Hi, have you met Lilith?

Is this something as simple as swapping the fuel rail and pump to another MZR and seeing if the issue moves?

 

Are there any connectors that are identical to the one on the rail sensor that might have been accidentally swapped when you were fuckin around with wiring?

 

He's got like 4 pumps and rails on hand, he's basically already done this.

Edit: 4 rails and pumps that *I've actually, personally seen*

 

I'm going to do this tonight.

Also, one of my staff broke my fuel pressure gauge Friday while I was off work. So I have to wait for Snapon to get here Wednesday to replace it. So to confirm again fuel pressure is good and it is electrical not mechanical.

 

The only two connectors that are the same that I can think of is the relay next to the HPFP and the temp sensor on the water manifold. But those are hard to mix up and water temp wouldn't read and wouldn't affect fueling.

 

I doubt your ITFP is messed up. No way is it going to run at 0 psi with that not feeding properly, and no way in hell is the fuel system going to be able to handle 900 PSI coming from the ITFP.

Lol.

 

Realistically the entire fuel system is brand new minus the sending unit and rail itself.

I'm talking to my guy right now about reprogramming the other ECU and cluster. Might be able to get this done this week.

 

Data systems need only three things to communicate. Power, ground, and serial data.

Now what can get wonky is in two wire networks the need for twisted wires. Have you done anything anywhere that could have separated a twisted pair of wires for data communication?

For example I had to rewire a car at work where there was bad wiring between a module at the front of the vehicle and one at the rear. I ran the wires but didn't have them twisted together. Then I realized my mistake and twisted the wires and then the communication came back.

It could also just be bad wiring. Even if it ohms out good, shows good voltage etc the wiring can still be bad. The data just breaks down during transport across the wire.

Just throwing suggestions and questions out there.

 

I completely understand all of that. I mean.. is it possible, sure, anything is.

Now this is something I have thought about many times over. Thinking about the twisted shielded pair that run to the CPS on this exact harness. The original harness, those wires had been damaged right above the alternator in the heat shield. Melted together infact. Is this one in the same boat... Not going to lie, it has kept me up at night. But the symptoms are now different.

With this harness I have not removed any loom, or tape, or clips from it. It was metered off the car and on the car, plugged into everything and nothing, also with and without power reading from the backside of the connectors.

Also a possibility. I just don't think it is.

I appreciate the input, good to have double checks.

At this point, I am open for anything and almost feel I need to start from scratch and pretend I haven't done anything.

My guy who can program the ECU won't be able to make it out till next week. So I have more time to troubleshoot.

I think starting at the beginning of the troubleshooting guide is a good idea, but at the same time I feel I'm just going to end up replacing the pedal, TB, FRPS, Crank and cam sensors, Map and MAF sensors and it's all going to lead me right back to the ECU.

 

It's highly unlikely you have multiple bad sensors. The common denominator is the ECU. Do any of those sensors share a common 5V reference?

GM vehicles will throw codes for 5V reference 1, 2, 3 and so on. What we do for those codes is disconnect each sensor one by one on that 5v reference line and monitor the 5V data parameter to see if it changes.

So if the TB, MAP, and CKP sensor was on one 5V reference, and let's say the MAP was shorted. You may see the 5v as reading 4.5V in the scan tool and once it's disconnected the data goes back up to 5V because part of the reference voltage was being shorted through a sensor.

Now if you disconnect every sensor on that 5V reference and then you're seeing less than 5V still, there is no Short to Ground or Short to Voltage then the only repair is to replace the module.

Since you're losing data while it's running can you scope the 5V reference lines on the faulty sensors? Or use a min/max function on a meter to try and catch it when it happens?

 

Honestly I am not sure on this. I will have to go back through the schematics on pro demand. I doubt the abs and fuel pressure sensor share anything outside of the ECU. But again, I'd have to research more to know for certain.

I have some other things the came up when I walked in the door that I need to take care of. I'll look more into this tonight or tomorrow and report back.

 

Old lady needs some dick?

 

Naa, I think our furnace just took a shit.

 

Well, furnace didn't quite take a complete shit. But damn close, the capacitor somehow back fed and blew the feed wire off, gotta call the HVAC in the morning to come out and take a look. Fortunately the outside temp isn't super cold and it's been getting nicer during the day.

Yay me for owning a home

 

Definitely worse than I expected, HVAC company came out, capacitor blew up, fried the board and now there's cracks in the combustion chamber.

Waiting on a full bid from the company. Will have to call a couple others to get more than one bid.

Fortunately we can go without for the immediate time being as the weather is in that sweat spot.

Talked to my buddy who's got the programmer. Since he's never worked on Mazdas he's afraid he might lock the ECU out. So I might just have to go to the dealer. Going to look into that tomorrow.

In the meantime, I'm due for some light reading for more research.