Car will not start after replacing intake manifold gaskets

Hi Martinez,

An engine needs three things to start and run, fuel, spark, and compression. You said you checked fuel and spark, and I assume you are saying that you have them. If so, have you checked compression? Let me know what the compression is for each cylinder and just confirm for me that you do in fact have fuel and spark.

https://www.2carpros.com/articles/how-to-test-engine-compression

Also, was the engine running before you replaced the intake gaskets? I am wondering if the plugs are fouled from fuel due to cranking and not firing. This will cause the plugs to not be able to deliver the spark and it will just crank. If this has been cranking for a while and the injectors are spraying fuel, you may want to change out the plugs just to be sure they are not causing the issue.

Okay. So if you have compression but it just cranks then you are missing one of the other two. Fuel or spark.

I would put a fuel pressure gauge on it while cranking and see what the pressure is while cranking. It needs to be sufficiently high to fire the engine. Then when you checked for spark did you pull the plugs and ground them against the block to check for spark?

If you have all three then the engine should start.

If all you did was change intake gaskets and now it doesn’t start the only other thing I can think is you have a large intake leak allowing to much unmetered air in the engine so you air fuel mixture is way too lean.

At this point this may not be related to the manifold gaskets as the hose collapsing is most likely a vacuum in the cooling system or a faulty radiator cap.

so, we need to check the radiator for a restriction and then the cap for a leak.

However, if the engine will not restart, we need to check to find out if we have a head gasket issue as well.

Here is a guide that will help with this:

https://www.2carpros.com/articles/head-gasket-blown-test

There could be something else going on, but we need to start with this and go from there.

Thanks