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HPFP or injectors, best way to tell?
- jleckenby
- Member
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- Joined: Fri Sep 02, 2016 12:54 pm
- Location: Leeds, UK
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HPFP or injectors, best way to tell?
Evening all,
Car has been idling a bit rough for a while. Wondering if anyone can help identify whether it’s HPFP or injectors.
- No check engine light and only interesting code is a historic misfire on cylinder 6
- It often has a long crank (3-5 seconds), and the idle is a little rough (usually 650-750)
- Sometimes it works up to revs on start, sometimes it starts 1.5k-2k and drops down
- If I hold throttle steady below 2k there’s always a slight wobble, higher is constant
- Warm startup is always good, no long cranks
- Doesn’t really seem any power reduction (though it’s been a few months so could be wrong)
- Changed spark plugs and coil on cylinder 6
- No petrol comes out of exhausts
- HPFP idles 695-730
- Very ocassionally the start is very rough and engine light comes on. Restarting car sorts the issue.
The length of time the car is left doesn’t seem to make the crank longer. Ive been away for a fortnight and it started straight away (though on high revs). If the injectors were leaking would the length of time make it worse?
Any help appreciated!
Car has been idling a bit rough for a while. Wondering if anyone can help identify whether it’s HPFP or injectors.
- No check engine light and only interesting code is a historic misfire on cylinder 6
- It often has a long crank (3-5 seconds), and the idle is a little rough (usually 650-750)
- Sometimes it works up to revs on start, sometimes it starts 1.5k-2k and drops down
- If I hold throttle steady below 2k there’s always a slight wobble, higher is constant
- Warm startup is always good, no long cranks
- Doesn’t really seem any power reduction (though it’s been a few months so could be wrong)
- Changed spark plugs and coil on cylinder 6
- No petrol comes out of exhausts
- HPFP idles 695-730
- Very ocassionally the start is very rough and engine light comes on. Restarting car sorts the issue.
The length of time the car is left doesn’t seem to make the crank longer. Ive been away for a fortnight and it started straight away (though on high revs). If the injectors were leaking would the length of time make it worse?
Any help appreciated!
Z4 35is, 438bhp
Cobb Stage 2 (Aggressive), VRSF Catless Downpipes, BMS DCI, NGK Iridium Spark Plugs, Eibach Springs
Cobb Stage 2 (Aggressive), VRSF Catless Downpipes, BMS DCI, NGK Iridium Spark Plugs, Eibach Springs
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- Lifer
- Posts: 7020
- Joined: Fri Jun 29, 2012 7:53 am
- Location: High Peak,Derbyshire.
HPFP or injectors, best way to tell?
No,
If the injector drips then it will drop fuel pressure in the fuel system, the fuel pressure sensor will detect the low pressure and the car will be held in "non start" until correct pressure is maintained.
Hence elongated cranking times
Sounds like you have no6 injector at fault
If the injector drips then it will drop fuel pressure in the fuel system, the fuel pressure sensor will detect the low pressure and the car will be held in "non start" until correct pressure is maintained.
Hence elongated cranking times
Sounds like you have no6 injector at fault
- jleckenby
- Member
- Posts: 78
- Joined: Fri Sep 02, 2016 12:54 pm
- Location: Leeds, UK
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HPFP or injectors, best way to tell?
Hmm, interesting! I expected a long crank after leaving it for so long and there was no fuel thrown out the exhaust, hence wondering. Think I’ll take the injector out tomorrow and have a look at it!
Z4 35is, 438bhp
Cobb Stage 2 (Aggressive), VRSF Catless Downpipes, BMS DCI, NGK Iridium Spark Plugs, Eibach Springs
Cobb Stage 2 (Aggressive), VRSF Catless Downpipes, BMS DCI, NGK Iridium Spark Plugs, Eibach Springs
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- Senior Member
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- Joined: Fri May 26, 2017 3:40 pm
- Location: Plymouth
HPFP or injectors, best way to tell?
I would expect a strong smell of unburnt fuel if this were the case.Z4M-2006 wrote: ↑Thu Dec 28, 2017 9:18 am No,
If the injector drips then it will drop fuel pressure in the fuel system, the fuel pressure sensor will detect the low pressure and the car will be held in "non start" until correct pressure is maintained.
Hence elongated cranking times
Sounds like you have no6 injector at fault
Mark
Plymouth
E89
35i
Carmine Red
Black leather
Plymouth
E89
35i
Carmine Red
Black leather
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- Member
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HPFP or injectors, best way to tell?
I had long crank, strong smell of fuel and irregular tick over .
- ph001
- Lifer
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- Location: N. Yorkshire.
HPFP or injectors, best way to tell?
All those symptoms point to injectors from previous history. The long crank is usually as a result of loss of compression in one or more cylinders due to bore wash from the unburnt fuel on the piston rings.
- dario
- Senior Member
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HPFP or injectors, best way to tell?
If its like this.....
Then its likely the injectors.
regards
Glad i had extended warranty!
Then its likely the injectors.
regards
Glad i had extended warranty!
- jimbo1958
- Lifer
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- Joined: Wed Jun 09, 2010 10:49 pm
- Location: Romancing Your Mum
HPFP or injectors, best way to tell?
Ditto......3 grands worth of work for the injectors and module when mine went. Thank f*ck for the Warranty.
Z4 e85 3.0 - GONE
Z4 e89 35i - GONE
Jaguar F Type V6s Roadster
Abarth 695 Rivale
Z4 e89 35i - GONE
Jaguar F Type V6s Roadster
Abarth 695 Rivale
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- Member
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HPFP or injectors, best way to tell?
What year and what mileage were these cars that had the problems with the injectors and the hpfp, I think it was a noted problem on the early 35 models, just hoping it was all sorted by the 2015 model.
- dario
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HPFP or injectors, best way to tell?
HillWalker wrote: ↑Sun Dec 31, 2017 2:59 pmWhat year and what mileage were these cars that had the problems with the injectors and the hpfp, I think it was a noted problem on the early 35 models, just hoping it was all sorted by the 2015 model.
2011 /25k miles