Intake manifold vacuum leak? - No Start...

[leehyunggyun]

Hi everyone,

I've been battling with this 3400 engine for about 3 months...


Basically, I have replaced intake gaskets and head gaskets and I thought I have installed them correctly.

But when I went to start, the car does not start, unless I give a few push on the pedal, and it idles really roughly.

Also, my OBD scanner shows the intake manifold pressure does not go down. (stays near atmospheric pressure)



So, what can cause this intake vacuum leak / pressure failure?

- I did check the piston and cylinder heads and they didn't have cracks.
- cleaned pistons, but did not apply oils.... (maybe piston ring is too try?)
- lower intake manifold: this was 2nd time doing it, but maybe the studs in the gasket, did not seat properly??


Please let me know if I have missed things / if you have any suggestions / advice!!!

Thanks in advance!