Diagnosing random powerloss/ gain V6 3.1 91
#1
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Diagnosing random powerloss/ gain V6 3.1 91
He guys
I need some help guidance with this.
Here's the case. I have powerloss issue.
The engine is a little bit vibrating and sounds like 1 cylinder isn't working along quit well. Did a sparkplug test, all 6!nice brownish, replaced 2 sp.wires because the broke off. I notice I don't have the engine that i used to have. The sounds like it has a flutter. Meaning instead of nice 'round' sound, it sounds like there's a little leak
That said, this is what I did so far. The engine worked great when i did a major tune-up few months ago where i changed all sparkplugs, wires, dist. cap, rotor, fuelfilter. I also replaced the stock injectors with Southbay ones. As mentioned, checked all then cables and plugs. Did a vacuumleaktest (at least I tried for the first time) but couldn't find anything.
Today after diagnosing, I went for a spin, engine had powerloss. After 20 minutes all of the sudden i had full power back! The engine sounded normal, had the torque back that i'm used to and it drove great again....for 5 minutes and then it went back to 'bad performance mode😁'
Could it be a vacuumleak i'm not spotting?
What could be a reason for this random powerloss/ gain
What in do know is that i smell gass from time to time as if actually a cylinder isn't firing quit right...or...is it a injector
Any directions are welcome
Thanks!
I need some help guidance with this.
Here's the case. I have powerloss issue.
The engine is a little bit vibrating and sounds like 1 cylinder isn't working along quit well. Did a sparkplug test, all 6!nice brownish, replaced 2 sp.wires because the broke off. I notice I don't have the engine that i used to have. The sounds like it has a flutter. Meaning instead of nice 'round' sound, it sounds like there's a little leak
That said, this is what I did so far. The engine worked great when i did a major tune-up few months ago where i changed all sparkplugs, wires, dist. cap, rotor, fuelfilter. I also replaced the stock injectors with Southbay ones. As mentioned, checked all then cables and plugs. Did a vacuumleaktest (at least I tried for the first time) but couldn't find anything.
Today after diagnosing, I went for a spin, engine had powerloss. After 20 minutes all of the sudden i had full power back! The engine sounded normal, had the torque back that i'm used to and it drove great again....for 5 minutes and then it went back to 'bad performance mode😁'
Could it be a vacuumleak i'm not spotting?
What could be a reason for this random powerloss/ gain
What in do know is that i smell gass from time to time as if actually a cylinder isn't firing quit right...or...is it a injector
Any directions are welcome
Thanks!
Last edited by Donald Croes; 07-23-2016 at 03:16 PM.
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Re: Diagnosing random powerloss/ gain V6 3.1 91
If the original MULTEC injectors are still in the engine replace them. They fail by the coils shorting out, which by now they have to be.
RBob.
RBob.
#4
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Re: Diagnosing random powerloss/ gain V6 3.1 91
Alright, I'm getting somewhere!
Ruled out all ingnition things, they work as it should
Did a another Vacuumleak test. Besides spraying, used pair of pliers to sqeeuze down the lines. Everything is fine.
Then I though about the injectors again. Took a long screwdriver and listened if the injectors are pulsing...and what do you know. Injector on Cyl 3 isn't working properly.
All the other 5 Injectors are making a distinct pulsing sound. The Number 3 Cyl injector makes a pulsing sound, but it isn't that distinct as the other ones. As if the volume was turned down.
So, now that I know that it's the #3 injector. Hope you guys can help me out
Looking at the sparkplug's color, Gass is coming in the cylinder. It's a nice brownish tan
Because I hear a very light pulsing sound, can I conclude that the injector is dirty?
Or could it still be a electrical issue? I.e. that the injector isn't getting enough electricity ergo it hasn't got enough power to pulse? Keep in mind, that when I drove last Saturday. All of the sudden Cylinder 3 came on and I had all bhp back for 5 minutes. After 5 min, the engine dropped back to the bad performance it had.
