TwitchZ28

iTrader: (3)

I added a 228R cam on 112 LSA to my 2002 Z28 a few months back, and it's been having issues.

The car is an auto, and has a ptc 3200 converter.


So here is what it's doing. After the cam install and initial tuning the car was having really big problems stalling out at low speeds. If I was sitting in stop and go traffic and hit the gas to move then got back on the brakes the rpms would fluctuate significantly then it would stall. It's only an issue is 1st gear and reverse gear.

Reverse is the worst...sometimes just letting off the brakes and getting back on them to shift into forward gear is enough to kill it.

So having these problems I contacted my tuner and we met up. He spent a few hours fine tuning the idle fuel tables and such and by the time we went our separate ways the car was driving PERFECT. I couldn't stall it if I tried.

It was great...for about a week.

Then it started slowly reverting to it's old tricks and now it's completely back to being a PITA the try and drive around town.

If I reset the idle air control the issue goes away very temporarily, but it always comes back. I am thinking at this point I may have a hardware issue or something. Can anyone please give me some advice on where to go from here. I can't be driving 2 hours to meet my tuner every 2 weeks to redo this ****.

Remnant-of-VII

Sounds like a tuning issue. May have to do with your Throttle Cracker table not adding enough air while your rolling to a stop. (Throttle Cracker adds air to desired airflow via IAC while in gear.)

Just need to get your tuner to bump up the airflow a bit at a time on the throttle cracker table around where the engine would start to stall out.

NicD

iTrader: (7)

A 228 is not a large enough of a cam to be having the common problems with stalling and aftermarket torque converters. The one thing you can be sure of is that the tune itself doesn't change and if it was PERFECT for a week after it was tuned something else may be the matter now mechanically speaking. Without looking at the tune and logs it's really impossible to tell what may be causing it and everything anybody posts online without that or seeing it in person is speculating.

wait4me

iTrader: (10)

Unplug the battery for a minute and then plug it back in and see if it runs good again. If it doesn't, then it is tune related. If it does get better, then there is a sensor causing you issues I would guess. But you need to pull the battery. That flushes the learnt data in the 4000-8000 in the computer so it goes back to all the hard setting in the tune.

TwitchZ28

iTrader: (3)

I'll give this a shot and check back.

I've done this before, but only to turn of the CEL after resetting the tps. It's made it improve.

I'm guessing it's the tune but if it's the tune...why was it good for a while and now not? Seems puzzling.

zrultima

I have the same exact issue with the same cam and everytging

SMOKINV8

iTrader: (6)

What throttle body are you running? I had a car with that cam giving me fits for a while, which is ridiculous. My gut tells me we worked around a mechanical issue, but it related to his aftermarket throttle body.

TwitchZ28

iTrader: (3)

Stock TB.

Has to be in the tune because it stops screwing up when the battery is unplugged for a bit.