MAF Mod followup
#15
Senior Member
Posts like a Camaro
Join Date: Oct 2003
Location: Hamilton, Ontario
Posts: 1,074
Likes: 0
Received 0 Likes
on
0 Posts
Sorry, is this about the removal of the little brace inside the TB? It has the MAF in it right? Could you possibly link the old thread to this one?
#16
Senior Member
True Car Nut
Thread Starter
Join Date: Nov 2002
Location: Texarkana, Texas
Posts: 6,042
Likes: 0
Received 0 Likes
on
0 Posts
We started out in this thread: http://www.bonnevilleclub.com/forum/...ic.php?t=24243
PDad, From I can tell with limited experience and DrJay can tell from the numbers and what I'm saying, It'* probably a fuel delivery problem. The car idles perfectly, It can handle a quick rev, But when under load at WOT it bogs like no tommorrow. This isn't connected to the mod as it'* gradually been getting worse at doing it, I just didn't know it and didn't have a scantool to check it.
I'm a couple hours from putting the TB back on, Then I'll get a Fuel Pressure Guage and we'll see whats up. This thing is scary powerful sounding, Hopefully it'll be as fast as it sounds.
PDad, From I can tell with limited experience and DrJay can tell from the numbers and what I'm saying, It'* probably a fuel delivery problem. The car idles perfectly, It can handle a quick rev, But when under load at WOT it bogs like no tommorrow. This isn't connected to the mod as it'* gradually been getting worse at doing it, I just didn't know it and didn't have a scantool to check it.
I'm a couple hours from putting the TB back on, Then I'll get a Fuel Pressure Guage and we'll see whats up. This thing is scary powerful sounding, Hopefully it'll be as fast as it sounds.
#17
Junior Member
Posts like a Ricer Type-R
Dame, I just got off the phone with Pdad. We were discussing your KR. I think your loose rockers were causing most of it, falseley. Try another run after you get them all re-torqued, and try to duplicate conditions.
Your loose rockers were in the rear bank, which is closer to the knock sensor than the front. Loose rockers are VERY big contributors to false knock.
Your loose rockers were in the rear bank, which is closer to the knock sensor than the front. Loose rockers are VERY big contributors to false knock.
#18
Senior Member
True Car Nut
Thread Starter
Join Date: Nov 2002
Location: Texarkana, Texas
Posts: 6,042
Likes: 0
Received 0 Likes
on
0 Posts
All rockers are retorqued.
I got fuel pressures of about 30 at idle, on WOT snap it jumps to about 40 then slowly goes down with the rpms to about 38 at redline.
I just got a run in the scantool, I'm Going to upload it as soon as I get it in the pc here in a minute. It'* still doing the same thing...
I got fuel pressures of about 30 at idle, on WOT snap it jumps to about 40 then slowly goes down with the rpms to about 38 at redline.
I just got a run in the scantool, I'm Going to upload it as soon as I get it in the pc here in a minute. It'* still doing the same thing...
#19
Senior Member
Certified GM nut
Join Date: Feb 2003
Location: Georgia
Posts: 2,095
Likes: 0
Received 0 Likes
on
0 Posts
Yup, I'd say you prrooobably found your problem..
Next while letting the engine idle pull the vacuum line off the FRP and note what the difference in pressure is.
I've been working with him on this issue for a little while now. I was thinking possibly false knock but after looking at his fuel trim I started to rule that out. Between the one he posted and others of his he'* shown me his trim level is really jittery, and usually high. Since sometimes pumps will work-kinda work-work-kinda work it would match up to his bouncy trim levels. That coupled with the fact that the pcm retarding the timing was not seeming to help (KR actually growing as he accelerated) kept me believing it was a fuel issue.
In anycase dame - get that '94 one in there!
Next while letting the engine idle pull the vacuum line off the FRP and note what the difference in pressure is.
I've been working with him on this issue for a little while now. I was thinking possibly false knock but after looking at his fuel trim I started to rule that out. Between the one he posted and others of his he'* shown me his trim level is really jittery, and usually high. Since sometimes pumps will work-kinda work-work-kinda work it would match up to his bouncy trim levels. That coupled with the fact that the pcm retarding the timing was not seeming to help (KR actually growing as he accelerated) kept me believing it was a fuel issue.
In anycase dame - get that '94 one in there!
#20
Senior Member
True Car Nut
Join Date: Jun 2003
Location: Purgatory
Posts: 6,313
Likes: 0
Received 0 Likes
on
0 Posts
The fuel pump crapping out would cause the car to run lean and create kr so that makes sense. What is the lean condition doing to your plugs? You might want to recheck the gap?