Thanks!
Ruled out all ingnition things, they work as it should
Did a another Vacuumleak test. Besides spraying, used pair of pliers to sqeeuze down the lines. Everything is fine.
Then I though about the injectors again. Took a long screwdriver and listened if the injectors are pulsing...and what do you know. Injector on Cyl 3 isn't working properly.
All the other 5 Injectors are making a distinct pulsing sound. The Number 3 Cyl injector makes a pulsing sound, but it isn't that distinct as the other ones. As if the volume was turned down.
So, now that I know that it's the #3 injector. Hope you guys can help me out
Looking at the sparkplug's color, Gass is coming in the cylinder. It's a nice brownish tan
Because I hear a very light pulsing sound, can I conclude that the injector is dirty?
Or could it still be a electrical issue? I.e. that the injector isn't getting enough electricity ergo it hasn't got enough power to pulse? Keep in mind, that when I drove last Saturday. All of the sudden Cylinder 3 came on and I had all bhp back for 5 minutes. After 5 min, the engine dropped back to the bad performance it had.
Thanks!
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Re: Diagnosing random powerloss/ gain V6 3.1 91
Not sure how to troubleshoot that except to send the injectors out for cleaning. If you think it could be electrical swap that injector with another and see if it stays on that cylinder or if it moves with the injector.
As for the ignition, check the distributor plate that the cap mounts too. A while back a guy here had it coming loose from the distributor body. Caused issue similar to what you are experiencing.
RBob.
As for the ignition, check the distributor plate that the cap mounts too. A while back a guy here had it coming loose from the distributor body. Caused issue similar to what you are experiencing.
RBob.
#6
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Re: Diagnosing random powerloss/ gain V6 3.1 91
Thanks Rbob,
I'll check the dis.plate before removing the injector. Perhaps the issue is that simple
Do you or anybody know if it's possible /how to only remove the connector from Inject. Cyl 3 without removing the whole intake manifold? I want to check with a noidlight if any pulse is coming through the connector before pulling eveyrhting apart
cheers
I'll check the dis.plate before removing the injector. Perhaps the issue is that simple
Do you or anybody know if it's possible /how to only remove the connector from Inject. Cyl 3 without removing the whole intake manifold? I want to check with a noidlight if any pulse is coming through the connector before pulling eveyrhting apart
cheers
Last edited by Donald Croes; 07-28-2016 at 08:52 AM.
#7
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Re: Diagnosing random powerloss/ gain V6 3.1 91
Well, new update:
Talked to SouthBay and they will send a new injector for me to replace. Now that's what I call customer service! Keep in mind that I just drove 150miles with a whole new set of injectors when one broke down.
The faulty injector actually stopped working completely now. I'm not gonna swap for one of my spairs. There cleand stock injectors, not really my preference. The Bosch 2's rock.
When I Swapped the faulty one, will let you guys know if the issue is fixed!
cheers!
Don
Talked to SouthBay and they will send a new injector for me to replace. Now that's what I call customer service! Keep in mind that I just drove 150miles with a whole new set of injectors when one broke down.
The faulty injector actually stopped working completely now. I'm not gonna swap for one of my spairs. There cleand stock injectors, not really my preference. The Bosch 2's rock.
When I Swapped the faulty one, will let you guys know if the issue is fixed!
cheers!
Don
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#8
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Re: Diagnosing random powerloss/ gain V6 3.1 91 - SOLVED
Well problem solved!
Replaced the faulty injector and the engine runs great again!
Thanks to Southbay Injectors for supplying a free of charge replacement injector, with 16 extra o-rings.
Replaced the faulty injector and the engine runs great again!
Thanks to Southbay Injectors for supplying a free of charge replacement injector, with 16 extra o-rings.
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Re: Diagnosing random powerloss/ gain V6 3.1 91
Hi there,
Nice to hear it is working again. Have fun!
Nice to hear it is working again. Have fun!
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