angcobra

After reading some of the other posts, I may have mis-spoke on this, I assumed youused additiveto engine oil, but instead you may have been talking about adding to fuel. Sorry I might have been on the wrong page.
If you added it to the fuel, it most likely is related. Any concentrated cleaner added to fuel could cause partial clogging of injectors which will impact the spray pattern thus impacting performance.

wasvette

I'm getting more confused with this by the day but I do really appreciate everyone's input.

After driving for a few days, here's what I know for sure:
[ul][*]Hesitation is almost random - when it happens, the car falls on its face between literally 1800 RPMs and 3000 RPMs.[*]Runs perfectly 1st thing in the morning and for an hour or so - I can get on the interstate after the car has been running for 5 - 10 minutes and it screams with 0 issues.[*]Worst hesitation occurs after parking for a sales call and then coming out 20 - 30 minutes later. Seems like a "heat" related problem -are fuel pump issues sensitive to heat?[*]It has 81,000 miles - should the spark plugs be replaced anyway due to mileage?[*]There is a TSB on the fuel pump and I used to have the classic issue described after cruising - so should this not be replaced anyway?[*]Could some of the causes of my problem been there the whole time but now be pronounced due to the extra fuel/spark demands of the Steeda CAI and SCT 93 Tune.[*]Would returning it to stock definitively prove anything if the problem is what I said in the previous bullet point?[*]Final Point - I have never spent so much time trying to get a $700 mod to actually work as intended.[/ul]
Thanks!
Kevin

Mikes_BLK_GT

1) Shouldnt take long to return to stock to see of that is indeed the problem. If it is you will stop seeing the hesitation, if its not you wont.

2) If theres a TSB and you havnt had it done I would get the fuel pump taken care of and go from there.

Do those 2 things first and you'll be ahead of the game, your out of warranty so I guess that wont help but I dont believe it's your spark plugs otherwise you'd see the issue be more consistent I would think.

moosestang

No ****!! that's some BS IMHO. Did your miss in your work truck cause a vibration? I have a vibration at 3200, most noticeable in 3rd and 4th. I was going to try and buy 1 spark plug and injector froma FI guy on here. That way i could swap them out 1 at a time and see if it solves my problem.

moosestang

81k on stock plugs? I would change those for sure. At the very least I would pull them and check them.

hammeron

recommendations:

1) return car to stock airbox and tune

(*)
did this correct problem
yes > all is well
no > proceed to next step

2) clean or replace fuel filter

*

3)
clean fuel injectors (i don't know how this is done)

*


4) remove spark plugs, clean if possible, check gap, reinstall

*

-------------------------------------------------------------
that's as far as i can take you, the dealership may be the next
option.


good luck and everything's gonna be fine

05 Ricky

Yes it caused a vibration and a studder and once I was at higher rpms it cleaned up[&:]Vibrations can be cuased by way to many things[8D]

wasvette

I truly appreciate everyone's blood, sweat, and tears on this one.

UPDATE: Absolutely HEAT related, period. As long as the car is moving and air is flowing through the engine compartment and enhancing the cooling effect ALL is good....Stop and park for 10 minutes and let the heat soak begin. Not sure what's "heating up" but something changes. Drive for 5 minutes over 50 mph and all is good again.
Ditched the throttle body spacer tonight just to simplify what's going on. Re-tuned with lower fan turn on temps. Drove and ran liked a scalded dog. Didn't park and turn off and then run again...will see tomorrow.

Regardless, will swap all plugs and fuel pump. However I believe the CAI (and install of) and Tune is fine.

Thanks Guys!
Kevin

wasvette

For those that were following this thread.......the fuel pumphas beenswapped under warranty by a dealer here in Atlanta......problem still exists, though not as bad. IT ONLY HESITATES UNDER MODERATE TO HARD ACCELERATION WHEN IT HAS SAT PARKED FOR A FEW MINUTES AFTER DRIVING....HEAT SOAK....LET IT RETURN TO NORMAL TEMP WHILE DRIVING AND IT RUNS PERFECTLY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

.....WHAT IS HEATING UP? IS THE MILLION DOLLAR QUESTION....DID NOT DO THIS PRE-CAI AND TUNE...

DUMBFOUNDED IN GEORGIA.....

moosestang

Did you ever remove the CAI and tune? Common sense would tell you that's the problem if the problem started right afterwards.