StakeMan

Discovered something interesting.

With the truck in park, rev the motor, and it has an intermittent miss.

So far, I have checked the MAP, replaced the IAT, changed the injectors. Fuel pressure is fine.

Anyone had this problem before?
If so, what was the cure?

RCW

I have seen the miss at idle caused by a defective CMP and/or CKP causing the timing to advance too far at idle. Sometimes just cleaning the CKP will solve the problem.

Air in fuel and dirty injectors are also common causes of a miss at idle. I would suspect the latter, because the last of the summer fuel is being pumped and there is a lot of old fuel being sold as they ready for winter blends.

jdeereboy

Does it smoke when it misses? Mine had a miss and smoked white smoke when the lift pump was low on pressure.

StakeMan

I have not checked the cam shaft sensor yet.

It does not smoke that I can tell when it misses.

KwikKurt

Have you set any DTC's???

StakeMan

No codes yet.

I cleaned, the connections on the VP pump yesterday. No change.

StakeMan

Update.

Just for grins I checked for codes via the key on sequence and got a P1693.

When I hook up my laptop to check the codes there are none. ???

RCW

Interesting, I thought overflows only happened to me. What I suspect what you have is a P0216, which is injection pump timing failure; and it has sampled enough of the buggers to overflow the buffer.

That leads me to suspect the CKP. That is what controls the timing reference for the pump.

If you have a local autoparts store that promotes free use of their OBDII reader, I bet you will get a long string of P0216 codes.

StakeMan

I suspect I will find a 216 code too. My guess is the VP44 itself is failing. It only has 110,000 miles of abuse on it.

banshee

Stake,

Mine will miss a little when revving it up in neutral, too. I think it's just a combination of the boxes, injectors, and cam that cause it to stumble a little bit. It doesn't sound bad to me... just... rough (like a racetruck).

On the codes, I think the 1693, 1694, and 1698 that I'm getting are for the same reason you're getting one... the BD RAD box. Those codes are in line for what the computer would give when the torque management wire is cut (according to dodgeram website). I wouldn't worry about the stumble.

John

StakeMan

The BD box has not been on since the last time I checked codes.

There is more to it than a stumble and a code. The truck hasn't felt right for a while. Hard to explain but something isn't the same.

Agades

I had same problems
I wouldnt go buy a pump unless that 0216 code shows

check all and I mean all electrical connections before buying parts

I learned the $$$$ hard way $$$$$

I replaced everything and never cured the stumble :'(

a guy I know fixed a similar problem by cleaning battery posts and removing the main ground to the engine block (passenger side) and cleaning it thouroughly

not saying this is THE fix but a possibility

there are many causes of a stumble in these 24 valvers
some we are just learning

banshee

stake,

how about your pump wire connection and the ground to your box? I've seen that cause a stumble before, too....

KwikKurt

I agree! A bad ground for the fueling box will cause all kinds of problems..Codes, Stumbles etc.

777 MECHANIC

The TST PM3 comp. causes a miss when reving above 2000 RPM in neutral on my truck Turn the box off while still up in revs and the miss goes away. All grounds are good. All connections checked. Does not miss at idle. Does not miss while driving.
The bigger the injector, the worse the miss. So it is a combo of things. At least on my truck.

MikeD