I've got a 92 Dakota LE (5.2 v8, 4wd), that is having drivability issues. Up until this morning it would start to stumble - almost shut down - after it had been driven for a while, or built heat into it. This morning it was acting up from the start (cold day in NY). Here's what I know...First thing I did was check the fuel pump...it's got good pressure 39 to 41 psi and follows engine load and speed...goes up without a signal. Pressure holds strong after I shut it off...even goes up a little (1-2 psi). I will say the gas gauge has a bad spot in the sending unit for the gauge...just after 1/2 full it goes nuts, fuel light doesn't follow, and comes on when the tank is actually low. When I would get the codes (when I'd get any)...usually 12, 54, 55...or it was actually cutting out during a code check. I'd get things like 3's and got a 53, so I thought it was a bad PCM. So with that I swapped in a PCM (cleaned up terminals and thru in dielectric grease) from my 93 that I parted out and it started and ran ok, but didn't help the long trip issues. Checked the infamous splice and that was solid and clean. I checked a few days ago and got no codes. Checked this morning after it acted up and got the three above...and I hadn't unhooked or disconnected the battery. Thought it might be the temp sensor the PCM reads, the one on the gauge as always read low...like just above cold. Now I'm wondering if the ASD is bad or wiring to the PCM and it's losing signals to it. How else would code 12 show up unless the power was lost to PCM. So to summarize, short 20-30 minute trips are ok, any longer under high speed load or sitting idle for too long and it starts to skip, idle erratic, and sometimes stall, and misfire bad. When it does stall...starts right back up (so don't think it's the pump). Plugs, wires, cap and rotor are fresh. It does have an exhaust leak upstream of the O2 sensor...but that's been there for a while and never had this issue. Wonder if it's got a bad temp sensor that takes a while to get to temp, lets the PCM go close loop and then reads lean from the O2 and is causing this issue. I've recently purchased a DRB II tool and Powertrain books for this...and have the service manual from the 93. So have those tools at my disposal. It's just been so intermittent that it's hard to nail down. Looks like I have to crack them open and get going! Any ideas would be very helpful.

 

The code 12 will show up for 50 starts or so after the battery has been disconnected. The code list I read said that 12 means the battery had been disconnected within the last 50 starts. Read teh FAQ page it has a lot of stuff you may not think of on it.
Code 54 comes up "No camshaft signal detected during engine cranking"
That signal is from a plate with a wire lead coming off it that screws down under the rotor. IDK how to check it. Its called the Cam sensor, or switch plate and maybe a couple other things. The Cam signal will tell the injectors when to fire so it makes sense that this code fits your description of symptoms.
Code 55 means end of codes.

That is a lot of stuff you talk about I would start to diagnose by trying to solve the code that came up. If that doesn't solve the issue I'm sure other guys can help you diagnose further.

 

Thanks onemore94dak for the feedback. The funny thing was the battery hadn't been disconnect during the 50 starts. About a week before this showed up the PCM had no codes stored, just the 55 indicating 'the end', so might be the wire feeding power to the PCM is angry. Will have to dig into the distributor and see what the Sync. pickup looks like...last time I checked it looked ok...but that doesn't mean much. Anybody ever have and issue with oil spilling up past the shaft seal and shorting out the Sync. pick-up? Seems to only happen when it's been running for a while.

 

Well, yes, it has ... but that doesn't mean that YOU disconnected it.

Bad battery cable.

Bad battery.

Corrosion on the block where the ground attaches.

Corrosion where the positive cable connects.

IOW - A code 12 when nobody's touched the battery clues that you should be checking ALL the cables, ALL ends, that connect to the battery.

Because you've got a bad connection somewhere; and until you fix that, you can chase haints from now until doomsday and never find them all *grins*

RwP