Miss-fire help pleeeaaassseee......
#1
I am at my wits end, please if anyone can help, my car has been off the road for nearly 3 months now...
Simply a miss-fire, in every gear, like hitting a brick wall, coming on at about 3500rpm, really juddering and holding back, happens at any throttle opening past about 20%, will clear a little if you let off the gas. Clears totally at about 5000rpm if you dare to keep going...
Car is a MY96 UK turbo (hence my name!), with K&N induction kit and de-cat exhaust. I also have ApexiAFC, but all flat lining for now. Playing with AFC doesn't really make any difference. I have also just (last night) fitted plugs, leads and Bosch coils, as I was convinced they would cure this, no difference at all...
Please, if anyone has any suggestions I would be so gratefull, I am fast running out of money and patience, I just want to enjoy my car!
Cheers, Rich.
Simply a miss-fire, in every gear, like hitting a brick wall, coming on at about 3500rpm, really juddering and holding back, happens at any throttle opening past about 20%, will clear a little if you let off the gas. Clears totally at about 5000rpm if you dare to keep going...
Car is a MY96 UK turbo (hence my name!), with K&N induction kit and de-cat exhaust. I also have ApexiAFC, but all flat lining for now. Playing with AFC doesn't really make any difference. I have also just (last night) fitted plugs, leads and Bosch coils, as I was convinced they would cure this, no difference at all...
Please, if anyone has any suggestions I would be so gratefull, I am fast running out of money and patience, I just want to enjoy my car!
Cheers, Rich.
#3
Good thought, but this is also replaced, I got a second hand ignitor unit and it came with the whole lot attached!
Might clean out the "new" one anyway, just in case...
Cheers.
Might clean out the "new" one anyway, just in case...
Cheers.
#5
Hi Dave!
Yes, about 0.9-1.0bar, that is why I don't think it is air related, ie losing boost/air leaks/ blocked pipes etc...
It isn't the fuel cut either, I have experienced that and this is more like.... ermm....
...I'll tell you what it is like, does anyone remember manual choke cars??! If you pulled the choke out to far the car would stutter and lose power... that is what I am getting.
Assuming the ignition is OK, surely it must be fuel related somehow?? Poss pressure/blockages...? But would that be so precise, as in same revs in every gear etc...?
If not fuel then maybe management, but no "check light" and manual code reads clear.
Any ideas...?
Cheers Rich.
PS: Oxygen sensor is new too.
Yes, about 0.9-1.0bar, that is why I don't think it is air related, ie losing boost/air leaks/ blocked pipes etc...
It isn't the fuel cut either, I have experienced that and this is more like.... ermm....
...I'll tell you what it is like, does anyone remember manual choke cars??! If you pulled the choke out to far the car would stutter and lose power... that is what I am getting.
Assuming the ignition is OK, surely it must be fuel related somehow?? Poss pressure/blockages...? But would that be so precise, as in same revs in every gear etc...?
If not fuel then maybe management, but no "check light" and manual code reads clear.
Any ideas...?
Cheers Rich.
PS: Oxygen sensor is new too.
#6
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Try disconnecting the Apexi and rejoining the MAF wires mate.
Deffo sounds airflow related, had the same prob on a Pulsar last year. Would clear with the Apexi disconnected and the MAF wire reconnected.
Rob
Deffo sounds airflow related, had the same prob on a Pulsar last year. Would clear with the Apexi disconnected and the MAF wire reconnected.
Rob
#7
Again thanx,
Apexi was fitted to try and cure this! I originally thought that fitting the air filter and exhaust had buggered up the fueling as problem developed soon after fitting. Since then I returned car to standard at one point to make sure is was not these causing trouble.
Are you sure it sounds airflow...? Surely the boost gauge being plumbed in to the top of the intake manifold would show up any loss of air pressure? Unless it is a MAF/MAP sensor problem? Would this not put on the check light...?
Rich.
Apexi was fitted to try and cure this! I originally thought that fitting the air filter and exhaust had buggered up the fueling as problem developed soon after fitting. Since then I returned car to standard at one point to make sure is was not these causing trouble.
Are you sure it sounds airflow...? Surely the boost gauge being plumbed in to the top of the intake manifold would show up any loss of air pressure? Unless it is a MAF/MAP sensor problem? Would this not put on the check light...?
Rich.
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#8
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The boost gauge will only read positive pressure in the system it will not show any airflow deviations.
You wont get CEL.
I had the same prob on my car, addmittedly it was due to too much airflow which you wont be experiencing but the symptoms were very similar making me think it was airflow related.
Might be worth changing your fuel filter as well.
Rob.
You wont get CEL.
I had the same prob on my car, addmittedly it was due to too much airflow which you wont be experiencing but the symptoms were very similar making me think it was airflow related.
Might be worth changing your fuel filter as well.
Rob.
#9
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Check the air signal line to your fuel pressure regulator, if this is off or leaking it will cause severe misfire coming on to boost. Unplug it at the manifold end and blow along it, there should be no leakage.
