Check out my dyno charts for a comparison as to what's going on. Thought I would finally post the chart showing how rich it became.

 

Sound kind of like when my EGR valve went bad on me of all things. I grabbed a scanmaster and one of my banks was either rich or lean, I can't remember, but one side was different than the other and it was due to a bad EGR valve. Doesn't make sense, but it solved it. I was getting an intermittent SES light though too.

GM even had a service bulliten out about it I believe.

Might be worth checking.

Dan


:EDIT:, Oops, just read that you already changed it. You might just want to double check the connections and if it is sealed well though.

 

Yeah, I retorqued the bolts when I had the fuel rails off of it. It's sealed pretty well back there. I was having a slight split LTerms problem when I would put the injector constant to something outrageous like 35 LB/Hr, but I solved that by doing the IAC passage on aftermarket TB's mod. You know, the copper pipe thingy.

Like my techinical jargon??

 

I know this is a long shot but have you replaced all the injector seals?

Mine was having a low vacum at idle. right around 16 HG of intake vacum. I replaced all the seals and now it holds at 20HG of intake vacum. I have never tuned my PCM. and I did notice very little difference after the swap over but the Vacum defenetely improved. Could you be having a vacum leak at one of them and the PCM is dumping loads of fuel??

Its a long shot but you never know.


Marvin

 

Oh I forgot. Disconec the vacum hose that goes to your Evap Canister. Plug the conection on the Passenger side on the TB. and see if the car gets better.

I read in the chiltons book if one of those valves to the Canister remains open it will allow fuel fumes into the manifold making the car run very rich. It does go say that you will be able to smell the gas around the TB i recall.


Marvin

 

The EVAP Canister Purge Solenoid was my last Hurrah. I took it in after checking that. I was extremely hopeful when checking that though.

The problem is though, with my issue, it's not the computer dumping the fuel in. With the LTerms showing 108, that's telling me that the computer is reading it rich and it taking fuel out.

 

Well, FBC was all over it yesterday. Logging, scanning, ect. There is now starting to be a split LTerm condition, and the Base pulse width on the injectors is split too, 1.9 ms and 3.6 ms.

We did some discussion last night, and it's starting to point more and more towards a vacuum leak that's opening up with the car warming up.

More to follow. They're searching for a leak now AFAIK.

 

Did you ever chack to make sure your throttle body blades were closing all the way? Like adjust the stop screw? So the BLMS stay down.. Mine was hesitating, its fixed, that was my problem.. Its always something simple in the end and you just over looked it so im just throwin it out there..

 

Yeah, that was part of me adjusting the IAC counts. Just got off the phone with Jeff, and it's sounding like they're as stumped as me on this now.

Is it possible to have an internal vacuum leak somehow???

Must be a black car thing.

 

????

 

forget FBC!

Time to take it to the Exorcist!

 

I'm gonna be taking a lifeless frame to the morgue if this crap keeps going on.

 

Kill it ! Ya Ya Kill it !!!

 

 

i found my felpro header gaskets were leaking........not really bad enough to hear over the exhaust........but bad enough to affect performance and O2 readings.

i doubt its your problem, but for everyone out there, it doesnt hurt to check!