cracked manifold harmful?

[gunnmetal]

heres my story:
bought a 1995 shell GS
but a 97 engine(got screwd hard) smoking leaking oil
got all seals,gaskets,belt replaced
1 injector replaced intake cleaned

cracked manifold....
whats next????????

listen whos got a 2g manifold in mint condition for sale.

 

[Enigma_Man]

It depends on the manifold:

Intake Manifold:
You'll run lean with vacuum, rich under boost. Get it fixed ASAP, if it's a large crack, don't drive the car like this.

Exhaust Manifold:
Not a huge problem, it happens. It can cause a lag in boost, lower your maximum possible boost, and eventually causes a mess around the cracked area. A good idea to fix if you have the time, or are doing something in the area anyway.

-Jesse

 

[gunnmetal]

its the exaust manifold
but my car is N/T
is it a big problem?

 

[Enigma_Man]

Nah, it's not a huge problem. Your car will just be a little louder, and probably slightly less powerful, and you'll get a little more heat in the engine bay.

-Jesse

 

[gunnmetal]

everything you said it true it is kinda hot in the engine bay
thanks a lot
as for the power im getting my car back today new vavle seals and head gasket replaced no mor leaking oil and no more smoking ( i hope so)

 

[set3422]

i agree, but have to elaborate more. If it leaks near intake runner 3 & 4, your car would run exactly what Jesse described.

However if it leaks near runner 1 & 2, your car will run lean at idle, part throtlle, and WOT (basically running lean entire fuel curve). Why? If you get leaks near 1 & 2, fuel pressure would drop because FPR vac line connects to intake runner 2. I ran like this for 1 month and guess what cylinder 1 & 2 loss 15 psi compression (down to 145psi). Good luck.

Originally posted by Enigma_Man
It depends on the manifold:

Intake Manifold:
You'll run lean with vacuum, rich under boost. Get it fixed ASAP, if it's a large crack, don't drive the car like this.

Exhaust Manifold:
Not a huge problem, it happens. It can cause a lag in boost, lower your maximum possible boost, and eventually causes a mess around the cracked area. A good idea to fix if you have the time, or are doing something in the area anyway.

-Jesse