Nightmare diagnosing n54

Msport335

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Jun 7, 2018
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Everything was done correctly during install ...no gunk , no oil or anything as far as debris in the way.

What' easiest way to test for vacuum leak ?
 
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matreyia

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Everything was done correctly during install ...no gunk , no oil or anything as far as debris in the way.

What' easiest way to test for vacuum leak ?

I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.

Your tmap was not disconnected at any time during this situation? Also the intake manifold was not removed and then replaced? If so, were the manifold gaskets replaced as best practice?
 

Msport335

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Jun 7, 2018
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I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.

Your tmap was not disconnected at any time during this situation? Also the intake manifold was not removed and then replaced? If so, were the manifold gaskets replaced as best r
I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.

Your tmap was not disconnected at any time during this situation? Also the intake manifold was not removed and then replaced? If so, were the manifold gaskets replaced as best practice?
I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.

Your tmap was not disconnected at any time during this situation? Also the intake manifold was not removed and then replaced? If so, were the manifold gaskets replaced as best practice?
I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.

Your tmap was not disconnected at any time during this situation? Also the intake manifold was not removed and then replaced? If so, were the manifold gaskets replaced as best practice?
Tmap and intake manifold left untouched...i will be getting walnut blast done tomorrow. I did undo the connector on the tmap when I removed charge pipe when replacing the lpfp sensor
 
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fmorelli

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I would not bother. What I did was purchase 11 ft of 500°f silicon hose an replaced all stock crackly hoses. Takes about an hr to do all hoses. It is more time and effort to test for leaks.
This is wise advice. Especially as these cars get older. Make sure, when you replace lines, that you don't cause any strain points due to having too short a length - I've found that accelerates the hose demise. No curvy bends.

A few links and tips that might be helpful:

Somewhere I saw mention of titanium lace silicone line (?!) ... Internet fable? Can't find anything about it.

Filippo
 
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fmorelli

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I've also seen some folks say, when going to silicone, that the 4mm line works much better than 3.5mm, when fitting on barbs?

Filippo
 

The Convert

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I've also seen some folks say, when going to silicone, that the 4mm line works much better than 3.5mm, when fitting on barbs?

Filippo
That may be, but bottom line, 6mm or 1/4" with an npt-barb fitting added to your IM is what you want.
 

kayzrx82

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I had the same issue with my car . Injectors were fine, new coils with new plugs. Mine turned out to be a loose ground on the harness that screws onto the post that secures the valve cover. Go over the grounds in that area with and ohm meter and make sure they are connected right. Then use an ohm meter and check the grounds to the pins of the injectors and coils. 2 other cars I worked on had similar issues with rough idle and misfires that were due to connection issues.

Also how clean are your intake valves? Carbon buildup on the valves can cause rough idle.
 
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Msport335

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Jun 7, 2018
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I had the same issue with my car . Injectors were fine, new coils with new plugs. Mine turned out to be a loose ground on the harness the screws onto the post that secures the valve cover. Go over the grounds in that area with and ohm meter and make sure they are connected right. Then use an ohm meter and check the grounds to the pins of the injectors and coils. 2 other cars I worked on had similar issues with rough idle and misfires that were due to connection issues.

Also how clean are your intake valves? Carbon buildup on the valves can cause rough idle.

Car is at the shop as we speak getting carbon blast ....took a look when intake was off just now and they weren't that bad at all ..bit of gunk on valve stems.

Guess I'll check grounds next...can you possibly post a pic of the ground your speaking of ?

Thanks
 
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JuniorB

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This may be a shot in the dark, but what are the chances new index 12 are giving you the issues, same with coils and plugs. When was the last time you done a software update? If all your hardware has been changed with no results, look into other avenues.
 

Msport335

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Jun 7, 2018
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This may be a shot in the dark, but what are the chances new index 12 are giving you the issues, same with coils and plugs. When was the last time you done a software update? If all your hardware has been changed with no results, look into other avenues.
Software is up to date.... hard to narrow down to bad injectors plugs or coils which are all new and not throwing any codes now however still getting cold start stumbles
 
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kayzrx82

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Apr 4, 2018
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Car is at the shop as we speak getting carbon blast ....took a look when intake was off just now and they weren't that bad at all ..bit of gunk on valve stems.

Guess I'll check grounds next...can you possibly post a pic of the ground your speaking of ?

Thanks
Heres an image from Rokatek
valve21.jpg
 

BMSTATION

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May 9, 2018
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I came across sticky lifters, head gasket leaking through cylinder over night, water inside DME box or piston rings.

Have 6x long screw drivers inside your freezer, Warm the car up to normal temps make sure you coolant pipes are hard, take out your spark plugs immediately and get your screw drivers and insert them inside your spark plug holes, count approx 15 seconds and start lifting one by one, if you see condensation on one or more screw drivers that will be head gasket otherwise next step...
 

matreyia

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I came across sticky lifters, head gasket leaking through cylinder over night, water inside DME box or piston rings.

Have 6x long screw drivers inside your freezer, Warm the car up to normal temps make sure you coolant pipes are hard, take out your spark plugs immediately and get your screw drivers and insert them inside your spark plug holes, count approx 15 seconds and start lifting one by one, if you see condensation on one or more screw drivers that will be head gasket otherwise next step...


Explain how you came across this procedure and from what source. Also explain the reasoning behind it.

If you cool down any metal in a freezer, and take it out into a hot environment, there will be condensation by the law of physics.
 
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kayzrx82

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Apr 4, 2018
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I came across sticky lifters, head gasket leaking through cylinder over night, water inside DME box or piston rings.

Have 6x long screw drivers inside your freezer, Warm the car up to normal temps make sure you coolant pipes are hard, take out your spark plugs immediately and get your screw drivers and insert them inside your spark plug holes, count approx 15 seconds and start lifting one by one, if you see condensation on one or more screw drivers that will be head gasket otherwise next step...

Ive never heard of this as a method to check for a leaking head gasket. Usually just pressure test the cooling system with a gauge. If the leak was bad enough to cause condensation on a cold screwdriver that quick, the car would be running very rough and have alot of steam coming out the exhaust. Also the coolant would be running low needing constant top offs.
 

matreyia

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Ive never heard of this as a method to check for a leaking head gasket. Usually just pressure test the cooling system with a gauge. If the leak was bad enough to cause condensation on a cold screwdriver that quick, the car would be running very rough and have alot of steam coming out the exhaust. Also the coolant would be running low needing constant top offs.


@BMSTATION:

Again, you do realize that condensation will happen on any cold surface when exposed to hot environments? If you put those screwdrivers into a heated oven, it would do the very same thing in the same amount of time. Your logic/reasoning for this test that you devised is not based on verifiable incontrovertible cause and effect. That is to say, condensation on a cold surface will happen regardless of whether or not you place it in the hole or next to the hot engine. And your explanation is incomplete, unsound and illogical.

You asked the person to stick the driver into an open spark plug hole - which means the car is not running. no steam, no exhaust, no spark plugs, no engine running. Finally, leaking oil or coolant has nothing to do with condensation, and what do you think is worse? The leaks on a head gasket or the giant park plug hole that you asked the person to stick the screw driver into?

I don't usually address people negatively initially, but you sir, are wasting people's time who need genuine help. And you will cause catastrophic damage if they follow your incoherent advice. I find your post offensive to any person with a mind and passed high school physics.

Now if you want to properly explain something that I missed in a rational and scientific way...please do so and I will stand corrected. But if you have nothing else besides this "bro-science" and you hunch, then you don't need to go any further.
 
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