More issues with 87 GN... back again

[turbodiesel6_6]

Well i posted last fall on my GN, and got some good answers... i did a little cleanup on the car with some mods, and im still having lots of issues, hopefully someone can direct me. Im gonna attach two scan logs, one is ideling warm, the other is driving down the road. You will notice in the scan that its showing batt. volts low... but when i check the batt. with a digital gauge 13.50v. The issues im having is the engine feels like it miss fires. When i installed the TT chip, i drove it for about 45 mins. before i got on it. Got on it the first time, about 12 to 13 psi of boost, and had a back fire, from what sounds like it cam through the intake side. So after reading some posts, double checked my rail pressure, and its set at 43psi w/vaccum line off, 38psi w/line on. Put R43TS plugs in, gapped at .035. New plug wires. Another issue im having is i drove the car today for about an hr without getting on it real hard, and when i was on my way home, the car felt like it was bucking... shifting to early.. or just lack there of power... maybe converter not locking up... feels like some major slip to me... but hopefully its engine related. Any more info. that you may need i will be happy to answer to the best of my ability lol.... hopefully the scan will help....Thank you in advance!!!!!

 

[ES1]

I have seen post the the SM battery readings are on the low side.
You MAF reads OK at idle but whenever there is a problem like you describe, I always check the MAF.
The only other thing i saw is you appear to be running on the rich side, blm in the 115 but that is still within correction of the computer.

 

[turbodiesel6_6]

so are you thinking o2 sensor maybe? Fuel pressure to high? I was curious if it wasnt the coil packs causing the backfire under boost... as with the running rough. When driving down the road it sometimes feels like it is cutting out. Then at other times feels as if the transmission cannot make up its mind...

 

[ES1]

Look at your MAF numbers while driving.
They drop down to 9 @ 60mph.
My guess is your MAF.
A bad MAF can cause all kinds of issues.

 

[turbodiesel6_6]

I will try a MAF, i wanna do a translator, i checked out full throttle speed, and im on the fence with the MAFs, and i would need a tube... but heard horror stories of the tubes not fitting right... guess im not sure of what i need... whats the diffremce between the LS1 and the Impala MAF?

 

[ES1]

The 2 most used are the LS1 & LT1 MAF.
One is a 3in & the other is 3.5.
The 3.5 is supposed to have better response but I run the 3in with no problems.