|
|
|
|
Thread Tools | Display Modes |
05-18-2017, 11:19 AM | #1 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
No injector pulse on Number 1 cylinder at idle. 1999 ej25
1999 Subaru Legacy Outback. There is no injector pulse at the number 1 injector at idle. When you rev up to about 2000 or 2500 rpm a pulse comes in but it is not normal. So I have redone the timing belt and the timing is absolutely perfect. Tone rings are ok on crank and the pickups on the cam seem to be ok as well. I am absolutely stumped on this problem can someone please point me in the right direction?
* Registered users of the site do not see these ads.
|
05-18-2017, 05:13 PM | #2 |
Scooby Specialist
Member#: 80465
Join Date: Jan 2005
Chapter/Region:
RMIC
Location: Denver
Vehicle:2001 2.5RS Black Diamond Pearl |
could be in the wiring. how does the signal look at the ECU?
|
05-18-2017, 06:23 PM | #3 |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
I would think if it was timing or a sensor, all cylinders would have issues, since it's only 1, I would check connection to the injector, injector wiring, then ECU/MPFI control unit.
|
05-18-2017, 10:31 PM | #4 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
Well I don't fully understand how the ecu grounds the injectors. I have a wiring diagram and I guess they all have a common 12v which is the yellow wire I think but don't remember. Then for the number 1 injector it is a brown wire that goes back to the ecu and this wire has 12v coming out of the ecu. I would think that the ecu would ground this brown wire this giving it its pulse but am unsure. The timing had jumped due to a bad tensioner and I thought this was the problem but after installing new tensioner and timing belt the timing is exact. Not even off a half tooth anywhere. I used the marks but also counted the teeth and it is exact. If it was a bad cam or crank sensor I would think that it would have no spark or at least effect other cylinders. So where do I go from here? The only code I'm having is p0505 and that is because I loosened the screws and adjusted the top part of the iacv. This problem existed before I did that and got that code so I am pretty sure it's unrelated I could be wrong though. I am a lead technician in a shop and this problem is embarrassing me so any help is greatly appreciated. Thanks.
|
05-18-2017, 10:33 PM | #5 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
And like I said the weird part is when I rev it up the misfire smooths out and the injector gets a pulse.... so wtf is that about????
|
05-18-2017, 11:55 PM | #6 |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Last diagram I have is a 96, but I believe yours is the same (other than maybe colors).
Key on feeds power through the ignition relay 12VDC), then to the injectors (common power) and then to the MPFI control unit. This unit then completes the circuit for each injector as needed by connecting to ground. Thus yes, you should have constant power TO each injector, but they won't fire until they are grounded. So if you have consistent power to the injectors, then check the connections at the injector and then follow along back to the MPFI. A bad connection may get better with the additional vibration of higher revs. I reLly don't think it's a "brain problem". I think wiring is more likely. When did this issue start? Was it before or after the jumped timing? Has any other work been done? |
05-19-2017, 02:48 AM | #7 |
Scooby Newbie
Member#: 3409
Join Date: Jan 2001
Chapter/Region:
NWIC
Location: Oly
Vehicle:98 My FMIC Is bigger than yours. |
Ehhhh.
If you've got good battery voltage at the injector wire at the ECU, I'd wager the harness is OK. Sounds like it's ECU internal to me. Easy enough to test, though. Take your NOID light and run a power wire to a known good B+, then pull the #1 injector wire from the ECU and run a wire from the NOID light to the ECU pin. If you've got a good steady flash, then yes, it's an issue with the wiring or injector. If there's no flash, you've eliminated everything but the ECU as your issue. |
05-19-2017, 02:58 AM | #8 | |
Scooby Newbie
Member#: 3409
Join Date: Jan 2001
Chapter/Region:
NWIC
Location: Oly
Vehicle:98 My FMIC Is bigger than yours. |
Quote:
The 12v you measured at the ECU isn't coming from the ECU, it's coming from the injector. Until the ECU grounds the circuit, it's an incomplete circuit and there will be battery voltage present from one end to the other, generally speaking. If you were to unplug the injector, and measure at the ECU again, it should have no voltage, and no continuity to ground (unless the engine were spinning, then you would ideally see intermittent continuity to ground). |
|
05-19-2017, 08:41 AM | #9 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
Well then I think I have found the problem and that being the ECU. The car was running ok and then parked for a long time and when it was started up after the long sit down the timing jumped. So no other work done. I can take my probe right at the ecu and no ground comes. Solid 12v. So being as the ECU is supposed to be sending my ground to complete the circuit and it is not sending anything, directly at the ECU connector, that has to be the problem then? Charlie-III like I said Im working in the shop I have napa prolink which is similar to alldata so any and all diagrams are available to me so if you or anyone else ever needs one shoot me a PM or something. And thanks for all the help and suggestions. So being as how my ecu is not sending my ground, directly out of the ECU that pretty much eliminates everything as the problem then?
