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Engine reassembly, now back fire?

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Old Mar 29, 2012 | 12:36 AM
  #21  
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I took the whole bracket off... and put the whole bracket back on.. idk how I could have switched it because the clip of the plug is facing up right? I don't know... I never changed the order of the coils, unless I flipped the whole bracket, which I don't see happening since the clip would be facing down.
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Old Mar 29, 2012 | 12:38 AM
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hard to say... but, its not the switching of the coils, its hanging the coil plug in wires over the intake to get them out of the way, then just twisting them and plugging them back in backwards in the coils. Its kinda hard to do but as u can see, a few of us have done it.
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Old Mar 29, 2012 | 12:44 AM
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Originally Posted by waterbug1999
hard to say... but, its not the switching of the coils, its hanging the coil plug in wires over the intake to get them out of the way, then just twisting them and plugging them back in backwards in the coils. Its kinda hard to do but as u can see, a few of us have done it.
I guess so.. I can't wait to get back home and look at it.. hopefully its that easy.
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Old Mar 29, 2012 | 03:53 PM
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Originally Posted by Fosnot
I guess so.. I can't wait to get back home and look at it.. hopefully its that easy.


Yes, just verify the color codes and you'll be fine.
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Old Mar 29, 2012 | 06:02 PM
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I even put a piece of tape on my harnesses telling me which one is which and which way it goes. Somehow, i still had the passenger side turned around. rofl
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Old Mar 29, 2012 | 06:11 PM
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Originally Posted by LS1WS6dreamer
I even put a piece of tape on my harnesses telling me which one is which and which way it goes. Somehow, i still had the passenger side turned around. rofl
I've got mine off right now, and taped and numbered the #8, & #7, respectively.
Just the same, I'll verify them again before reinstalling.
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Old Mar 30, 2012 | 09:33 PM
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Originally Posted by waterbug1999
i did that when i did my build, but had them both *** backwards and the car wouldnt even start and backfired while cranking it. I eventually got smart and flipped them all around. If u have it like that with one side it will start and backfire.

Make more since?



The bracket only goes on one way... and the plug to the coils faces up, so I don't see how I could put it reverse like that (as in face down, right?)

I went and switched the coil brackets to the opposite sides to try and remedy the problem. I didn't let it idle long enough to start backfiring, but the check gauges light still flickered on and off(as mentioned before almost like a shorted out light bulb, really inconsistent)
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Old Mar 30, 2012 | 09:38 PM
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Not to beat the dead horse...did you verify the colors? It's really the only thing that matters.
Anything else is chance.
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Old Mar 30, 2012 | 09:48 PM
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Originally Posted by gMAG
Not to beat the dead horse...did you verify the colors? It's really the only thing that matters.
Anything else is chance.
I checked the wires on the harness, that plugged into the coil bracket plug(the one in the same loop as the plugs that connect to the fuel injectors) and the driver's side does have a brown, and the passenger side does have a brown/white wire. As said back on page 1, that is right... correct?
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Old Mar 30, 2012 | 10:01 PM
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Originally Posted by Fosnot
The bracket only goes on one way... and the plug to the coils faces up, so I don't see how I could put it reverse like that (as in face down, right?)

I went and switched the coil brackets to the opposite sides to try and remedy the problem. I didn't let it idle long enough to start backfiring, but the check gauges light still flickered on and off(as mentioned before almost like a shorted out light bulb, really inconsistent)
if ur saying it has to warm up to start backfiring then its not ur problem, if u have this backwards it will do it right away.

If u unplug each connection from each coil pack and grab that main connection up under the fuel rail and twist it you can flip the order completely around. Nothing to do with the coil pack order.
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Old Mar 30, 2012 | 10:08 PM
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Alright.. I feel like I'm just not understanding something here, here is the drivers side.. how would I twist it to rearrange firing order. I feel like I'm looking right at it, but can't identify the problem.
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Old Mar 30, 2012 | 10:40 PM
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Not sure what was done to the car prior to purchasing it, but it does have a coil bracket, and center bolt valve covers(thought only 99's had that? Maybe I'm wrong. See link)

But as its shown in this thread: https://ls1tech.com/forums/generatio...ed-my-cam.html

you can put them in backwards.. I just don't understand how to put the whole bracket in backwards as in faced down?

