CDI trauma - won't start
So, I started with what a weird accelerator pedal issue (that still needs solving), and now I have an engine that won’t run. The only relevant codes have to do with the accelerator pedal (1222-8 and 1234-8, pedal sensor 1 & 2 failure). There was a camshaft error stored but it’s not current and I replaced it to make sure. When cranking, I can watch the real time values of the fuel rail and I’m seeing up to 450 bars (6000 psi) but don’t know if that’s enough. I cracked the fuel lines going to the injectors and there is fuel leaking out.
So for the moment, I’m feeling like I need to forget about the accelerator and just focus on getting the engine to run. I need someone to guide me through the fundamentals for getting it to run again. Here’s the bottom line status:
1) Cranks over, won’t start and run. Comes close enough to where the starter disengages.
2) Fuel rail pressure 450 bar (6000 psi) during cranking.
3) New Camshaft sensor.
4) ECM codes 1222-8 and 1234-8. Pedal sensor 1 & 2 failure
5) ECM code 1611-2, supply voltage low, but I've probably run the battery down some cranking so much. It’s a new battery and I’ve recharged it.
Thanks for the help guys, this is getting old and it's come at a bad time for me personally.
Mark




I had PPS codes on older models and not only they would not prevent engine start, but the car was drivable in default mode, what was about 50% of power.
Maybe for new models bad PPS will stop the engine from running, maybe not, but since those are the only codes (?) you have, you don't have much choice than get new PPS, don't you?
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@Michah - the only reason the rail pressure falls is because the engine attempts to run and when that happens, the starter drops out automatically and then the engine quits. So you get this cycle of cranking (high pressure) followed by almost starting to the point of where the ECU thinks its going to run and drops the starter out. Since the engine doesn't stay running, pressure drops to nothing. As long as its cranking, pressure seems to be there.
On the CAM, I replaced it with a new one and it made no difference. I should have known better.... I don't think the CAM will prevent it from starting.
Last edited by M D; Jan 11, 2019 at 09:01 AM.
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My car 06’ CDI idles at about 5-5,500 psi rail pressure warmed up, peak rail presssure under full load is 23,650 psi with my mapping. Check for rat/mouse chews on wiring, especially to Cam position sensor. It sounds like the fuel pressure regulator is working on back of fuel rail. Can you data log and screen shot say 10-15 seconds of cranking, showing rpm, fuel pressure rail, fuel pressure pump and say MAF?
My car 06’ CDI idles at about 5-5,500 psi rail pressure warmed up, peak rail presssure under full load is 23,650 psi with my mapping. Check for rat/mouse chews on wiring, especially to Cam position sensor. It sounds like the fuel pressure regulator is working on back of fuel rail. Can you data log and screen shot say 10-15 seconds of cranking, showing rpm, fuel pressure rail, fuel pressure pump and say MAF?
One thing that has a question mark for me still is rather the fuel getting to the injectors is enough. I might have thought that if I loosened an injector line to where it was completely off, like I did, that 450 bars of pressure would have made the fuel spray out of that line like a high pressure washer - but it doesn't. It comes out but doesn't appear to be a high pressure. Of course, depending on how much volume the high pressure pump is designed to pump, opening a line to atmosphere like I did may not be a super high pressure stream. I can't physically measure the rail pressure (no gauge that high) but as mentioned earlier, the real time data shows the rail pressure to be in the 450 bar range while I'm cranking.
A648 150 42 79
CR3.43 3.2L
FD 05M11
HW 39.04
SW 34.05
Bosch - 281-013-219
23.11.05 1039S00000
59123b1894 0201
Last edited by M D; Jan 21, 2019 at 06:21 AM.
So someone might think that the ECM is bad but I just put a new one in it and its acting no different. So my question is why only 2.3 volts?? I assume it should be close to 12 volts. Is there some logic or condition that would cause the ECM to output low voltage for some reason or is there something I'm overlooking?
So someone might think that the ECM is bad but I just put a new one in it and its acting no different. So my question is why only 2.3 volts?? I assume it should be close to 12 volts. Is there some logic or condition that would cause the ECM to output low voltage for some reason or is there something I'm overlooking?




