Help! Have a 1967 c10 ls1 5.3 swap with; hot cam, 90mm throttle body, 5 speed manual, no cats, short headers with 2.5" exhaust, p59 computer. I just got my HP pro and lm-2 wide band and want to use speed density tuning. Have tried setting up the tune with disabled MAF from "overboost" you tube video, but can't get it to start, just tries and then dies.
fastfredy in Austin area.

 

Did you set the 3 MAF dtc's to fail on first error, then set the MAF fail high to 0hz?

If you removed the MAF altogether you need to wire in a seperate IAT sensor otherwise it will be stuck at -38 and cause you problems.

Post the tune here if you want.

Cable TB or DBW??

 

It wants more fuel.

I ran into a similar issue with my Whipple and SD tuning. Would not start to save my life and Atomic helped me with that. Overall, it wanted about 20% more fuel in the 400-1200rpm ranges.

Once I got it running, I adjusted the VE like normal.

 

Thanks for the help guys but, just tried again after another flash with new SD tune, see attachment. It looks easy to disable MAF, didn't just disconnect it, 1. set MAF calibration to "0" or should I have set MAF fail from 13,500 to "0"? 2. Did the DTC's to 1st fail. I appreciate any help.

tried to upload tune file but won't work?

 

Yes, you still want to set the MAF fail high hz to 0hz because you want it to fail right away.

 

Just tried this flash and motor still won't stay running?
Appreciate you looking at it.
Freddy

 

Can you keep it alive with the throttle?

It may need more/less idle airflow with the addition of the larger throttle body and camshaft.

Can you post a log of it running? Something else could not be working and causing the start/die problem.

 

Thanks for the comeback. Here's the scoop, I have been driving the truck with all of these changes with an original tune that street and performance did several years ago and it ran OK, but wanted to tune it for better performance. They basically set it up with a stock tune out of a 4x4 with a manual tranny but removed the vats. They won't touch anything with a cam in it, so that's why I wanted to do it myself. SOOOO! the stock tune runs OK with all of the changes, cam and 90mm throttle body but I did make some changes for the idle with my new hptuner. The problem is when I modified the tune to SD it stopped running?
Thanks for any help you can provide
Fred,

 

Can you answer my previous question?

How about a log file with as much information in it as possible. Make sure to include all sensors that would want to be scanned.

 

i'm really confused? At this point I will just do a MAF tune and not worry about the SD tune. I think it has something to do with the 2003 computer and the 2003 program from a 4x4 2500 Silverado. this is the computer with the green and blue connectors that was only used that year.
Thanks for putting up with me, and I'll let you know how it goes as soon as I get my AFR cable and do some scans/tunes.
Fastfredy