Can't find the leak

[Tazman]

A few days ago I found a leak in the manifold gasket so I had them replaced. Still had issues then found the PCV valve was faulty and it ran great. Then on the way home today while sitting at a light it up and died, started back up by from there on I had to put it into neutral while at a light. With that I thought the MAP sensor was faulty but no code 33 or 34 were present. I have checked all the lines repairing what was needed. This only happens when warm, works fine till then.

Thanks,

[bd]

Check the ignition timing and make sure the distributor clamp is tight.  Spray for vacuum leaks.  Temporarily disconnect and plug the vacuum hose attached to the EGR valve to see whether that makes any difference.

[Irish_Alley]

dont really think the map sensor will cause it to stall
IAC, O2 and TPS will
http://forum.73-87chevytrucks.com/smforum/index.php?topic=29996.0

[Tazman]

What gets me the most is it rarely happens the same way twice. I can be sitting at a light all is well and boom it happens, if I put it in neutral and it runs as smooth as can be. I start it in the morning letting it warm up and all is fine, I go down the road and it acts up. Frustrating is putting it mildly.

[bd]

Disconnect and plug the vacuum hose to the EGR for a few days to see if the symptoms abate.  Don't be concerned if an EGR code sets during that time - it can always be cleared.

[VileZambonie]

Do the test bd said to do. It will take you seconds to do and will easily eliminate this common problem as the culprit or pinpoint it as the source.

[Tazman]

Did it and plugged the hose, went for a short ride. Will know more in a couple days. If the EGR valve is the issue it is inly two weeks old but you never know.

Thanks

[VileZambonie]

The problem is not the EGR valve that you are trying to pinpoint. When you unhook the vacuum source you are not testing the EGR valve, you are testing it's actuation circuit. If it is staying on the EGR will open when it is not supposed to. So if you unhook and your problem vanishes, you know the problem is in that circuit.

[Tazman]

Well it has been a couple days and I knew todays test would tell if plugging the EGR hose would help. In short five mile drives all was well but today I have to go 45 miles and not all was freeway. Right before getting to my destination I noticed it starting to struggle when sitting at lights . I would put in neutral and that would take care of it. Yet one time when I did not it died and it took several seconds to get it restarted. Now back in the garage I plan to look into the connections after it cools down. Will let all know what I learn.

Thanks

[Tazman]

For the peace of mind I thought I would check the timing. So I was getting ready to that when I realized the markings were covered in dirt and gunk. While cleaning my mind woke and thought how can this be this dirty when just three weeks ago the timing had to be reset when the intake manifold had been removed. So I proceeded to check the timing and found it to be way off, I'm talking 8 degrees off. Got it set to where it should and it made a big difference, while out for a drive I stopped by the shop that did the work and asked how did you check and adjust the timing? I was told the guy who worked on my truck was no longer working there, gee I wonder why.

[Irish_Alley]

i wonder if "that guy no longer works here" is what most places tell their customers to make it seam like theyve already taken care of the issue. when in reality the guy is still working there

[Tazman]

Timing is not the main issue. I have another issue which if affecting the timing to the point it moves all over the place when the idle is erratic like it is now. I have taken a video but it is to big for this post. It shows the tach needle bouncing up and down .I have looked for leaks with no luck ,all I have is an injector making a rattle .
I can email the video if anyone wishes to see it.

Thanks,

[VileZambonie]

If your idle is erratic, your timing will be erratic. Start over, describe what's going on now. What symptoms are you having, is everything hooked up working correctly now, just erratic idle?

[Tazman]

When in idle it gets very erratic unless I put it in neutral and is okay. Is good while driving till I come to a stop. I have checked and checked for vacuum leaks but I still think there is one. It is hard to check around the distributor and that end of the manifold. I am thinking of taking it back to the shop that did the gasket install, but I need to find the leak first.

Thanks,

[Tazman]

Tell me, can a torque converter be the cause of this?

Thanks