I need help with a big problem
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Joined: Jan 2014
Posts: 565
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From: 217
Just for fun.... Check your tps w ohm meter. You may have a spot where its not making a good connection through the entire range. Kind of like when a fuel level sending unit starts to fail. It still reads, but not correctly.
Last edited by lsxRanger94; Mar 12, 2014 at 09:24 AM.
.045 would probably be best for a cammed motor. .060 is a bit much and if anything will cause it to miss at WOT. Your fine at WOT because you are in power enrichment and it is using only the MAF (if you have one) for fueling. If your VE table (map sensor) or OLFA (open loop fuel adder) tables is off you'll get all sorts of sputtering.
A dyno tune helps you with getting every last HP out of your motor but not even remotely needed for drivability. A tuner needs to be sitting in the car. Give a good tuner 1-2 hours in the car and it will be smooth.
A dyno tune helps you with getting every last HP out of your motor but not even remotely needed for drivability. A tuner needs to be sitting in the car. Give a good tuner 1-2 hours in the car and it will be smooth.
Where do you live at? Maybe if you PoST that, someone near you can chime in, or may even offer to tune it for you. This stuff of mailing it in every time you make a change could get expensive fast.
Do you know that your MAF is good? Try unplugging it and seeing how it runs?
Any engine codes?
I'm no pro tuner, but its possible your MAF is bad or very dirty and its running well when at WOT while using tables for fueling (OL), but running rough when its using sensors combined with the tables to determine fueling (CL).
Any engine codes?
I'm no pro tuner, but its possible your MAF is bad or very dirty and its running well when at WOT while using tables for fueling (OL), but running rough when its using sensors combined with the tables to determine fueling (CL).
Thread Starter
Launching!
Joined: Jul 2013
Posts: 280
Likes: 1
From: Las Cruces, NM
I live in Las Cruces, NM... and i actually unplugged my maf and it got way worse so its not that....i talked to another ls guy where i live and he said to get a fuel regulator and turn it down to around 50psi instead of having it at 58....
I wouldn't start throwing parts at it just yet. There shouldn't be a reason to drop the fuel pressure, most everyone with big cams is running stock fuel pressure. I am running stock pressure with a large cam.
It sounds like either a bad sensor, a wire short, or just a bad tune.
I'd start by pulling your PCM and ohm out all the wires to the important sensors: MAF, MAP, TPS, Crank, Cam.
Just get a long wire with a paper clip to push into the plugs and use your probe to touch the PCM ports. That's free and will at least eliminate the wiring. Shouldn't take more than an hour.
Are you getting any Knock retard?
If all your wiring is good, not getting any codes for bad sensors, and your not getting false knock from the cam then I would say its a bad tune.
It sounds like either a bad sensor, a wire short, or just a bad tune.
I'd start by pulling your PCM and ohm out all the wires to the important sensors: MAF, MAP, TPS, Crank, Cam.
Just get a long wire with a paper clip to push into the plugs and use your probe to touch the PCM ports. That's free and will at least eliminate the wiring. Shouldn't take more than an hour.
Are you getting any Knock retard?
If all your wiring is good, not getting any codes for bad sensors, and your not getting false knock from the cam then I would say its a bad tune.
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Verdad Gallardo Thread Starter
Launching!
Joined: Jul 2013
Posts: 280
Likes: 1
From: Las Cruces, NM
I wouldn't start throwing parts at it just yet. There shouldn't be a reason to drop the fuel pressure, most everyone with big cams is running stock fuel pressure. I am running stock pressure with a large cam.
It sounds like either a bad sensor, a wire short, or just a bad tune.
I'd start by pulling your PCM and ohm out all the wires to the important sensors: MAF, MAP, TPS, Crank, Cam.
Just get a long wire with a paper clip to push into the plugs and use your probe to touch the PCM ports. That's free and will at least eliminate the wiring. Shouldn't take more than an hour.
Are you getting any Knock retard?
If all your wiring is good, not getting any codes for bad sensors, and your not getting false knock from the cam then I would say its a bad tune.
It sounds like either a bad sensor, a wire short, or just a bad tune.
I'd start by pulling your PCM and ohm out all the wires to the important sensors: MAF, MAP, TPS, Crank, Cam.
Just get a long wire with a paper clip to push into the plugs and use your probe to touch the PCM ports. That's free and will at least eliminate the wiring. Shouldn't take more than an hour.
Are you getting any Knock retard?
If all your wiring is good, not getting any codes for bad sensors, and your not getting false knock from the cam then I would say its a bad tune.
When you remove the MAF and start the motor it should run about the same because it will default to the MAP rather than the hybrid model. If it gets worse when the MAF is removed the sensors are not agreeing or the tune is off. When you tune a motor you will do the MAF or MAP completely independantly. Once you are finished if done correctly you can remove either one and your fuel trims should not move.
It's hard to get it perfect with the MAF as they don't work well at low airflow but you can get it really close.
Once you can verified the wires and swapped out the MAF and MAP with known goods. Don't buy if you don't have to. Just borrow from a friend for an hour. If that doesn't fix it the tune needs to be revised.
It's hard to get it perfect with the MAF as they don't work well at low airflow but you can get it really close.
Once you can verified the wires and swapped out the MAF and MAP with known goods. Don't buy if you don't have to. Just borrow from a friend for an hour. If that doesn't fix it the tune needs to be revised.
Thread Starter
Launching!
Joined: Jul 2013
Posts: 280
Likes: 1
From: Las Cruces, NM
Alright guys, i found the problems well i had my harness custom made and i had the o2 sensors mixed up and i switched em back and its badass i love it now performs badass...thanks everyone!