Hesitation/stumble on acceleration

[Mikebtte]

I would recommend a fuel pressure test, fuel pump is a little time consuming to replace so you will need the proper testing. Have you ever replaced your fuel filter?

 

I looked up your wiring diagrams and I do not see a relation to the VSS and the EGR valve. It is possible that your EGR valve could open at idle if the temp and MAP sensor have the proper conditions. 

[Mjricha]

This is so aggrivating. I can't keep testing this stuff right now because the effing truck won't start. I never had any issues with it before except crappy gas mileage and the code 32. Now im like 400 deep in parts and tools and now the truck won't start. I should have just left it alone. 

 

Checked the battery and it's good. Clicks but won't turn over. Starter new as of 4 months ago.

[Mjricha]

Nevermind. Got it started battery was dead. Gonna check the alternator and see if it's toast

[riverbanks]

Storm yesterday,lost cell service,so I hit the books,and internet last night, horror stories about inferior egrs,cts showing temp is up,ecm ready for closed loop,it's starts checking perameters,code 32 is from map and 02,test was performed,bad results, weak egr,not closing quick enough when ecm dropped the signal to the ground at egr solenoid, inferior egr

[Mjricha]

So basically, I need to call gm and get the actual part from the dealer. I've tried 3 egr valves so far and they all do the same thing. They are all Delphi direct replacement part numbers. 

 

Other than that, I'll check all the grounds again.

 

What doesn't make sense to me is that I don't have a code 32 anymore, and that when you said "it's not closing quick enough". It almost seems like it's the exact opposite problem. It's closing from 0to 100% way too fast. As soon as that egr solenoid sends a vacuum the egr is 100% shut. No middle. Just closed. But I'll return these egr valves and get one from gm and go over all the grounds like I said above. I'm assuming it'll be a while before I can get it, so thanks for all your help so far!

[Mikebtte]

Does the EGR valve have a small pin hole in the location were the vacuum hose hooks on? That small pin hole is to restrict how fast the valve fills back up.

[Mjricha]

1 hour ago, Mikebtte said:

Does the EGR valve have a small pin hole in the location were the vacuum hose hooks on? That small pin hole is to restrict how fast the valve fills back up.

No actually it's just an open vacuum line tube. There's nothing in there that would restrict the air flow

[Mikebtte]

The port should have a small hole. If it is large and clear of and restriction the valve will open and close faster than it should.

[Mjricha]

Yes it is definitely the bottom one. I wonder why none of the ones I got so far have the restrictor? Ok that's awesome though at least now I know what to look for when I get a new one. 

[Mikebtte]

Thus is an extra I had in the garage, you can see the port here.

[riverbanks]

Thanks from me also,I had tunnel vision,it can't be the egr,2of em,I guess I stopped looking for the small hole years ago,lol

[Mjricha]

Yes mine definitely does not have that. Would you mind telling me what part number/brand that is? 

[Mikebtte]

Here is all I have. Make sure your current valve does not have that hole further into the stem. I have seen diagrams showing the small hole a little ways in.

[Mjricha]

Thanks for the pic. Googling came up with nothing though. I'll just go to the gm dealer today and show them your pictures and explain what I need. I've looked at tons of different egrs online now and can't see any that have that. Hopefully they'll be able to get this sorted out.