



MAYBE the Vehicle Speed Sensor is faulty?



It's located on the rear axle differential housing. The Dodge part number should be 56028187AE.



Best regards,



John L.

 

[Bob4x4]

Should be fairly simple... ... ... . hook up a good scanner and go for a drive. If your problem is easy to reproduce you will be able to see what is happening.



Bob

 

[darkhorse]

(I found out the hard way at a car wash) and your over head console will even read CCD.

Please pardon my hyjack but I've seen that CCD on my overhead a few times & wondered what's up. It self corredts in a short time.

 

[LSchulz]

Also, if you keep it above 1500 rpm, the pedal is smooth and responsive. The truck runs out great and pulls hard to redline. There are no flakey spots in the pedal (like my 01).



BUT, if you let it decell until it's below 1500, then the pedal goes dead again. It's not totally dead, you just get 1/50th of normal power. Every time it gets to exactly 1500 rpm, then you get full power.

I'm having these exact same issues with my truck. I put in an APPS from Timbo, and the problem got a lot worse. At least before, it was predictable, but not anymore. I'll be playing around with it more, and checking various parameters with a multimeter when I get a chance.