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Car shuts off after 2-3s full throttle [2.4 jtdm]

4K views 27 replies 7 participants last post by  oliveiraz33 
#1 · (Edited)
Hi guys

Today on the Motorway, my Brera (2.4 jtdm 210hp) died at full throttle. I was overtaking a car, full throttle for 2 or 3 seconds and the engine stalls, it really stops to 0 rpm if I put in neutral. and I saw no error coming on the dashboard. Turn the car off and on again and it's working fine. Did a second time to recreate the throttle and the exact same things happens. So 2-3 seconds of full tilt and it shuts off.

It does have a light remap, and it smokes a little under full throttle, and no shut off or smoke at 90% throttle, only when 100% the smoke and satalling happens. Boost looks fine at just over 1.5 bar

Any idea what it can be? Can it be a boost leak?

Thanks in advance :)
 
#4 ·
When my last diesel (not 159) exhibited those exact same symptoms it turned out to be the high pressure pump failing internally.....might be worth checking the pressure with the computer.when you download the fault codes.
 
#5 ·
I had this on a 2.7 diesel merc ml and it was accompanied by an EPC (electronic power control) light on the dash. Turned out to be a faulty fuel rail pressure sensor thing.
 
#7 ·
So today, I did a small pull from 2500rpm arriving home, it got much worse, it died on me right away, almost instant. I said "screw it", I'm not waiting on the weekend, I'm pulling the MAP sensor right now since I still have some light left.

Tools in hand, took MAP out, it was full of Carbon build up, I cleaned it all the way with carb cleaner. The cam belt was done 20k miles ago so I don't think I want to clean the intake anytime soon :(

Took the car for a quick spin, did two pulls up to 4000rpm and it didn't died. Can't see how much smoke it did because it was night already. So I guess it's kidna fixed, but I'm going to wait a few more days.

Last week I used those sprays to clean the turbo and intercooler, I guess that thing got in the intake manifold that should be full of gunk, diluted the carbon and let it cover the MAP sensor, making it malfunction. Lets hope it was that.

I scaned the car with FiatMultiscan and there were no errors (???) wich is very weird.
 
#9 ·
I don't have DFP and EGR is bypassed since I bought it, but I guess previous owner never cleaned it. Trouble is that Cambelt was done not long ago and I have to take it off to get the damn manifold off for cleaning. Otherwise I would have done it way before
 
#19 ·
no he's saying that perhaps the map isn't brilliant so in some circumstances a certain combination of inputs from various sensors doesn't have any output/appropriate response from the ECU so there is no fueling causing your stalls/cutouts.
 
#20 ·
Oh ok.

The remap was made by the most reputable shop in in my city, and one of the most well known in the country.

So I would assume it was properly made, it was expensive.

This weekend will be extended, so I'll try to clean the intake, throttle body, and see how if the swirl valves are open.

Could a boost leak cause this? I don't hear any leaks form inside the car, but the bottom pipe is known to leak sometimes, and my boost goes fine to 1.5 bar.
 
#21 ·
I know I posted before but it still sounds like fuel pressure to me (faulty high pressure pump). If the pump cant deliver the correct pressure you may find it runs fine at low revs.....but when you accelerate hard the pump cant keep up with demand and rail pressure drops. The ECU will shut down the injectors below a preset pressure (7000 psi rings a bell ....but don't quote that!)....it does this to protect the engine. You need to use a code reader with live data and leave it connected whist driving to see what happens to rail pressure just before it cuts out.
 
#23 · (Edited)
I'll try that. Would those bluetooth OBD be enough to read fuel pressure?

I have MES but the connection with the PC doesn't seem stable enough to check it on the fly with the car running.

EDIT: Just got in my head that I must change the fuel filter. I bought the car 1 year ago and never changed the fuel filter. I wonder how long it has been on, and might be causing fuel starvation
 
#22 ·
I doubt a boost leak would do this. You'd feel underpowered and maybe some black smoke under hard acceleration but not an engine cut-out
 
#28 ·
I changed the fuel filter yesterday, in hopes that the previous owner didn't change it, and it was blocking the fuel flow. Gave 3 good pulls and it didn't stall at all.

I work a bit close from work, since I don't like to push the car until is at operating temperature, between that and the usual traffic is hard for me to give it a good full throttle blast. But i'll be giving a good pull whenever I have oportunity and see how it fares.

I've aso ordered a bluetooth OBD reader to have a "on the fly" diagnostic, since the laptop connection with FES isn't very stable with the car running.
 
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