Is this something as simple as swapping the fuel rail and pump to another MZR and seeing if the issue moves?
Hi, have you met Lilith?
- Thread starter Rokusek
- Start date
Is this something as simple as swapping the fuel rail and pump to another MZR and seeing if the issue moves?
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*
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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.
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.
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.
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?
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.
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
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.
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.
Had to take a serious mental break from this car. Summer came and is now on its way out. So things are slowing down a bit till rifle season opens next month.
Was able to get our furnace a band aid for now. shits too fucking expensive.
Still have not been able to get my buddy over here to reprogram the new ECM. I am considering buying one preprogrammed from Flagship1 which I feel I will regret. We shall see, still working this out.
My Corksport Coilovers finally showed up a while back. This winter will be a suspension upgrading adventure for sure.
Was able to get our furnace a band aid for now. shits too fucking expensive.
Still have not been able to get my buddy over here to reprogram the new ECM. I am considering buying one preprogrammed from Flagship1 which I feel I will regret. We shall see, still working this out.
My Corksport Coilovers finally showed up a while back. This winter will be a suspension upgrading adventure for sure.
If your doing suspension do the bushings too
I lied, I did update you all
Took some time to rethink and re evaluate everything, ordered more parts. Had to wait for some others.
In the process of all of this I pulled my inner left abdominal oblique muscle. Put me in the ER for a day and down and out for almost a week. Still in some form of recovery being as careful as I can. But that was almost 3 weeks ago now. So slowly back on the grind.
Before we get started, let's all be sure to get our clown suits on.
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Now that we are all ready, here is what I have come to find:
So, I had to figure out the fuel pressure issue. I did find the correct fuel pressure sensor after trying 3 others I had on hand and another I found through work and two more I ordered via other sources all to be wrong. I found this is the one via summit racing. This took me far too long to find, it is the correct part number but listed for a Alfa Romeo and a Fiat. It works for the speeds as well. This is... THE ONLY PART NUMBER that works for my car and I'm going to assume All speeds. All the others that have been recommended on the forum and all over the Internet do not work. This fixed the fuel pressure issue. Mazda only sells this as a complete replacement fuel rail with sensor and pressure relief valve. The reasoning is due to the fact that the threads can be Damaged when replacing the sensor "air quotes"
Here is a link to the exact part.
https://www.summitracing.com/parts/bch-0261545053
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So now the fuel rail pressure issue is fixed, the throttlw position issue is completely gone. The only thing now is rich at idle and some choppiness when running.
This is where the clown suit comes in real handy
I am at a point that the last thing is the injectors. Something I knew was a possibility in the beginnin, but refused to admit it. Considering this was a used motor I shut have just replaced them off the get go last fall.
I have four sets of injectors now and sent a set off to injector RX. Even with 2 day shipping both ways USPS LOST the injector on the way there and the way back. It took about a month for turn around thanks to USPS. But they just showed up yesterday morning.
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While waiting for the injectors I sourced some injector studs nuts and found these upgraded filters from injector rehab. Since injector RX use's OEM filters I wanted upgraded filters.
https://injector-rehab.com/product/bosch-metal-universal-filter-8mm/
A picture of a junk filter from a junk injector next to the new upgraded filter and one installed in the injector for proof they fit.
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While all this was happening I was able to get the fuel tank lock ring tool and ordered a new lock ring and gasket as well those finally showed up. To finally close up the tank.
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I picked up some subframes to be cleaned, primed painted and new bushings put in. As well as new bushings for the front and rear lower controls arm and whiteline rear end links. I am still waiting on the front LCA bushings to be in stock from Damond before those get installed.
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So far I have bushings for the rear lower control arms, and the forward bushings for the trailing arms. Trying to source bushings for the front subrame as well.
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All the while my front and rear sway bars showed up from corksport with the Lower tie bar. Still waiting on the coilovers to ship. Being told they are still waiting on the bodies to get in for assembly then ship out. I'm hoping to see them within... Dare I say two weeks.
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And picked up a bearing puller kit for the LCA's as well as some transmission work to come. View attachment 28439
Well, after some winter depression and lack of desire to deal with this car, I finally buckled down and got my shit together.
Found two more bad wires in the cabin from the TB to the ECU. Repaired and confirmed ECU failed.
Used this thread to figure out how to reprogram an ECU. It didn't go as well as if I had a new one but she's functioning. I'll go more into details on that on another thread.
So I currently have a base tune on right now from Ryan at EMS (Previously at at PD). Working the tune through right now. Drove the car to work today have now put about 45 miles on her. No major issues so far.
This weekends plans are to drop both sub frames and do all the suspension work.
More to come.
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Found two more bad wires in the cabin from the TB to the ECU. Repaired and confirmed ECU failed.
Used this thread to figure out how to reprogram an ECU. It didn't go as well as if I had a new one but she's functioning. I'll go more into details on that on another thread.
So I currently have a base tune on right now from Ryan at EMS (Previously at at PD). Working the tune through right now. Drove the car to work today have now put about 45 miles on her. No major issues so far.
This weekends plans are to drop both sub frames and do all the suspension work.
More to come.
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