I just did a porting job on my intake upper and lower and runners, added a FPR and a throttle body foil, plugs, wires, cap and rotor.

Issues
1.) I've been having a problem with Ideling i get a little hesitation.
2.) Start up cranks over a few times then it starts and is weak then it picks up after gasing up.
3.) Insterment panel claims i'm only getting 15MPG


Tested
1.) Fuel pressure Holds soild for 20 mins when car is off and key out. then slowly slowly bleeds down. Fuel Pressure WOT 49 PSI and Idles at 38PSI Injectors seem good maybe bad 9th injector i'm thinking
2.) Car takes longer to start when opening throttle.

2.) I pulled out my spark plugs all of them looked like they've been straving for fuel. White flaky stuff on them.

What I think might be bad is the O2 sensor. Maybe coolant hit my O2 Sensor after doing the intake job.

But will a O2 sensor, cause a lean start?
Will a O2 Sensor tell my ECM it's running very rich and to lean out?
Will then the Computer tell my Insterment panel you are running rich and show the it is using to much gas?
Or maybe it's a vaccum leak i can't hear any leaks i also sprayed gum cutter around nothing idle changes


If all Yes then i need a O2 sensor right? Also I went into my BPW fuel range on my chip and bumped everything up .40 and the car ran much better. Maybe thats all i need to do is just bump up my Fuel more across the boards. Maybe after this intake port job it's pulling in way to much air not enough fuel? FYI car runner very very well just those couple issues Anything well help.

 

A weakening O² sensor typically generates a lower and lower signal, which the ECM interprets as a lean condition. It will them try to enrich the mixture to compensate. That's just opposite of your idea.

Additionally, the O² is not involved in startup fuel trims, and does not become active until after a coolant temperature threshold and timer are satisfied. All the startup fuel is in the programming. If your 9th injector is leaking, that would tend to create a rich condition, not lean.

Your standing and running fuel pressure appear to be good.

If yuo have a digital dash and mileage display, the ECM measures and tallies total injector pulse time (fuel used) and compares it to VSS pulses (measured distance) to arrive at a MPG calculation. The oxygen sensor can only tell the ECM to administer more fuel to satisfy the sensor. There is no direct relationship between the O² and MPG display.

What fuel system are you using? MAF or S/D? If you have an S/D system, the MAP may have changed as a result of your work, and the VE tables may need some tweaking.

 

While coolant will readily kill on O2, I'd take a quick look at your IAC before diving anywhere else... at least for the startup and idle issues.

 

I think i found my problem! Well I replaced the O2 (only $20) before i read this post. Some fool that I talked to said the O2 senor reads in open loop, I kinda new that it only reads in Closed. That makes total sense.

I have MAP setup, i went in and changed my values for MAP settings which didn't help much. My IAC I'll check very soon. I did bump up my fuel and WOW it pulls even harder.

PROBLEM: The little edmissions tube that runs from the header to the Intake on the Passanger side seems to be leaking. It's hard to tell feeding that area gum cutter but i'd say thats my best beat because my gaskets look like they are seeeping out i think i might have over toqured that tube. it's hard to test that area with gum cutter for vacumm leaks. I guess because exhaust is pushing into the intake and the intake is sucking air from the exhaust. that would explain why it starts up like crap i think. Right? I'll also check my IAC tonight.

 

PROBLEM:
1.) I'm still running lean on Cold startup only it seems.


REPAIR:
1.) Well I cleaned and My IAC and bumpped up the steps in my prom a little just to test things out. Seems to work great. I think i ruled out IAC.

2.) Edmissions tube replaced with new and new gaskets. Then tested again for vaccum leaks. Can't find any at all anywhere. i ruled that out.

3.) Bumpped up My BPW total 2.40 so like 25% Seemed to help on start up a little more. Also driving preformance is a plus too. Seems to like more fuel this bad boy gets to pulling harder each bump up of fuel i give it.



COULD IT BE:
I think this all might have to do with a good chip burn, I think all my work looks good. I took my time everwhere when i ported out upper lower and runners and all. I trust my work for the most part.

Question: My PROM is functioning right off the bat on start up. right? I mean PROM is alway running it just doesn't run in closed loop only. right? Reason i think it's this thing is becasue i did kinda hog out my parts and the car seems like it's liking the extra fuel it gets. Maybe i can insert my stock chip see if there are any changes anywhere? Guess if it takes longer to start cold i'll know i need to make so mods in my chip. I'll need to move into the PROM tech board and get help there.



MODs: I removed the coolant hoses from my throttle body just for the hell of it yesterday. All ready there so i just did it.