First scan after build
#11
Senior Member
Posts like a Corvette
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
I pretty much agree with what'* been said already.
Your trims and IPW'* say that your PCM thinks your air and fuel are properly balanced, however, your O2 voltage values say you're mega-lean. (0.850-0.880 is what I shoot for...cammed, you may want to aim slightly higher, like 0.870-0.900)
You are getting way lower MAF values (I assume the units are g/sec) than you should be, I think. I wonder if you can get your hands on a known good MAF sensor to swap in, just to rule out a bad MAF?
From the looks of things, either you're getting alot of unmetered air (massive vacuum leak) or alot less fuel than your PCM thinks (blocked filter/line, low fuel pressure/weak pump).
Your trims and IPW'* say that your PCM thinks your air and fuel are properly balanced, however, your O2 voltage values say you're mega-lean. (0.850-0.880 is what I shoot for...cammed, you may want to aim slightly higher, like 0.870-0.900)
You are getting way lower MAF values (I assume the units are g/sec) than you should be, I think. I wonder if you can get your hands on a known good MAF sensor to swap in, just to rule out a bad MAF?
From the looks of things, either you're getting alot of unmetered air (massive vacuum leak) or alot less fuel than your PCM thinks (blocked filter/line, low fuel pressure/weak pump).
#12
Senior Member
Certified GM nut
Thread Starter
Join Date: Dec 2002
Location: plattsburgh NY
Posts: 2,037
Likes: 0
Received 0 Likes
on
0 Posts
Just talked to zommer, he agrees 100% low fuel pressure (more then likely due to old pump). Just talked to a company about a high flow 255, and looks like that will be ordered very soon along with a new filter. Then we will go from there. I agree with everything you said Andrew (pm me with some tuning ideas, for when i get this thing running decent)
#15
DINOSAURUS BOOSTUS
Expert Gearhead
Originally Posted by 95naSTA
I would go stock replacement for the fuel pump. There is no reason to get a high flow one.
#16
Senior Member
Certified GM nut
Thread Starter
Join Date: Dec 2002
Location: plattsburgh NY
Posts: 2,037
Likes: 0
Received 0 Likes
on
0 Posts
yea for the price, truthfully i can not, not get the high flow. I mean for an extra 20 dollars i would rather pay it just for piece of mind.
#17
Senior Member
True Car Nut
Join Date: Feb 2003
Location: Philly
Posts: 4,508
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by BillBoost37
Originally Posted by 95naSTA
I would go stock replacement for the fuel pump. There is no reason to get a high flow one.
He could still bump up the fuel pressure with an adjustable regulator on a stock pump. I can't imagine you would NEED to upgrade the pump to see the fuel pressure needed to take advantage of better atomization.
Why go overkill and add another variable into the mix if you don't have to?
#18
DINOSAURUS BOOSTUS
Expert Gearhead
With a stock regulator there is no additional variable. If he needs to add it he can.
It'* interesting that you are countering each thing this much Mike. This weekend TJ was worried that his car would even run with that cam because of your advice to him. We literally had to get it running before he would believe that he wouldn't require a different pcm eprom to run.
It'* interesting that you are countering each thing this much Mike. This weekend TJ was worried that his car would even run with that cam because of your advice to him. We literally had to get it running before he would believe that he wouldn't require a different pcm eprom to run.
#19
Senior Member
True Car Nut
Join Date: Feb 2003
Location: Philly
Posts: 4,508
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by BillBoost37
With a stock regulator there is no additional variable. If he needs to add it he can.
It'* interesting that you are countering each thing this much Mike. This weekend TJ was worried that his car would even run with that cam because of your advice to him. We literally had to get it running before he would believe that he wouldn't require a different pcm eprom to run.
It'* interesting that you are countering each thing this much Mike. This weekend TJ was worried that his car would even run with that cam because of your advice to him. We literally had to get it running before he would believe that he wouldn't require a different pcm eprom to run.
I never said my car didn't run. It started to run crappy when it heated up. My car ran a whole lot better when I started to tune.
When ever I talked to TJ, all I ever talked about was getting a scan tool, getting comfortable with it, and get ready to tune right away. That is the single most thing I wish I had done differently.
I have been telling him to get that cam for years. I suggested ERs, 105'*, and various other things but I guess that'* bad advice too huh?
That stock pump had how many miles on it? I would rather put a stock pump in just for that reason. What'* the highest mileage on a Walbro?