3400 shoots fire back out the intake [Archive] - GrandAmGT.com Forum


View Full Version : 3400 shoots fire back out the intake

08-10-2011, 08:32 AM
I just rebuilt my 3400 and put in a cam timing is dead on I got 150psi in each clinder what can it be I curled the cam it is right on time I got fuel and I got spark as well??????

08-10-2011, 09:09 AM
stock cam? sticky valve? ignition timing?

08-10-2011, 09:18 AM
Actually sounds like it may be 180 degrees out i could be wrong but thats what it sounds like to me just by your description i hope thats not the prob, the cam was timed with #1 piston at TDC right ?

08-10-2011, 11:28 AM
Either your cam timing is off or you need to get retuned to change the spark timing.

08-10-2011, 01:04 PM
ok how can i fix the timing problem if it would be 180 ????
how can i change the sprack timing then too if that would be wrong

here is the pictures of my car and what i'm workin on so you'se can see too

08-10-2011, 03:32 PM
You sure you lined up the timing marks correctly? It is possible to mess it up if you aren't paying attention.

The crank gear and cam gears both have key ways on them so obviously it is only possible for those to be in one position on each. You just have to line up the correct marks on both. There are a couple little tabs on the top and bottom edges of the chain damper that help line them up. There is a tooth on the crank gear with a little dimple on the front. That is the crank timing mark. I've seen people mess up thinking the key way was the timing mark, but the dimple is a little off to the side of that. It should be straight up. There is a small hole in the face of the cam gear and that is the other timing mark (it is 90 degrees from the key way). It should be straight down. You could actually have the cam gear turned 180 degrees straight up, and it would still operate correctly, because the crank turns twice for every single revolution of the cam. The manual shows the mark down though for reference, and it's easier to line up the timing marks that way.

08-10-2011, 05:40 PM
Follow Aarons lead to a tee. I bet he has nailed it there

08-10-2011, 07:37 PM
Ok I took off the cover again it is lined up at tdc and I put all back together and it still does the same thing

08-10-2011, 08:58 PM
To have actual fire out the intake your firing with a valve open. There is no chance you mixed up the push rods when you put it back together is there? Sorry, but gotta' ask man

08-14-2011, 11:26 PM
well i think now i know why it is firing out the intake due to my buddy putit on the wrong stoke so on my next day off i will be checkin that out and i hope it fixes the problem and i will get closer to my car back on the road !!!!!!