LML Need some help

cat_dr.

Member
Feb 20, 2013
257
0
16
Jackson,Al
Long story so bare with me. Got 2016 truck that I deleted and tuned with ppei auto cal, exhaust and vas’s lift pump back in 2016 when the truck had 6k miles. Fast forward till a few months ago and guy calls and said he needed head gaskets and wanted to know if I would do it and I was busy and didn’t have time to. So he takes it to another shop the send heads off to be checked replaced gaskets with grade c gaskets and arp studs. Customer gets truck back and complains of low power. Took truck back to shop and they ended up swapping to another tuner adding wc fab y bridge and ic piping. And truck is still low on power. I talked with the guy who did and he has checked compression, check for boost leaks all the normal stuff. Well now the guy brings the truck back to me to see if I can figure it out. Truck runs fine it just lags and doesn’t make near the power it should. So customer wants to swap the turbo and I put a fleece 63 vat o. It. Still same result laggy, slow, and weak. No check engine lights, truck doesn’t smoke or anything noticeable. Any ideas would be great as I’m stumped
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
Long story so bare with me. Got 2016 truck that I deleted and tuned with ppei auto cal, exhaust and vas’s lift pump back in 2016 when the truck had 6k miles. Fast forward till a few months ago and guy calls and said he needed head gaskets and wanted to know if I would do it and I was busy and didn’t have time to. So he takes it to another shop the send heads off to be checked replaced gaskets with grade c gaskets and arp studs. Customer gets truck back and complains of low power. Took truck back to shop and they ended up swapping to another tuner adding wc fab y bridge and ic piping. And truck is still low on power. I talked with the guy who did and he has checked compression, check for boost leaks all the normal stuff. Well now the guy brings the truck back to me to see if I can figure it out. Truck runs fine it just lags and doesn’t make near the power it should. So customer wants to swap the turbo and I put a fleece 63 vat o. It. Still same result laggy, slow, and weak. No check engine lights, truck doesn’t smoke or anything noticeable. Any ideas would be great as I’m stumped

What is the MAF reading at idle? Also, are ALL your temp sensors and pressure sensors reading correct values under normal operation?
 

cat_dr.

Member
Feb 20, 2013
257
0
16
Jackson,Al
I’m sure it’s not the healthiest but I don’t think that’s it. Truck was still running great other than using a little coolant before it got the head gaskets. When driving it the truck will eventually started to make a little power it you hold to it for a few seconds but still nothing like it should be especially with the new turbo
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
I’m sure it’s not the healthiest but I don’t think that’s it. Truck was still running great other than using a little coolant before it got the head gaskets. When driving it the truck will eventually started to make a little power it you hold to it for a few seconds but still nothing like it should be especially with the new turbo

Monitor the post-cac temp sensor, fuel rail temp sensor (on the back of the cp4) and iat2 sensor for a cold to warm run cycle and see what happens. If the truck doesn't have all these sensors due to the delete (because the manufacturer mentioned doesn't account for these sensors in their piping kits, the bungs provided are not the correct thread) then the tuning must be correct to allow the truck to operate properly.
 

cat_dr.

Member
Feb 20, 2013
257
0
16
Jackson,Al
I will check that but the low power complaint started even before the ic piping and y bridge was installed. I didn’t do the retune so I don’t know what info the tuner has but I feel like he knew what was installed and should have tuned accordingly.
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
I will check that but the low power complaint started even before the ic piping and y bridge was installed. I didn’t do the retune so I don’t know what info the tuner has but I feel like he knew what was installed and should have tuned accordingly.

I have had completely stock trucks with faulty sensors and/or wiring on these circuits cause these issues too.
I have also had to argue with the most popular of tuners over this issue because they told their customer that they could not change the tuning to ommit at least 1 of these temp sensors.