I'm waiting for this 'ah.. ha!' moment to come punch me in the face, hard.
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Old Mar 30, 2012 | 10:54 PM
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like said above, if ur saying u have to let it run awhile before it backfires then this isnt ur issue.. if it was it would backfire as soon as it started.
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Old Mar 30, 2012 | 11:01 PM
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Originally Posted by waterbug1999
like said above, if ur saying u have to let it run awhile before it backfires then this isnt ur issue.. if it was it would backfire as soon as it started.
Would the same apply to plugs/wires? And the check gauges light flickers immediately..

Just trying to think why it would suddenly do this if it wasn't a plug, a wire, a coil, or misinstalled coil bracket.

I don't think an O2 sensor would cause this would it?

O2 sees there is a cylinder not firing by oxygen content in exhaust, riches up fuel to compensate. Whats causings the misfire?
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Old Mar 30, 2012 | 11:34 PM
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Originally Posted by Fosnot
Would the same apply to plugs/wires? And the check gauges light flickers immediately..

Just trying to think why it would suddenly do this if it wasn't a plug, a wire, a coil, or misinstalled coil bracket.

I don't think an O2 sensor would cause this would it?

O2 sees there is a cylinder not firing by oxygen content in exhaust, riches up fuel to compensate. Whats causings the misfire?
Lets start over here...

What is the car doing? Have u pulled codes? What did you do to get here?
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Old Mar 30, 2012 | 11:57 PM
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The car is not throwing codes(no SES light), but it has a bad misfire (regardless of temp [closed vs open loop]).
Idling is somewhat rougher (more so than it was prior to fixing the head gasket on the other side of the engine). Prior to the head gasket going out on the passenger side the car ran great with the cam/heads combo. Now it has a random shotgun like backfire out of the exhaust (driver's side [dual exhaust that dumps to verify]) while idling.

While driving you notice the miss, while idling the check gauges light flickers randomly/inconsistently; if you apply throttle to the engine without a load the light stops flickering and goes off.


When I did the head gasket on the passenger side, I took the headers off the drivers side so I could torque the headbolts down to the correct spec (didn't quite go far enough the first time) which makes me wonder if a spark plug might have gotten nixed?

I did have both coil brackets off, one did get knocked over as it was standing tall against the wall (coil got nixed? idk)
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Old Mar 31, 2012 | 12:06 AM
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So u say it has a bad misfire.. then u go drive it and u notice a miss?

things i would go thru, double check you have all your plug wires in all the way, might even throw a new set up plugs in first if you think u damaged one. Also, check the ground wires in the back of the heads to make sure they are tight. Make sure all the wires are nice and snugg/snapped in place.. Coolant sensor reading/working right?
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Old Mar 31, 2012 | 12:12 AM
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Not sure what it has at idle.. just rougher. When driven is when you can feel the miss(es).

I guess I'll take the spark plugs out and see. Never hurts to replace them I suppose, I did verify and reverify that the wires were on snug and snapped in.

The coolant sensor is less than a year old, replaced that after the fans wouldn't come on over the summer
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Old Mar 31, 2012 | 12:16 AM
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yea, I would start there. Inspect the plug wires, sometimes the break where the clip onto the plugs.
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Old Mar 31, 2012 | 12:55 AM
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Well I took all the spark plugs off the driver's side, low and behold the plug in very back has a cracked base (2 hairline cracks from the contact point to the hex base). I guess I'll get the coils tested while I'm at the auto parts store just in case.

The other crack is just on the otherside right out of view of the camera. Both about this size.


In case there is still an issue after the plug replacement (and coil test come back clean?)
Any other suggestions?

Last edited by Fosnot; Mar 31, 2012 at 01:07 AM.
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