P1210 fuel pressure regulator fault

[darbuck]

I am only probing cable that is disconnected on both ends to check for open circuit. It Ran 3 or 4 times as you can imagine it's not a pleasure to be around at the moment. I will inspect and clean all connections and test coolant sensor through temperature range in a bowl of water but I am going to pull all my ECUs again and clean connections test fuses and refit them carefully I would like to know if someone could post up pics of the earth points in the engine bay if they have them.
Edit
I can't scope it live as the car won't run long enough so I will have to test it using resistance the hotter it gets the lower the resistance not perfect but should show an issue.

[darbuck]

I found a video by scanner danner on circuit integrity testing so I am going to watch it and use it to test I think and then do the coolant sensor. I just want to make sure I am optimizing my time on this.the weather has turned aswell so going to have to leave it tonight it's getting dark anyway and my eyes make the world blurry at the best of times.

[Rhothgar]

I can't scope it live as the car won't run long enough so I will have to test it using resistance the hotter it gets the lower the resistance not perfect but should show an issue.

I know. I was just trying to think of how you could test it without having to lose all your coolant. Hopefully it's just water at the minute anyway.

[darbuck]

I'll drain coolant and lose a small amount won't lose much I don't think. a bowl of hot water and the sensor connected to an ohm meter to get measurements. There should be a rule of thumb on these I will have to look for it.

[Rhothgar]

I just watched a CI Testing video now by SD and looks a useful test.

I also found this on his forum. This is why I am hesitant about power probes. I couldn't trust myself.

"Power Probes can be very useful but use with extreme care it is very easy to overload the circuit by applying a ground you are testing and burn out the engine ECU or a module. When using dummy load to test the power supply to a circuit it has have a resistance in the same ballpark as the working load.

Also be aware the voltage displays on Powerprobes are far from ideal as voltmeters and won't give useful results on some circuits. The shunt resistance of the Powerprobe IV is 350K Ohms that sounds a lot but puts a load on the circuit you are measuring is enough load to pull down the voltage reading on electronic circuits. Measuring voltage with typical digital multi-meter will not pull down the voltage to any degree because the shunt resistance of a digital multimeter is about 10M Ohms. So while a Power Prove IV is fine for checking power to screen wiper, or an ignition coil or trailer wiring but if you use it on an electronic circuit with a high impedance (high resistance) such as a wheel speed sensor you will pull the output down and will not get a useful reading."

[darbuck]

I will need to study a bit more I think , I wonder if the fact I am getting several issues do I have a bad ground somewhere, it seems plausible to have a bad ground causing an open circuit.in the regulator and the coolant temperature sensor.

[Rhothgar]

I will need to study a bit more I think , I wonder if the fact I am getting several issues do I have a bad ground somewhere, it seems plausible to have a bad ground causing an open circuit.in the regulator and the coolant temperature sensor.

It all seems to be earthed via the ECU so perhaps unlikely as you would surely be suffering more problems than you are but certainly worth a check of MC12 and MC12a in particular.

[darbuck]

I have had a look this morning the wiring all seems to be intact no open circuits that I can find. So that is the wiring ruled out apart from the ground strap to the negative pole on the battery. It is working but the cabling is very corroded and I know there is no Comms with the battery Comms unit. Could this cause it I don't know? possibly.

[darbuck]

The heavens have opened here so I don't know whether I will get back out today. The weather is just not giving me a break.

[darbuck]

I have taken a few pictures of the questionable cable as you can see it is badly frayed. EDIT I am also wondering what the small rectangular unit is. The fuse board has a relay with a chunk out of the top of it would this affect anything I can't remove it to test it as it is a sealed unit. I don't know whether it was me who damaged it or not. I also got a picture of something a bit different.

[myglaren]

? Dragonflies ate my car ?

[darbuck]

he was having a nap I think he was lucky the dog wanted to eat him.

[Rhothgar]

Damn! My earlier post didn’t post.

My mate said that it is most likely an earthing fault at the ECU or somewhere between.

[darbuck]

That's what I am thinking myself at this stage, the exhaust temperature sensor is high voltage possible cause bad earth. The regulator is showing open also a symptom of bad earth. Coolant temperature sensor reading negative but when I tested it it was good through the range. I think I can rule everything else out. I am convinced it's a bad earth I found a used good negative battery cable on fleabay for 20 EUR so when it arrives I will throw it in. For the sake of a score it's worth it. I can only assume that the only thing else it can be is either a bad earth or bad computer earth internally but because it is graphing and trying to control tells me it's an external earth to the module. It was the computer I think I would have more problems.

[Rhothgar]

Fingers crossed then.

Have you thoroughly checked the ground wire from your FPR?

I’ve been scoping my MAP sensor today.

Scoped Pin 71 (MAP sensor signal wire at ECU) and Pin 3 (MAP sensor signal wire at MAP sensor) using 2 channels. They overlaid perfectly once I had back probed it properly.

I failed to do that at first and was getting variable results.

First picture is with bad back probing.

Second picture (I’ll need to upload when I am back up at my mate’s next week if I remember as I forgot to take a photo but I saved the data trace) has both channels overlaid and signal is identical. Red or blue trace appears depending on which channel I turned off.

A fun day.

Also did the top engine mount. It’s transformed the driveability.

Now left to trace what is causing the turbo pressure differential. Probably a knackered turbo.

It’s out of balance and therefore slow to spin up or not spinning up 100%