3L issues, Intake backfire/No spark

[turbo_fox]

Ok I read through all this and in my mind I keep coming back to a vac leak. There has been several good suggestions and seems like most are thinking the same on the vac leak.

How did you test for a leak? I read where you said you sprayed everywhere but what were you spraying? Was the engine running when you did this?

When testing for a vac leak the best method I have found is starting fluid or brake cleaner, I prefer brake cleaner. spray in very small amounts around the gasket areas and if there is a leak you get a change in engine RPM's.

The usual disclaimer applies here, brake cleaner and starting fluid are obviously highly flammable so its a good idea to have a fire extinguisher handy and have you plus at least one other person present for help if needed.

Hope any of this helps.

Brake cleaner also takes paint off so keep that in mind.

 

[zukgod1]

This is true, thus the "spray in very small amounts " part.

Good to point it though for sure..

 

[JnCsvt]

Ive been spraying carb cleaner

The severe blow by possibly indicates bad rings so i have so searching to do, just havnt been able to with weather and work.. hopefully soon

 

[Blackcoog]

Did you pick up a compression tester yet? You should be able to get one for $50 at your local parts store. Try that next.

 

[SHOgoFast]

Ok I read through all this and in my mind I keep coming back to a vac leak. There has been several good suggestions and seems like most are thinking the same on the vac leak.

How did you test for a leak? I read where you said you sprayed everywhere but what were you spraying? Was the engine running when you did this?

When testing for a vac leak the best method I have found is starting fluid or brake cleaner, I prefer brake cleaner. spray in very small amounts around the gasket areas and if there is a leak you get a change in engine RPM's.

The usual disclaimer applies here, brake cleaner and starting fluid are obviously highly flammable so its a good idea to have a fire extinguisher handy and have you plus at least one other person present for help if needed.

Hope any of this helps.

I have serious doubts about how effective this method is for finding vac leaks. I used this on a KNOWN leak point after finding it in different manner and did NOT get a change in engine RPM.

I like to take a ~3ft piece of 3/8" heater hose...put one end up to my ear and probe the other end around places where leaks could be present. Mechanics stethescope. I found vac leaks and exhaust leaks rather easily with this method. Should hear hissing or ticking sounds much more clearly.

I dunno, just my experience.

 

[todras]

What ye say?

 

[SHOgoFast]

What ye say?

It is true, you do get better results when using the hat and cape.

 

[JnCsvt]

Or a smoke machine, ill try that if all else fails.

I did not get to test compression yet, weather has been bad every weekend so far:nonono:

Maybe this weekend though