P0088, P0191

[Dm23]

Back at it again, looking for some help and guidance.

So I just got home and my truck is throwing these codes. Truck seemed to surge tonight too.

Ever since I had the head gasket job done on my truck p0191 has been present. The dude working on my truck told me the desired and actual aren’t matching via his scan tool. This guy is saying that I need to reach out to the tuner to shut off the code. And it’s because of the way it’s tuned, it’s tuned off the fpr? As you take current off the fpr it’ll cut fuel?

And usually lml’s are tuned off fuel temperature or doing it off the EGR according to him.

It’s a new driver side fuel rail and fpr that was installed not to long ago. Is this something I should log and post up or send the log to the tuner? I have absolutely no idea about tuning or how it works. So I’m reaching out for help. And if I do log it. How the hell do I do that lol

 

[2004LB7]

P0088 fuel pressure too high

P0191 fuel pressure regulator out of calibration

If you replace the regulators with genuine bosch and still get the code then it's your tune

 

[Dm23]

P0088 fuel pressure too high

P0191 fuel pressure regulator out of calibration

If you replace the regulators with genuine bosch and still get the code then it's your tune

Just the one regulator attached to the cp3 right?

 

[Chevy1925]

No, LML have a regulator on the rail and one on the pump. The one on the rail controls the idle and low rpm/power rail pressure. Pump one kicks in above that. There is also a regulator on the return side for return fuel that keeps pressure on injectors to stay above 60psi

If you are running the same tune as before with no codes, this is not a tune issue.

 

[Dm23]

No, LML have a regulator on the rail and one on the pump. The one on the rail controls the idle and low rpm/power rail pressure. Pump one kicks in above that. There is also a regulator on the return side for return fuel that keeps pressure on injectors to stay above 60psi

If you are running the same tune as before with no codes, this is not a tune issue.

Ok. And yes this is the same tune I’ve had for the last 6-7 years with no codes up until recent.

 

[Chevy1925]

Tech needs to do some diag and not try to take the easy way out by pointing fingers.

 

[Dm23]

Tech needs to do some diag and not try to take the easy way out by pointing fingers.

Absolutely. I could tell you more . Just don’t want to put his name/company out there. Shitty part is I don’t know enough to be able to tell this guy any different.

 

[2004LB7]

If it's the same tune then it's either mechanical or electrical. So as James said, tech needs to do their job

 

[Dm23]

So the actual regulator on the cp3 is an lbz because I’m running fleeces PowerFlo 750.

But these are the ones you guys are referring too correct? Before I buy them. Anything else you guys would recommend or add? I don’t plan on taking it back to the guy who did the head gaskets. I have a hard time trusting him, even though that work turned out to be fine.

 

[Chevy1925]

So the actual regulator on the cp3 is an lbz because I’m running fleeces PowerFlo 750.

But these are the ones you guys are referring too correct? Before I buy them. Anything else you guys would recommend or add? I don’t plan on taking it back to the guy who did the head gaskets. I have a hard time trusting him, even though that work turned out to be fine.

So you have a cp3 conversion? Honestly you need to diagnose the issue first before throwing parts at it. You could have a bad connection or no supply power or broke wires

 

[Dm23]

So you have a cp3 conversion? Honestly you need to diagnose the issue first before throwing parts at it. You could have a bad connection or no supply power or broke wires

Yes I do. I agree. Funny thing is. I cleared the codes and drove around today and they didn’t come back on. But last week I did the same thing and the p0191 came back.

I didn’t drive the piss out of it today. I just drove the truck calmly. Nor did I “change” the level on tune today. Just left it at “5”

 

[Ron Nielson]

Those are both circuit codes See the attachments. Intermittent problems are hard to find - just need the right way to get them to act up.

 

[Dm23]

Those are both circuit codes See the attachments. Intermittent problems are hard to find - just need the right way to get them to act up.

Thank you.