mhuppertz

The Check Engine Light came on today, and stayed on. The Water light has been on for a year. Everything else seems to be working (air, cruise, etc.) so I don't think it is the CPS. I have no idea why a diesel would have a check engine light anyway!

Any ideas????

Mark

Hemi Cat

If the light is red, you might want to check your oil. I'm not sure of the inputs that turn that light on, but you probably have a sensor wire that fell off or broke. You could also try plugging in a scan tool to read the code to identify the source. I think auto zone does it for free.

mhuppertz

Could my factory oil pressure gauge be lying to me? It seems to be working as normal. Oil level is fine. It comed on when I hit the highway going home.
Is there a scan tool that will work on a 1st gen?

wannadiesel

Yeah, any scan tool that will work on a '93 Dodge will work on your truck. Take it to an AutoZone, they'll read the codes for free.

mhuppertz

Dave,
Looking at your sig block again, where did you get the high flow banjo's?

wannadiesel

Geno's Garage. They sell them for 24 valve trucks, but they are the same size as ours.

http://198.104.149.53/CoastalData/sh...ID=593&CATID=1

Get one solid and one tapped. You can use the tapped one for fuel pressure or just put a pipe plug in it so you don't lose the bleed. I've got a 1.5" 15 psi glycerin filled gauge threaded into mine since I had it laying around. It bounces from 3 to 7 psi at hot idle, revved up it gives a steady 6 psi.

mhuppertz

Does the PCM retain data? If the light isn't on when I test it will I get any hisorical data?

wannadiesel

Some codes are retained through a certain number of key cycles, others are wiped out when you shut off the truck.

mhuppertz

My computer is throwing a code 24, which is TPS voltage high or low. That's wierd because I have a standard that does not have a tps (that I know of).
Is my PCM getting Alzheimers?

wannadiesel

That is wierd. No factory cruise?

mhuppertz

It does have factory cruise, but it doesn't have the typical TPS that the automatic has. If there is a TPS, I don't see it......

wannadiesel

No, I was just trying to find a difference between my PCM and yours. Mine hasn't set code 24. I don't understand why yours would start throwing a code for a sensor it shouldn't even be looking for. Is that the only code?

mhuppertz

The exact code is:
1 2 4 1 5 5

The PCM may have been marginally damaged when the serpentine took out the crank trigger.

mhuppertz

More on the mystery. I notices the voltage needle riding low when the "check engine" light is on. Also, the cruise control is very weak when the light is on, and lets go frequently. Interestingly, the air stays on, so it's probably not the crank position sensor.
I'm thinking low voltage to the PCM, but I can't figure out why. Id doesn't happen all the time, or it would run the battery down.
I'm at a loss.
Oh, and there seems to be more interference in the radio than before, and it increases with engine speed. I think someone stole my Cummins and stuck in a pinging gasser!

wannadiesel

My FSM says the TPS code shouldn't show up on a manual trans truck. Maybe you should take it to AutoZone and let them scan it and see what comes up. Very wierd.