Right, this is my mates car not mine.
Running a FMIC and stage 2 map
Items replaced;
Recon R70 with brand new FPR
Low milage 076 injectors with low leakoff measurement on PP
Replaced FRPS
Replaced engine loom
New relay behind ecu
Lift pump fully cleaned, tank partially cleaned (was disgusting)
New cam and crank sensor from pug
Alex came up with peugeot plannet the other week (before most items were changed/replaced but still a new FPR) and read up the codes, main issue was the fpr was jamming then the rail pressure rising causing it to cut out.
Swapped out the FPR to another then it was fine for 40ish miles (like normal after a fpr change)
Went over yesterday, Original map installed, same issue until a new FPR was installed, and was fine up and down the road (2 miles),
Full s2 with high rail pressure installed, cut out under load.
Cut back pressure map installed, drove 20 miles to drop me home was fine until it cut out coming off the throttle, now back to the original problem of cutting out on idle.
Only thing I can see is it being a ECU issue, or the car engine bay loom.
Anyone else got any ideas as to why this could be happening?
Or a 162 ecu we could borrow to try? (free s1 remap or a copy of the s2's for future use? if you want them)
I can come up again, see what else we can find, i've got a couple of ideas. Is he using a genuine fuel filter?
Hp pump? Have heard of that being the cause on a few cars running stage 2 before with cutting out under wot
Cheers alex, I'll get james to text you if he wants you to come over again.
Can you reprogram imobalisors?
Dan, got a recon pump on it already, uprated too.
100‰ the refurb was done properly?
If you could come up again alex that would be great mate, its same as before me and chris changed the fpr putting the new one I took off when u was around back and it ran fine for 20 odd miles! I'm tempted to ring up the bosch place and moan about this pump however it could be a range of things
Not 100% with the refurb but it was the same issue before the pump was replaced.
Either way I've a brand new one on route and a used one too that could be tried.
Can't do immob stuff on this yet Chris, wouldn't know where to start.
Not a problem Jaymes, that's a real shitter. It's this idle problem that's got me stuck, really odd.
Jus read through and relised chris's post isn't quite right, never did this idle cut out thing before I changed the pump and injectors, just used to cut out under harsh load where I believe the injectors were losing pressure as they were f*cked! We changed the diesel and filter today, also the brown relay behind ecu and no change
That is an odd combo of faults to be having.
Did you log RP and RP valve duty cycle?
Who made the map, have they checked for bugs or anything funny against the logged numbers (ie, tried making a map to force the error or to force it to go away?)
Cheers
Dave
No logging was done, but should be able to when Alex comes over again.
It has the same issue regardless of the map, OE, SP Tuning S1, or the S2 (not saying who's map as it wasn't bought direct from the mapper but runs fine on there car)
Just a quick Q... You say it's cutting out under harsh load, how much fuel is in the car? I've heard before of someone where they had around 1/4 tank in the car and under full throttle it would cut out, the fuel would hit the back of the tank under acceleration and then clonk out because it couldn't get any, just a thought!
If not, my betting would be on the pump
It used to cut out under load. It cuts out now on idel or coming off the throtal.
If you have PP you want to watch the idle rail request and actual, and also the duty cycle of the RP valve.
If they are all normal then I'm stumped why it'd cut out. Hmmmm...
Dave
When it cuts does the EML stay on for the next few starts? When you get the low request vs actual as I remember the eml stays on until there's been 5 successful start and runs....
Can you get railpressure from the obd port, or only through pp? Stick a volt meter on the RPS output and monitor it there...
You can log RPS with a multimeter. Mine will do logging via rs232 to a laptop, then you can combine all your CSV database stuff into one big log and plot it later.
Ooor, you can do rail pressure via PP, along with oodles of other very useful data.
Usually that is all overkill though, PP is good enough to spot failings if there are any straight off if you have one person driving and you watching what is going on in my experience.
After all that, good old swapping known good stuff for possibly bad stuff is a good way to find your problem.
Ie, tank pump might be on it's way out.
Dave
When running on pp the rail pressure ramps up then cuuts out at double the requested value. This is when sitting at idel.
Also the only code logged on pp is that the fpr is jamming, but it does it regardless of the regulator fitted ( although it'll run fine without logging a code for a while after its been changed)
Also a new ecu has been tested with a original map on and the issue is still there.
Deffo gonna be hardware related then.
Odd.
Maybe one of the injectors is faulty and working against the FPR... the pump is just a pump really, and can't do anything about rail pressure in itself, it just spins and pumps hehe... the FPR is what does all the work really.
So unless the pump is pumping TOO much for the FPR to cope with, but I find that hard to believe.
Ooooor, the rail sensor is dicky and is reading too high.
Does the FPR duty cycle % sit too high generally vs a standard car... that will be what gives you an indication of some things.
