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Discussion Starter #1
So i got my new Chip yesturday from wester's, I also got new injectors which flow 68lb's. I had the chip tuned to the injectors and for my vortec heads, cam and everything else i had done. BUT IT STILL WONT RUN [email protected][email protected] its ither im not doing something right or i got the WORST luck in the world!!!

Heres whats happening, its really Rich at really low rpms (like 1000), but it wont even idle!, it tries to slow down but wants to stall and then revs right back up!! So i played around with the fuel pressure by lowering it, and it seems to make it a little better by not wanting to stall as much. But i still have a Lean problem when im on the gas, Its also making that Lean Pop noise.

Do i need to adjust the idle set screw to have the butterflys open more for the amount of fuel going in ?? And if i open them up more do i still set the TPS sensors to what ever the voltage is at idle? Everything is at stock still.

When i have the fuel press at 13psi you can really see the injectors flowing fuel!! its accually dripping kinda, when at lower revs.

Anyone got any info that would be great!!
 

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This is exactly why I think the tuner must have the vehicle in front of them on a dyno in order to tune it properly. Send the chip back to him, and tell him what's wrong. He needs to know exactly what fuel pressure you're running though, so don't just start turning the screw on the regulator.

You will always have issues on the bottom end with the cam you chose. The MAP sensor, among others, is going crazy, trying to figure out what's wrong. As I said in your other post, you will always run rich at idle, and lean out on the top with that combo. If you adjust teh fuel pressure for a smooth idle, you're just leaning out the top end even more. If it's low enough that you have a smooth idle, it's dangerously low, and shouldn't be turned past 3000rpms unless you want to rebuild it again.

Do not touch the idle set screw on the TBI base. There is a cover over it for a reason. The idle is controlled by the ECM, and you should not try to tune it yourself when you don't realize the effects of your actions.

Did Lyndon ask for any data that you logged before he burned the chip? He needs this information to set the proper values in your tables. :read:
 

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Discussion Starter #3
91_bowtie said:
This is exactly why I think the tuner must have the vehicle in front of them on a dyno in order to tune it properly. Send the chip back to him, and tell him what's wrong. He needs to know exactly what fuel pressure you're running though, so don't just start turning the screw on the regulator.

You will always have issues on the bottom end with the cam you chose. The MAP sensor, among others, is going crazy, trying to figure out what's wrong. As I said in your other post, you will always run rich at idle, and lean out on the top with that combo. If you adjust teh fuel pressure for a smooth idle, you're just leaning out the top end even more. If it's low enough that you have a smooth idle, it's dangerously low, and shouldn't be turned past 3000rpms unless you want to rebuild it again.

Do not touch the idle set screw on the TBI base. There is a cover over it for a reason. The idle is controlled by the ECM, and you should not try to tune it yourself when you don't realize the effects of your actions.

Did Lyndon ask for any data that you logged before he burned the chip? He needs this information to set the proper values in your tables. :read:
I spoke to lyndon about what was going on, and he told me to take my helix power tower off, and take it for a good drive. Fuel Pressure is locked in at 13psi. I didnt touch the Idle Set screw, not sure what i was thinking at the time, but i know that the computer controls it.
After driving a while it got better, It idles ok as long as im in gear, but every 10 - 20 secs or so, i get a little surge where it revs up a little. according to my scanning software , it jumps into Open Loop for a brief moment as well as spikes the timeing advance. Lyndon told me to disconnect the o2 sensor and see if it still does it. And when i tried it, he still did it!
Now the worst thing is when i touch the gas from being at idle, it hesatates bad, and wants to stall. but then goes fine after that. Kinda disapointed in the power as well. i sure thought it would have more bottom end , and even the top end isnt that great. I wonder if i should change the cam ??!?!

I should be in touch with lyndon tommorow to let him know whats happening now, and im sure he will have a solution. Hopefully we can get it to run good enough to drive daily, and ill take it over to his shop, Hes about 15 hours away. !! =]
 
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