5.7 hemi heads milled .015, ported and polished need help!

[6car6nage6]

Hey all,

I'm new here, got a problem. I have a 2004 1500 4x4 with a 5.7 hemi. I got the heads resurfaced, milled .015" and ported and polished. It's got everything else stock. The mechanic also put spacers on the valve springs. The problem I am having is the truck will not idle now, sounds damn good with the rpm's at 1000 but dies when I let off the pedal. Does anyone have a suggestion as to why it will not idle? Thanks in advance.

 

[avantiguy]

Check for engine codes. There's probably something not connected. Usually they fail into limp mode and will run badly but not always.

Also check for vacuum leaks.

The computer shouldn't have any idea of the changes you made.

 

[6car6nage6]

Thanks, that's the frustrating part lol I checked for codes and nothing came up, sorry I should've mentioned that earlier.

 

[6car6nage6]

Couldnt find any vacuum leaks. If it is in limp mode how do you get it out?

 

[RedSRT4Me]

Check cam timing??

 

[2010 Infantry Vet]

You need to have your truck dyno tuned it sounds like to me.

 

[Joshwaa]

Did you get new pushrods? If not your valves might not closing all the way. That will allow it to run with RPM's but will not idle. However only taking off .4mm should not be that much off I would think. Maybe start by having a tune done for the higher flow rate of the head and if that doesn't do it consider pushrods.

Doing a compression test would probably be a easy way to find out.

Also check for intake leaks where intake meets the head. Did you use thinner than the stock head gaskets? That would compound on the milling you did.

 

[6car6nage6]

I did get new pushrods, I do need to check compression. It's got stock replacement head gaskets. I didnt get new intake gaskets though, the mechanic said they didnt need to be replaced. As far as timing, I was gonna get cam some point in time in the future when I get more $ up. I talked to a shop that said they do tunes but will be $1,000 to $1,200. After hearing that, I hope it doesnt need a tune. Does anybody in GA know of a place to tune this cheaper? Thanks for all the help guys!

 

[Joshwaa]

Contact Sean (Hemifever) he is great to work with for tunes. Do you already have a tuner for your truck? Did you get the same size pushrods?

 

[JimGregory]

I would start at the beginning. Compression check.

 

[6car6nage6]

I didnt have a tuner before, and got same size pushrods. I'll check him out thanks. Gonna check compression today and let yall know what I find. Thanks for all the help.

 

[Joshwaa]

Let me know how the compression check turns out. Hopefully he didn't do a valve job and drop the valves further into the head. Cause if that is the case the drop plus the milling your pushrods will be way to long.

 

[6car6nage6]

I will definitely let you know about the compression test. He didnt do a valve job on it, still the same seats and valves. Thanks.

 

[2010 Infantry Vet]

I did get new pushrods, I do need to check compression. It's got stock replacement head gaskets. I didnt get new intake gaskets though, the mechanic said they didnt need to be replaced. As far as timing, I was gonna get cam some point in time in the future when I get more $ up. I talked to a shop that said they do tunes but will be $1,000 to $1,200. After hearing that, I hope it doesnt need a tune. Does anybody in GA know of a place to tune this cheaper? Thanks for all the help guys!

Google barth tuning. He use to be in alphereta GA. A hemifever tune isnt gonna cut it for what he has done. i paid $500 for a dyno tune from Tim Barth. Best way to get a tune.

 

[6car6nage6]

Compression test results:
Cylinder 1 - 180
Cylinder 3 - 180
Cylinder 5 - 0
Cylinder 7 - 185
Cylinder 2 - 170
Cylinder 4 - 180
Cylinder 6 - 180
Cylinder 8 - 183

 

[crackerjack1957]

I hope cylinder 5 is a typo.

 

[6car6nage6]

What do yall think? Tearing it apart tomorrow to see what I can find. I hope my valves are still good. I'm thinking lifters, I shouldve had him change them when the heads were off.

 

[6car6nage6]

Absolutely no compression on cylinder 5

 

[crackerjack1957]

Little more history info on engine, why were heads pulled & resurface, maybe surfaced because they were pulled just for the port & polish?

Probably a bent or stuck valve open on that cylinder.

 

[6car6nage6]

They were taken off because there was a lot of build up on the valves and had a little white smoke coming out of the exhaust(was thinking needed head gaskets and surface the bottom), and thought it was prime time to add a little more HP by porting and polishing.