# Fouling cylinders 3 and 4.



## O 16581 72452 5 (Sep 15, 2006)

Basically i have a cluster **** of a swap in my car and can't for the life of me get it running right. Cylinders 3 and 4 are fouling. The motor runs pretty good when i clean the plugs and dry rev it a few times, but as soon as i try driving it i lose a cylinder. After about 15 minutes of driving, i lose another cylinder and the car is basically undrivable at this point. There's also lots of sweet fire coming out the exhaust.

Time to replace 3 and 4 injectors, or any other ideas?


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## ps2375 (Aug 13, 2003)

Injectors would be my guess, seeing as you fail to give any other info.


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## WaterWheels (Aug 14, 2005)

O 16581 72452 5 said:


> . . . Cylinders 3 and 4 are fouling. The motor runs pretty good when i clean the plugs . . . as soon as i try driving it i lose a cylinder. . . After about 15 minutes of driving, i lose another cylinder
> 
> There's also lots of sweet fire coming out the exhaust.


First I have to as the biggest question on my mind, what the heck is "sweet fire"? Sorry if it is just because I'm older and all the younger folks will understand, but for me it just makes no lights go off in my head 

With the above cleared up maybe a better answer or some suggestions can be given, but right now I have more questions then responses. Fouling, how? Is this oil fouling or gasoline fouling? To be honest, once a plug becomes fouled (if it really is) it can be tossed in the trash more times then resued. If it runs OK for a while then I kind of doubt the injectors are causing the problem as they would be bad from the start and not go bad over time. Except for cleaning the plugs, what else have you checked as a possible problem (troubleshooting)? Have you done any testing of the ignition system? Like maybe bad wires on cylinders 3 and 4? If it is oil and not gasoline then other thing will have to be looked into. Compression, is it good enough in all cylinders? Correct plugs?

Like ps2375 states, you just don't provide much to work with.


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## O 16581 72452 5 (Sep 15, 2006)

The "sweet fire" part was a joke, i'm basically getting gas dumped in the exhaust and there's pretty much a constant fireball coming out of the tailpipe.

I traced it down to the injectors last night, i swapped them around to different cylinders then lost those cylinders.


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## nbvwfan (Aug 15, 2007)

Do a spray test and measure volume, this would at least verify it is only the injectors. If it is not, there are ways to adjust the metering at individual ports, though no one talks about it.

Buy 4 two liters bottles.
Drill the caps out
Pull the injectors.. you can figure out most of the rest.

I have found an overnight soak in MEK and then air blast helps clear them out. though it will ruin the injector o rings.


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## O 16581 72452 5 (Sep 15, 2006)

I spray tested and one was horrible.

I purchased new injectors.


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## O 16581 72452 5 (Sep 15, 2006)

I spray tested and one was horrible.

I purchased replacement injectors.


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## nbvwfan (Aug 15, 2007)

Did you by chance do a volume check?
If you had two cylinders going out it may be related to your fuel distributor delivery.


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## O 16581 72452 5 (Sep 15, 2006)

I'm thinking it's just the one spraying bad and i'm giving the engine more throttle than i should to compensate for lack of power, then it's flooding another cylinder.

This car is a mess. :facepalm:


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## nbvwfan (Aug 15, 2007)

While spray testing you could also determine if your fuel meter is delivery equal fuel to the injectors.
On my "unworked" 8V fuel meter, I found that average fuel delivery @ full bore for three minutes was about 550-600cc's
With some cleaning at the inlet and outlet fuel ports and plunger bore (without opening it up) and (not easily explained) internally "working" the individual metering lower chamber calibration ports I got my meter to deliver a solid 620cc average and my flow variance to under 4%.


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