slightly modded ABA, rpm drop coming to a stop. please help!

[polski jettski]

Hey guys,
Im looking for a little help with my OBD1 2.0L ABA. I guess ill start with what i have done to the motor.
So its got a 271 degree cam with a tt chip, lighter lifters, adjustible cam gear set to 4 degree advanced. Crankcase breather block off plate, short runner intake with a k&n air filter. Ive got a msd fuel pump and probably a bunch of things that i cant think of off the top of my head. Maintance has been done like plugs, wires, timing belt, fuel filter. The injectors are clean and ive got a new o2 sensor and a new race cat.

So the issue right now that i'm having is when i rev the motor to any rpm and let my foot off the gas the rpms drop down to 500rpm or 600rpm for a second or two then comes back up to a regular idle. Ive had it die on me before coming to a stop when i push in the clutch with my foot off the gas the revs dropped so low that the engine died. Its just a pain in the ass with having to worry if itll stall out at the next stop sign.

Ive had this problem for a while, even before i added some of the goodies under the hood. Any help at all would be greatly appreciated.

Could it be the accumilator pump in the gas tank? Slowing down the fuel before my msd pump? I have higher flowing g60 injectors too but not sure if thatll help at all.

Thanks

[911_fan]

Put the stock injectors back in. You're flooding the engine. You don't need bigger injectors until you start pushing 5+ psi of boost.

[polski jettski]

Ive still got the stock injectors in the car at the moment. I didnt put the g60's in yet, guess their's no need to after all then.
It just feels like it doesnt get enough fuel after you let off the gas quickly.
Would a higher flowing fuel pump be restricted by the stock accumulator pump thats in the tank? Just a idea, wanted to see if someone had any thoughs on that before i go digging into it.
Thanks for the advice

[Anony00GT]

Is your ICV deleted?

[polski jettski]

I still have the wires plugged in but i blocked off the 2 ends on it and relocated it. It wouldnt idle properly when i had it completely removed. And prior to installing the short runner intake i had the ICV all hooked up and still had this issue.

[polski jettski]

I noticed yesterday that it seems to be an intermitent problem.
It seemed fine one minute and then came right back.
Also noticed another issue, when the car is in neutral and i slowly push the gas it will just sputter around 1400 to 1600rpm even once the pedal is pushed half way down. Then it will "snap out of it" and the revs shoot right up to where they are supposed to be. I feel these to issues are linked, happenening at the same time. Any help would be great.
Thanks

[mozcar78]

Things to consider....


1. After Throttle Enrichment.
2. ISV
3. Vaccum leaks.

I would look into those items.


I experience the same thing. Except that I attribute it to not runnig the ISV. It always dips down below 800 rpm when letting off the accelerator but most of the time always comes back after throttle enrichment compensates.

Im running a fully stock setup in my MK1. No VSS hooked up.

[polski jettski]

Thanks for the help i'll look into those things tomorrow and see what i can come up with

[polski jettski]

So after having a look around under the hood and finding no vacuum leaks or any other obvious problems i decided to drill a small hole in the throttle body flap. Figured it might be starved of air and it seemed to do the trick. Runs like a champ now. Should this be alright long term? If not i've got a spare TB just in case i effed this one up.
Thanks for the help guys