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Old 05-23-2006, 05:01 PM   #11
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It'* a new cat.
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Old 05-23-2006, 07:27 PM   #12
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Stupid question here?

Matt do you have a spare MAF, or have you replaced it or swapped it out?

Also if the MAF were reading low, and there was actually more air then the PCM thought there was then the engine would run lean and could cause the Manifolds to be glowing red right?

Just a thought? Am I way off?

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Old 05-23-2006, 07:32 PM   #13
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Quote:
Originally Posted by jdq
What are you gauging it with, I also learned you should be around 0 - plus or minus a few.Maybe you are gauging it differently.
For OBD1 and OBD1.5 cars, 0% is shown as 128. For OBD2 cars it just uses 0%
Quote:
Originally Posted by J Wikoff
There is trim, and there is integrator. Trim should be around 128, integrator should be around 0, if I remember right.
Theres the Block Learn Memory (BLM) or Long Term Fuel Trim and the Integrator (INT) or Short Term Fuel Trim.
Once everything has ben learned,
The LT Fuel trims should be fixed at or close to 128 or 0% while the ST Fuel Trims should hover around 128 or 0%.
The ST Fuel Trim as well as the O2 output will be fixed at WOT.
But yeah. 150 is defintiely an indication of previously running lean up top. The may be too far for the computer to compensate..
The 126 at idle should be close enough to be within facotry spec? Bill?
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Old 05-23-2006, 07:37 PM   #14
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We're dealing with a different animal here. He did the LIM porting (only the ports themselves, not the injector knuckles inside). Port velocity would increase, allowing more air per intake stroke to enter the chambers.

It'* very likely the 3bar regulator can't keep up. His is new, as is his fuel pump. Those were two early steps he took, and both showed signs of age.

At this point, I'd suggest:

1. Get those EM'* good and hot again and make sure they look even in redness/temp.
2. Order the Adjustable FPR.
3. Dial your FP in using the LT and ST fuel trims.
4. When everything looks stable, drop pulleys again.

This is different than mine as I was running a tad lean at the bottom, and far more lean for awhile at the top (overly ported Gen2 TB for some time, but did improve with the Gen3 swap).

It'* risky at this point because the FPR ain't cheap, and it'* not a gaurantee. It worked for me like magic, but I had a totally different (even though it looks very similar) issue.
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Old 05-23-2006, 07:45 PM   #15
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Don't forget to consider gmtuners.
It may take longer but the end result could yeild better LT fuel trims.
It may be cheaper too?
Nobody has done it yet w/ the 93 full on OBD1 pcm so it may take some time to get right.
I do believe it'* in Ryan'* (gm tuners owner) ability though.
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Old 05-23-2006, 07:50 PM   #16
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Quote:
Originally Posted by 95naSTA
Don't forget to consider gmtuners.
It may take longer but the end result could yeild better LT fuel trims.
It may be cheaper too?
Nobody has done it yet w/ the 93 full on OBD1 pcm so it may take some time to get right.
I do believe it'* in Ryan'* (gm tuners owner) ability though.
The Jet PCM has some features Ryan can't provide. In my opinion for those reasons alone, I'd rather stay with the Jet and keep an eye on my FT'* and plugs.

One is a second gear hold, the other is a skipshift. There was something else I don't recall, but John Wikoff has the information.
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Old 05-23-2006, 07:55 PM   #17
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Well depending on wether someone really wants those Jet features it can still be an option.
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Old 05-23-2006, 09:56 PM   #18
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i have had my mind on the adjustable FPR for a while now.
The mainfolds, all 6 ports glow evenly red
ive seen it more than enough times to know lol
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Old 05-23-2006, 10:03 PM   #19
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Also i should mention, even with my new FPR, my pressure is still a few pounds lower than recommended in the FSM, no matter what..
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Old 05-24-2006, 01:10 AM   #20
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Matt, I'm damn tempted to have you test a 2.25bar or 2.5bar regulator instead, but I don't know the difference in fuel demand between your gen2 and my gen3, despite similar LIM porting.

You may just have to bite the bullet on this one. Based on my experience, it won't take much of a bump to get you back in business FP wise.
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