Hesitation/stumble on acceleration

[riverbanks]

Ok, right? you have one unknown reading, fuel pressure,if high,rich,ecm can't compansate enough to correct, your temp should come up too,lean is hotter,and the map should drop a bit

[Mikebtte]

I had to start over and read your fisrt post again. Are you still having the issue with the black smoke? If your still getting the black smoke it could very well be a fuel pressure relate issue.

Do you have aftermarket exhaust? Some people have had to change to a heated O2 sensor when they change it. I have had no issues with 1 wire on my exhaust.

[Mjricha]

7 minutes ago, Mikebtte said:

I had to start over and read your fisrt post again. Are you still having the issue with the black smoke? If your still getting the black smoke it could very well be a fuel pressure relate issue.

Do you have aftermarket exhaust? Some people have had to change to a heated O2 sensor when they change it. I have had no issues with 1 wire on my exhaust.

No I don't. Just the one that came on the truck when I bought it. When I got I under the truck there was a good sized dent in the muffler but it doesn't have any brand names on it. I looked up the stock exhaust and they look similar. 

 

And yes I have the black smoke still. 

I really don't want to buy a fuel pressure gauge too lol. Between the mtimeter the vacuum tester and the aldl cable I'm up to like 200 dollars now. Is there a way to do it other than buy the tester and cut the fuel lines, flare them, and I still the tee for the fuel pressure? Mine doesn't have a test port on the tbi

[Mjricha]

What would cause the fuel pressure to be too high anyway? Too low I understand, but I can't think of anything that would increase fuel pressure other than the regulator which is brand new. 

[riverbanks]

Not all are equal, restricted will raise it,so, another test,hold throttle at 2k rpm,up to temp. does 02 fluctuate?or still high?more air helps level out a rich condition,and do it with egr intact and vacuum line to it plugged, check for different readings

[Mjricha]

3 hours ago, riverbanks said:

The longer it ran,the richer it got,02 stopped going below .45,I'm thinking faulty fuel pressure regulator,you could introduce a vacuum leak, like have brake booster hose just connected,then pull it off a little and watch 02 reading,see if it follows, dropping,that tells you it's not loosing its ability to follow

So I ran this test,

 

02 readings started bouncing around, going from around 300 to upper 500mv. 

 

Map raised to 36-37 from 32. 

[riverbanks]

So that test would show that down low on rpms there is excess fuel,at 2k rpms there is less flow needed thru return line,cause the motor is using more,so the sensitivity on regulator is comprised,and shame on them for no test port on tbi's

[Mjricha]

27 minutes ago, riverbanks said:

Not all are equal, restricted will raise it,so, another test,hold throttle at 2k rpm,up to temp. does 02 fluctuate?or still high?more air helps level out a rich condition,and do it with egr intact and vacuum line to it plugged, check for different readings

Ran this test also:

With vacuum to egr intact:

Raises to around 700, but fluctuates between 500 and 700. When I let off the gas it spikes to about 800 and then slowly drops to bouncing between 300 and 500. 

 

With vacuum line to egr plugged:

Basically the same thing, only the truck isnt wanting to die the whole time. 

 

[Mjricha]

So here's a dumb question. I'm not being sarcastic, but how is this related to the EGR valve kicking in at low rpm and trying to kill the truck? 

Is it because there is excess fuel so the ecm thinks the truck is at a higher speed or something? 

[riverbanks]

It's a reaction to a bad action elsewhere,so we are narrowing down the fault,can you post another scan at 2k rpms?

[riverbanks]

And that's why you got a cel,there is a conflict of data to ecm,so it throws a flag

[Mjricha]

Well there is no Cel light anymore, after I switched out the egr it went away, and I got this new problem that we are working on now. But here are the two new videos

 

 

 

Sorry it might be hard to see its very bright out today

[riverbanks]

My browser does not currently recognize any of the video formats available,that's what I just got,what a joke,I'll try again in a few

[Mjricha]

Really? That's weird they're just on YouTube. 

[riverbanks]

Storm,? I'm in the sticks in upstate n.y.,we just got sliced bread last year,oh,what a party,I'll try again