So I finished rebuilding my truck the other day. Started right up and took it out a few times, ran and drove great. The last time however, I took a corner and accelerated and my gauges went nuts. The water in fuel, check engine, check gauges lights all came on and my oil pressure gauge also reads 0. I have no idea what's going on or why that happened? Ran the truck a little after the fact and it still runs and idles fine without any excessive noise so I don't think it really has no oil pressure. Any insight would be appreciated. Thanks!

what was rebuilt?

The engine

Test your oil pressure at the oil filter base.Then pull your error codes to give us clues of what is going wrong.

Sounds like a loose connection to me, check all the connections on the PCM/ECM and along that harness to start.

I am thinking loose connection or ground as well.

It also has a new ECM, well it's just out of a different truck, but new to mine. Didn't have it flashed but it worked right when I plugged it in, don't know if for some reason after a couple days of driving it this could be affecting it or not? I'll check for loose connections tomorrow though, seems kind of odd for something to actually be wrong

It also has a new ECM, well it's just out of a different truck, but new to mine. Didn't have it flashed but it worked right when I plugged it in, don't know if for some reason after a couple days of driving it this could be affecting it or not? I'll check for loose connections tomorrow though, seems kind of odd for something to actually be wrong

That explains a lot, unless the ECM came off the same year and same option pickup, it will cause the gauges to go funky, it is a good tell tale you didn't have the ECM flashed to your rigs specs. Many folks have ran into this exact problem with ECM swaps.

That explains a lot, unless the ECM came off the same year and same option pickup, it will cause the gauges to go funky, it is a good tell tale you didn't have the ECM flashed to your rigs specs. Many folks have ran into this exact problem with ECM swaps.

Even after it ran fine for a day or two and none of those lights/errors were on? Just thought it was weird that it wouldn't have happened right away and been wrong from the get go

That is weird, but is the ECM actually from the exact same model year and specs?

That is weird, but is the ECM actually from the exact same model year and specs?

The date of manufacture is really close, exact same part number. I'm not sure if it was an auto or manual. The guy I got it from just receives parts in bulk and supposedly checks them to make sure they work and whatnot but doesn't know the ins and outs of the vehicle they come out of.

I would check connections again and then pay a dealer an hour labor to have it flashed just to be sure. It will save a lot of time and headache in the troubleshooting scheme and then you can rule it out for sure.

Ok, So it seems that every time I dig into my truck to figure out the issue something else comes up.. I'm at a loss and have no idea where to go from here. The water in fuel light, check gages, check engine lights are all on. The oil pressure gauge sometimes works, and sometimes doesn't, radio cuts in and out. The tach also will come and go as it pleases. Now I am also having trouble with the truck starting. Some days it fires right up, and others it will crank til the batteries are dead. If I leave it sit for a day or two it won't start when I try. Idk if it's the ECM, the gauge cluster itself, wiring, a sensor, multiple sensors? The truck runs PERFECT, nothing was wrong when I pulled the motor, had it rebuilt, stuck it back in, plugged everything back in, and now issue after issue.. Any help? Thanks

Idk if it's the ECM, the gauge cluster itself, wiring, a sensor, multiple sensors? The truck runs PERFECT, nothing was wrong when I pulled the motor, had it rebuilt, stuck it back in, plugged everything back in, and now issue after issue.. Any help? Thanks

Until you rule out the ECM by re-flashing it to the correct parameters it will be hard to go any farther with your issues, Your issues are classic symptoms of others who have done the same swap and put on a different ECM.

Until you rule out the ECM by re-flashing it to the correct parameters it will be hard to go any farther with your issues, Your issues are classic symptoms of others who have done the same swap and put on a different ECM.

Yeah, I actually had an appointment to get it to a guy that does that this last weekend but didn't want to bring it down there and have it be dead in his way because it won't start from day to day. Wanted to get that squared away before I cruised down there. Makes sense though, I'll try to get it there. Thanks

Does he have a factory DRB computer with capability to do this sort of re-flash? Never heard of any private individual having the access to this tooling or factory files / usually a dealer only type of info. The only other places that I thought did this are ECM repair companies or Bob Wagner from Smarty can have this done.I am very interested in this if there are other sources who can do this.

Does he have a factory DRB computer with capability to do this sort of re-flash? Never heard of any private individual having the access to this tooling or factory files / usually a dealer only type of info. The only other places that I thought did this are ECM repair companies or Bob Wagner from Smarty can have this done. I am very interested in this if there are other sources who can do this.

To be completely honest I'm not very familiar with the any type of electrical work, wiring, checking for codes, or computer related problems. I just know a guy that used to work at a chrysler dealership and has a scan tool and said that some of the older models just had a vin on the ECM and if you punch in the vin on the new ECM it will sync to the truck it is now in. He said I may have to end up bringing it in but being that he could check it for no charge first I figured it was worth a shot

Ok so now my main concern is the issue with it not starting. I atleast want to be able to start it and move it around before I bring it somewhere to have the ECM flashed. The batteries will barely crank the truck over, sometimes it starts and others it will crank for a short period until they are dead. If I check them they read 12.8 or higher every time but still barely crank the truck.. Does this mean the batteries are junk? Just seems weird that they read good on a tester

Check the connections. Time to clean ALL battery connections and see what happens.

Check the connections. Time to clean ALL battery connections and see what happens.

I've cleaned, and checked all connections to make sure they're tight. Everything was good

I went and got new batteries, my old ones were junk. All was good for a while but now my lift pump isn't running, at all. You can bump the key and I don't get a cycle, and if you try and start it, it will just crank. I'm not sure if it would just be the relay, the ECM, or the lift pump itself? Any of those things a common problem? Thanks