It's kinda good that it's hardware though, makes life easier. It's just a case of being methodical and looking at the PP readouts to try work out what bit of hardware is causing issues I guess...
Does it idle ok when it is running? Ie, all the injectors are working and it's running smoothly. If they are all working then the only things left are pump/FPR, and since the pump is pretty inert in all this (engine speed is only input really), then the FPR is logically still what isn't right...
That said, it might ALL be working ok, and the rail sensor might just be telling the engine lies...
Hmmmm, hehe, tough one but interesting to work it out
Dave
Wait, so the actual pressure is higher than the requested pressure, you said so.etching about the rail pressure being double... Sounds fishy?
Sounds increasingly like the ecu getting funky signals from the FRPS, is the FPR actually wide open, still just enough flow for the engine to run with, but the sensor saying the pressure is mental... IMHO check the voltage from the sensor, make sure it makes sense vs requested... Just because the ecu is receiving one value and spitting it out to PP, doesn't mean its correct, its another thing you can then discount....
hmm
Ruan, the pressure sits fine, then suddenly will increce which then causes the cutting out. After it cuts out it logs a code saying the fpr is jamming.
When running it runs perfectly, good power untill it cuts out, as said this is only when letting off/sat at idel.
The rail sensor has been changed, but to one that isn't tested.
question might be related or might not be!!
FPS on the injector fuel rail, on some s2 maps dont people use differnt fps and have to change wires?
when they run a different higer pressure fps
im sure this is for the hotter maps and not the s1 or std
maybe the map you have has a request for the higher/lower pressure sensor
We were seeing over 600 bar at idle just before it cut out, i can only see two options myself - FPR or FRPS. Doesn't matter how knackered an injector is, i really can't see it ramping up the pressure that much, although if i'm wrong i'm open to being corrected.
As far as i'm aware Cully, the two pressure sensors aren't a direct swap, a map to suit that DV6 FRPS wouldn't run with a standard sensor and vis a versa. Besides, it's generally only used for those that go beyond s2.
I agree, the pressure sensor and relief valve are the likely obvious culprits... it's very unlikely to be anything else I think.
You can watch both 'ECU' values on PP so I'd just watch them while it fails.
Or better still get a decent multi-meter and log the actual voltage from the pressure sensor, log a failure event.
Then do the same on the duty cycle from the relief valve.
It is a weird one because if the RP drops it'll make the valve close up to increase RP, but if the sensor is reading low any way, then how does it know to cut out?
So it might be a half second or second where it reads low, then returns to normal to see the RP has risen massively, and so cuts the injections.
If you log the actual sensor and then the sensor feed at the ECU multi-plug (possibly at the same time), then you could assure the ECU is seeing the same signal as the sensor is seeing, and look for any odd readings around failure (ie, a dip before a sudden rise)
Hmmm
Dave
Well it occured to me earlier whilst day dreaming that this whole thing began god knows how long ago when i fryed my lift pump with a live wire. It also managed to fry the stereo and clocks at same time so im wondering if my problems there? as i never had an issue with it before that day?!?
also the fpr ive got in there atm seems to be working ok, Its got no pin on the end of it though, it runs normally with random spikes in the revs at idle now and again but cuts out when you give it the slightest shit on the throttle?
Dave, the duty cycle looked fine from memory, but i'm going to do some logging from my own car so i've got something solid to compare against, never have liked relying on my memory lol. Also, the rail pressure rose steadily from ignition until it cut out when the old FPR was in there, thing was definitely completely jammed.
Now that just sounds like a knackered FPR again. Did you ever change that lift pump? If so, i guess we should hope Cully's got some bright ideas on what's happened to your electricals...
Tank pump would be an oddity to push RP up so much from idle though.
I'm stumped at this point.
All you can really do is just methodically go through every function and check it gives normal results like you plan to do.
Not sure I like the idea of fried bits of loom haha... this is where logging the sensor reading and the reading at the ECU plug might show that the signal isn't arriving at the ECU as it did when it left the sensor... ie, the sensor is reading right but the ECU is reacting to a loom ghost issue basically.
Hmmm
Dave
Well, this all seems to have gone away, Put it down to a shit halfords fuel filter letting crap through to the fpr
Wwwwwinnnarrr!
Mine's still running fine too, so bizarre....
Halfords fuel filter haha...
Just goes to show that it's often the simple stuff and we can over-complicate matters.
It'd be interesting to get a new OEM and new Halfords filter and run them side by side to see if the Halfords one really is causing issues.
Or if it was just the housing fitment wasn't perfect and disturbing it has rectified an issue or something...
Hmmmm...
Glad it's sorted
Dave
Interesting read.. what fuel filter did you use... I seem to have similar issues, fine until under heavy load