2015 silverado 1500 lt 5.3L E92 6L80E help

[doobiebanditt]

After adding s&b cold air intake my maf sensor refuses to work I have chased my tail now. I have pacesetter 3in headers catless true duels exhaust as well. It runs on stock tune but choppy like it has a cam don't know if the maf not working has anything to do with it I checked all the wires there fine replaced the maf sensor still fails In vcm suit i get some reading from it but not much. If someone could help much appreciated I'm just lost and need to be pointed in right direction.new idle new maf sensor.hplcurrent tune.hpt

[Ben Charles]

I bet you have a cracked plug..

[kevin87turbot]

After adding s&b cold air intake my maf sensor refuses to work I have chased my tail now. I have pacesetter 3in headers catless true duels exhaust as well. It runs on stock tune but choppy like it has a cam don't know if the maf not working has anything to do with it I checked all the wires there fine replaced the maf sensor still fails In vcm suit i get some reading from it but not much. If someone could help much appreciated I'm just lost and need to be pointed in right direction.new idle new maf sensor.hplcurrent tune.hpt

Looks like you have a couple of issues. The MAF is working, but it's showing very low numbers. You likely installed the MAF backwards.

Problem 2: There's also a big difference in fuel trims from bank to bank. Could be a cracked plug like Ben said, or plug wire that's disconnected...or possibly an exhaust leak. Once you sort out the issue with the MAF, it'll display a misfire DTC if you really do have a misfire.

[doobiebanditt]

Ok I well check maf sensor and check the plugs I have msd wires as well. As far as exhaust leak what would you recommend to use on the pipe I just have clamps on the headers to the pipes

[doobiebanditt]

Looks like you have a couple of issues. The MAF is working, but it's showing very low numbers. You likely installed the MAF backwards.

Problem 2: There's also a big difference in fuel trims from bank to bank. Could be a cracked plug like Ben said, or plug wire that's disconnected...or possibly an exhaust leak. Once you sort out the issue with the MAF, it'll display a misfire DTC if you really do have a misfire.

#4
doobiebanditt doobiebanditt is online now
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Ok I well check maf sensor and check the plugs I have msd wires as well. As far as exhaust leak what would you recommend to use on the pipe I just have clamps on the headers to the pipes

[Tom @ Overdrive]

Ok I well check maf sensor and check the plugs I have msd wires as well. As far as exhaust leak what would you recommend to use on the pipe I just have clamps on the headers to the pipes

It's going to continue to show the "MAF Failed" in the scanner as you have the maf fail tables set accordingly to do so. Put the Airflow Diag tab back to stock.

[TheMechanic]

#4
doobiebanditt doobiebanditt is online now
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Ok I well check maf sensor and check the plugs I have msd wires as well. As far as exhaust leak what would you recommend to use on the pipe I just have clamps on the headers to the pipes

I use a MIG welder to fix exhaust leaks.

[doobiebanditt]

Looks like you have a couple of issues. The MAF is working, but it's showing very low numbers. You likely installed the MAF backwards.

Problem 2: There's also a big difference in fuel trims from bank to bank. Could be a cracked plug like Ben said, or plug wire that's disconnected...or possibly an exhaust leak. Once you sort out the issue with the MAF, it'll display a misfire DTC if you really do have a misfire.

trip 1.hpl here is a long trip cant tell if maf is correct but my ltft are way up some tuner made me the tune on the truck wich is why maf is set to failed. last time i tried to reset values it wouldnt start not sure if it the tune.

[Alvin]

This looks like a solid miss on the driver side.

[doobiebanditt]

This looks like a solid miss on the driver side.

correct i managed to get the maf sensor problem fixed it was on backwards fuel trims leveled out after that too. now my main issue that has me stumped i tried everything i could think of to find the missfire issue in cylinder 5, 7,8 i took spark plugs out switched them around swith wires around , coil packs still same cylinders missfire. im leaning to injectors now but not a 100% sure have any thuaughts on this issue.? it wasnt that bad befor it miss fired but not like this is it possible to be the tune im running.2015 chevy silverado 5.3 stage 1 bolt on catless new tune dtc fixedv2 (1).hpt

[GHuggins]

Does this miss currently happen while driving or just at idle? If it's only doing it while taking off then put your DD back to stock. It's really dialed back and tm will cause misfires via low timing to control torque.

You only have a CAI and headers? Some things in the tune were changed that don't make sense such as your humidity timing modifier table and variable cam ignition timing modifier tables along with your leaned out stoic setting only to add in fuel via the MAF curve, but to each their own I guess.