#10
Cheers Rob,
I get your point about boost gauge.
It has occurred that MAF must be working, as Apexi airflow readings are OK, is that correct?
Fuel filter is not that old, but good call, worth changing just to make sure.
Rich.
I get your point about boost gauge.
It has occurred that MAF must be working, as Apexi airflow readings are OK, is that correct?
Fuel filter is not that old, but good call, worth changing just to make sure.
Rich.
#11
Andy,
That sounds hopefull, it does seem to come on just as turbo is spooling up. Will try that tonight, along with fitting new fuel filter.
Cheers, any more suggestions to keep me from my dinner tonight?
Rich
That sounds hopefull, it does seem to come on just as turbo is spooling up. Will try that tonight, along with fitting new fuel filter.
Cheers, any more suggestions to keep me from my dinner tonight?
Rich
#12
Have you got the standard fuel pump? the ones on the uk cars were never the best to start with.
A friend had a similar problem before his engine blew up, but after fitting another engine the problem was still there, turned out to be the fuel pump.
A friend had a similar problem before his engine blew up, but after fitting another engine the problem was still there, turned out to be the fuel pump.
#13
Cheers wanted (good name!)
Will take my fuel pressure tester home tonight. The frustrating thing is I work in a large garage and was previously a mechanic. But I have never worked on Subaru and nor have any of my (9) technicians.
I am a bit of a running joke here at the moment!!
I need to save face badly!!
Thanx, Rich
Will take my fuel pressure tester home tonight. The frustrating thing is I work in a large garage and was previously a mechanic. But I have never worked on Subaru and nor have any of my (9) technicians.
I am a bit of a running joke here at the moment!!
I need to save face badly!!
Thanx, Rich
#14
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The fuel pressure tester should point you in the right direction
You are looking for approx 3 bar with the engine off. 2.3 bar at hot idle and 4 bar at 1 bar boost pressure.
Andy
You are looking for approx 3 bar with the engine off. 2.3 bar at hot idle and 4 bar at 1 bar boost pressure.
Andy
#16
mate of mine has exactly the same prob on my99 turbo. has tried everything. latest one is perished fuel lines causing blockages in filter at high demand!! he is gutted had car 6 months and hasn't been able to use it yet.
#17
Have followed all recommendations, thanks guys, unfortunately no joy.
Air signal line for pressure regulator OK, no leaks.
Replaced fuel filter, checked fuel pressure before and after replacement, both readings the same.
Two possibilities come to mind:
Max fuel pressure at about 0.8bar boost (full throttle) was nearer 3.5bar than 4, but held steady OK, is this significant?
The other is does anyone know if the purge canister next to the radiator has a pipe connected to the single outlet on the bottom, mine does, but it is only a pipe venting to atmosphere, ie not attached to anything (I must admit, I have no idea what effect this may or may not have on running)...
Cheers, Rich
Air signal line for pressure regulator OK, no leaks.
Replaced fuel filter, checked fuel pressure before and after replacement, both readings the same.
Two possibilities come to mind:
Max fuel pressure at about 0.8bar boost (full throttle) was nearer 3.5bar than 4, but held steady OK, is this significant?
The other is does anyone know if the purge canister next to the radiator has a pipe connected to the single outlet on the bottom, mine does, but it is only a pipe venting to atmosphere, ie not attached to anything (I must admit, I have no idea what effect this may or may not have on running)...
Cheers, Rich
#18
Can u post a pic off your Engine . Friend had same problem and he told me how to cure it but i need a pic off the o/s engine around about strut side to point you in the direction as i dont or carnt tell you till i see it. I know it sounds daft but it cured is , Put pic up or E mail me pic as per profile i may be able to help.
Steve
#24
Morning,
Steve: Thanks for the advise to clean out boost control solenoid (I worked out what it is!), didn't work I'm afraid, but cheers anyway, it's another thing checked.
Dickie: Cheers for the offer, really good of you, but Shropshire e-mailed me a description and we sorted it (see above).
Giving up now everyone, booked into Xtreme Scoobys saturday, will post how I got on...
Thank you to all who replied, the scoobynet certainly tries very hard to help!
Thanks again, Rich
Steve: Thanks for the advise to clean out boost control solenoid (I worked out what it is!), didn't work I'm afraid, but cheers anyway, it's another thing checked.
Dickie: Cheers for the offer, really good of you, but Shropshire e-mailed me a description and we sorted it (see above).
Giving up now everyone, booked into Xtreme Scoobys saturday, will post how I got on...
Thank you to all who replied, the scoobynet certainly tries very hard to help!
Thanks again, Rich
#25
Sorry mate. Let us know please what problem was . Pretty much guarantee it will happen to someone else here. Hope it dont cost to many £ to put right.
On the plus side think how much money you saved on Petrol .lol.Be able to go and buy her indoors something .
Steve
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