|
05-19-2017, 08:50 AM | #10 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
Ok just to verify I clipped the wire that is supposed to be the ground for number 1 injector directly at the ECU and there is no pulse at idle. The strange thing is when I give it some gas a pulse comes. So is ECU the consensus or what? I also just realized that it is the same story for the number 2 injector. No pulse at idle, give it some gas, and the pulse comes.
|
05-19-2017, 08:53 AM | #11 |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Thanks Cosmo for he additional info, I figured wiring would be similar.
Question, the MPFI I see in my diagram, is that the ECU, part of the ECU or a separate box? Mantis, sounds like you got it. By chance, is the interior damp or wet? High humidity could make an issue with the ECU. As to Alldata, I work PT at a local shop and they have Identifix I can access, but thanks for the offer. Curious why is would just die like that........ |
05-19-2017, 09:01 AM | #12 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
No moisture at all... I just took out the ECU and took the cover off, I cant see anything burnt but it does have a bad burnt electrical smell to it...
|
05-19-2017, 11:05 AM | #13 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
ok so heres a funny thing. update. i notice the temperature sensor is pegged all the way hot even though the engine is not hot. So I notice in my wiring diagram the throttle position sensor and the coolant temp sensor share a common ground. so i unplugged the throttle position sensor and the pulse comes back and it runs fine...
|
05-19-2017, 03:28 PM | #14 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
temperature sensor was unplugged plugged it in makes no difference on the misfire. if i unplug TPS runs great once i plug it in back to misfiring.
|
05-19-2017, 03:48 PM | #15 | |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Quote:
|
|
05-22-2017, 08:32 AM | #16 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
Ok so why does it misfire all over the place and run like crap until I unplug the TPS? If I unplug the MAF it dies. And the temperature gauge and fans are working properly.
|
05-22-2017, 08:41 AM | #17 | |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Quote:
BTW, since it sat a while, are there signs of chipmunks or mice? Things like acorn shells, balls of insulation, droppings, etc? When I get a chance, I will look up the diagrams to see if something makes sense. |
|
05-22-2017, 09:38 AM | #18 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
No, no signs of mice. Thank you.
|
05-25-2017, 08:16 PM | #19 |
Scooby Specialist
Member#: 59182
Join Date: Apr 2004
Location: N. Idaho
Vehicle:2002 WRX GG>> 2016 Focus RS |
>>>>and NO codes (CEL)? Or did I miss that?
|
05-26-2017, 04:06 PM | #20 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
idle air control valve p0505 but that didnt come up until i took the motor off of the valve. it is adjustable and i guess i just didnt put it back in the same position as it was before. so the problem existed before and after the code.
|
05-26-2017, 04:07 PM | #21 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
and it is an lj25 not ej25 my mistake...
|
06-01-2017, 10:50 AM | #22 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
so everyone is stumped huh
|
06-04-2017, 12:19 AM | #23 |
Scooby Newbie
Member#: 468750
Join Date: Jun 2017
|
having the same issue. research tells me its going into a fail safe mode. because of a high idle issue. when in fail safe #1 and #2 injector shut off. Im still researching the issue as we speak.
|
06-08-2017, 10:16 AM | #24 |
Scooby Newbie
Member#: 467886
Join Date: May 2017
Location: Baltimore
Vehicle:1999 legacy outback |
interesting. thank you very much i will be interested to hear what you find out
|
06-08-2017, 12:28 PM | #25 | |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Yep, you got me on this one.
Quote:
|
|
Thread Tools | |
Display Modes | |
|
|