How many miles are on the motor? If more than 100,000 very well could be injectors. If it's a dead miss or continually getting worse then it's best to do compression checks. DOD issues can cause piston problems, but you would know if you had that. You can however have a lifter or lobe problem.

[doobiebanditt]

Does this miss currently happen while driving or just at idle? If it's only doing it while taking off then put your DD back to stock. It's really dialed back and tm will cause misfires via low timing to control torque.

You only have a CAI and headers? Some things in the tune were changed that don't make sense such as your humidity timing modifier table and variable cam ignition timing modifier tables along with your leaned out stoic setting only to add in fuel via the MAF curve, but to each their own I guess.

How many miles are on the motor? If more than 100,000 very well could be injectors. If it's a dead miss or continually getting worse then it's best to do compression checks. DOD issues can cause piston problems, but you would know if you had that. You can however have a lifter or lobe problem.

it has 88k miles. the missfire has been there for a wile this guy made me this tune when i was having maf issues noticed then had a missfire at idle and drive but it wasnt enugh to throw the light on like today it runniing real choppy give it gas it stoped for a secound then started i dont here a lifter tapping i can flash it back to stock i was just running what a tuner gave to try and help me its frustrating i did the injector kill test in vcm suit when i turned off injector 7 no change weather i turned it on or off when i did it to 5 and 8 it had a change that why i was leaning to injectors but also thaught might be the tune. since i just flashed the new file he gave me once i fixed maf. have header CA smd plugs trans thermostat bypass catless with true duals thats it just bolt ons

[GHuggins]

If nothing else, go back to stock DD tables then yank the drivers valve cover and see if the valve is opening and closing spinning the motor over. Valve train really common and injectors common although haven't seen an injector stuck shut on one of these yet. They usually leak or over fuel.

[doobiebanditt]

If nothing else, go back to stock DD tables then yank the drivers valve cover and see if the valve is opening and closing spinning the motor over. Valve train really common and injectors common although haven't seen an injector stuck shut on one of these yet. They usually leak or over fuel.

this is weird i changed the main tune back to stock just kept cat deleted and dut traction light came on light blinking at me MISSFIRE 5 7 on stock tune just cat off dod off.hpl take a look at this log tell me what you think besides im scrwerd

[GHuggins]

Cylinder 5's the dead miss. Focus on it. Easy enough to crack or foul plugs. Cyl 5 shouldn't be a lifter issue. DOD is 1,7,4 & 6. Cyl 5 is second from rear driver's side. Fix the dead miss then see if the randoms are still there.

[doobiebanditt]

Cylinder 5's the dead miss. Focus on it. Easy enough to crack or foul plugs. Cyl 5 shouldn't be a lifter issue. DOD is 1,7,4 & 6. Cyl 5 is second from rear driver's side. Fix the dead miss then see if the randoms are still there.

Replaced all plugs moved wires around still misfire same cylinder hear tapping noise and traction light on idk what els to do beside tear it down to check lifters

[GHuggins]

Pull the valve cover and check pushrods, valve springs and for valve opening and closing first. Can do in about 5 minutes even having to look for the tools If you hear ticking then probably around that area. Put your hand on the rocker and make sure it's not loose. May be a bent pushrod if it is.

[doobiebanditt]

Pull the valve cover and check pushrods, valve springs and for valve opening and closing first. Can do in about 5 minutes even having to look for the tools If you hear ticking then probably around that area. Put your hand on the rocker and make sure it's not loose. May be a bent pushrod if it is.

have not yet check push but I did run into something confusing I unplugged maff sensor and the misfire stopped was hopping yall could shed some light on this. It an AM maf sensor throws 5 and 7 misfire plugged in I put the oem one back still throws misfire same cylinders. Not sure if is the sensor that bad didn't have this issue tell I fixed the way it was installed backwards have any ideas if I should get a new oem maf sensor first or continue to pursue camshaft dod delete and replace everything lol

[GHuggins]

You need to figure out what's causing the miss. It's not the MAF unless fueling is WAY out. Only reason you're not seeing a miss with it not there is because of dtc and logic operations within the ecm.

Could be something real simple and cheap like a bent pushrod. Verify valve train first. If it's good and good compression then it's the injector.

[doobiebanditt]

You need to figure out what's causing the miss. It's not the MAF unless fueling is WAY out. Only reason you're not seeing a miss with it not there is because of dtc and logic operations within the ecm.

Could be something real simple and cheap like a bent pushrod. Verify valve train first. If it's good and good compression then it's the injector.

Ok I well check it out thank you well update once I further investigate.