Using my HawkEye Total i'm getting a P1190 Fuel pressure plausibility governor deviation versus engine speed to high DTC.

Symptoms are:

Engine takes longer to start around six to eight secs only when cold
A slight rough idle when warm
ECU lights the fault lamp when engine is under heavy load and then gives a reduced performance. Light goes out after engine restarts.
Surging at high engine load.

At idle looking through Hawkeye im seeing this:

High pressure Rail 28659.1 kPa
Manifold Pressure 101 kPa
Low Pressure Rail 357.6 kPa

When revved to 4000rpm:

High pressure Rail 64483.1 kPa
Manifold Preesure 129.6 kPa

Ive given the car a recent service, oil, filters and new LP pump and cleaned out inlet manifold.

what stands out is the MAP readings at high revs if im correct?
 
2 threads running with the same fault. That's unusual, and an unusual fault too.

Your live data looks ok to me.
 
So I've done a quick leak back test before i head to work by letting the LP run till time out . Injector 4 starts leaking back very quickly. 3 leaking back slower . 2 and 1 very very little. Perhaps I'm getting closer to the problem .
 
Hey, it's me who has the same issue. So interesting. I will also go back to injectors and repeat leak off test. Good luck!
 
In any case the way I see it, 1-2 of your injectors are leaking, so thats 90% the cause. I saw another post here with same 1190 code and the problem was injector leak (4).

Also, when you cleaned inlet manifold, did you clean MAP sensor too? Did you take it out? MAP should be checked under load. Should be close to 180+Kpa in higher gears.
 
So basically, from research, we are losing pressure somewhere. That's why we need to crank engine longer, to build pressure. It can be from the tank/LP pump, HP regulator or injectors. With injectors it's easy to test. If you have a multimeter you can test their resistance too. Should be consistent for all of them. I still need to check my regulator valve, cause it's hard to access. I've actually never touched one. Did you test yours?
 
Hello, I haven't checked or tested the regulator yet but I do have a spare on another pump that I may use if needs be . Pump was professionally refurbished four years ago by a diesel specialist.

Injector 3 and 4 were leaking back very fast as soon as I started the LP pump . (Not engine on) Esppicially no.4. it's like the piezo solenoid in the injector gets stuck and so the diesel just leaks back. When started is smooth untill warm then idle is slightly rough. I notice the ECU trying to equalise the idle. Hawkeye tells me that there is a imbalance in compression on no.3 and 4.

Next Weds I will attempt to change the two injectors . I'll go out for a drive and get some diesel and get the engine hot . Then come back and slowly undo the two bolts of the injector . Half a turn each whilst engine still running untill I see injector moving out and engine noise changing. Then switch of engine and take of inlet manifold and get the injector out .

Yep, cleaned the MAP sensor.
 
That’s great! Well you most likely found your issue. Your compression inbalance probably means explosion on top of pistons occurs before the spark, or simply just randomly, and that pushes the pistons against their will ... and hence the rattle.

My idle is rough in general, unless I disconnect the high pressure sensor, then automatically idle is becoming smooth.

Brilliant strategy to take injectors out. A bit dangerous if screws broken . Will you refurbish them yourself or just replace them with refurbished second hand ones?

If mine are faulty Im thinking to give them an ultrasonic wash first.
 
I have three spare injectors that I've refurbished, cleaned and checked sitting in the shed . So I'll use them.

Quickly, tonight I loosened injector no. 4 bolts a little and gave the engine and crank and started it. Thankfully injector no.4 has lifted up and smoke appeared and so I have broke the carbon seal . I then sprayed carb cleaner down around the injector and then undid the injector bolts a little more and started car. Injector moved again . Clamp hard up against bolt . So I know we have some movement so hopefully next week the injector will come out ok . Fingers crossed.
 
Interesting! Is there a way to avoid breaking the seal you think? Would you do it differently next time?
 
Getting a P0202 and P0204 fault now . I moved the injector harness out of the way earlier . Oops.

Car taking longer to start .
 
Hmm, on the other hand, my injectors are fine, they leak exactly the same, and very little. Here's what I got in 3.5+ minutes with few sharp acceleration too. I measured them each after. less than 5% fluctuation. So now I'm lost....At least you know your fault :))
 

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There doesn't sound like anything is wrong with is to me. It starts in the same time as most TD4s, and the readings look about correct too.
Are you sure you didn't get a dose of bad diesel at the last fill up?
 
I thought so too. This start was actually one of the best and engine was hot, which always helps. But normally takes longer. However this is just a stationary test. Fault comes after a few miles after start, usually after I downshift from third to second and release the clutch. I will try to get live data for when fault occurs. I wonder what other streams I should add/remove for this test. I can only film a limited amount of live measurements.

I saw MAP decreased at idle from 102.2 Kpa to aprox 100 after cleaning boost sensor.

Bad fuel? Could be! Yet I assume the fault code is generated because of a mechanical/electrical problem. If it was caused by bad fuel or not, no idea. Either way, I would love to know what that bad batch of fuel triggered.....

I believe I had some 1/4 Tesco fuel with diesel rhino when fault occurred. I then added premium BP Ultimate and problem disappeared for 1-2 days.... I think.... I just remember the car was blasting after adding premium... I was very pleased with throttle response. I can't remember exactly if I added the premium before or after the fault. Maybe I added the BP to the mix before the fault, but can't be sure. Damn, this is very useful info I forgot.

Since the fault I added 35+ litres of BP ultimate and no more additives. I haven't used more than 1/2 tank since. Drove it just for testing. I need to identify issue first, I can't risk damaging engine even more ...there is smoke coming out.
 
Managed to do the two injectors this afternoon. Only took me 1 hour to do . Got the engine hot and the injectors came out very nicely. Just popped out with a tug of my hand. Had a quick observation of the tips and both seemed covered in carbon . New injectors installed with copper grease and then did another leak back test. Much better with hardly any diesel leaking back when LP left on untill it times out. Car starts up in two secs now and not the 10+ seconds previously. Very little rough idle still but from that I remember the idle is meant to be up and down whithin a percentage . Test drive done . Car drives good and no surging. Perhaps a very little amount down on power . I guess the surging caused the increase in power as the ECU tries to compenstate at the time .

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Good stuff!! Well done! I suspect the P1090 is gone for good :).
On TD4 you can add any random TD4 injector without programming right?
 

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