2.0L 16v losing power when stereo cranked up

[1SlyGTI]

I have a 92' GLI 2.0L 16v (CIS-E / Motronic?) setup.

I've redone all grounds with 4g wire, using a yellow top optima battery and a custom 200A alternator from Excessive Amperage. I'm pushing about 3800W RMS to a pair of subs and mids/highs.

Voltage holds strong at 14.7v regardless of what I turn on, or how loud I crank it, but my idle starts "stoopering" and "sputtering" after a very short time (30-60sec).

I'm at a loss here. I've got a new Idle Control Valve on the way in hopes that perhaps it's just my idle valve, however; I notice it will also affect engine power at driving speeds (any). If I crank it up the engine will start losing power and sputtering.

I'm considering a new coil now, as well, but I wanted to ask in the only community I trust... Do any of you guys have any suggestions?

[kompressorgolf]

are you using stereo power wire from the alternator to the battery>? may not be carrying enough amps of so.
used 4 gauge wire front to back to my battery (trunk mounted) and had issues, switched to heavy copper battery
cable and is fine now, just a though, good luck

[1SlyGTI]

Yes, I'm using 4g solid copper power wire for both power and ground (Big 3).
All amp wire is 8g -

I went to install the AutoTech Power Module today and coincidentally my coil went out.
Now I'm left wondering which coil I should replace it with...

It's currently/was using a typical bosch coil, but I'm finding that the recommended ignition
coil is actually a different setup and has some sort of "booster" attached...

[perrib]

Check for a voltage drop on the ground side.

[cuppie]

I went to install the AutoTech Power Module today and coincidentally my coil went out.
Now I'm left wondering which coil I should replace it with...

It's currently/was using a typical bosch coil, but I'm finding that the recommended ignition
coil is actually a different setup and has some sort of "booster" attached...

FYI: the Power Module is not for KE-Motronic cars - they're 'chippable.'
Power Module is only for KE-Jetronic cars.

And, that "booster" on the coil? That's the output stage between the Motronic box and ignition coil.
On Motronic, it serves to relieve the ECU of the currrent load (and heat) of controlling the coil.

[1SlyGTI]

FYI: the Power Module is not for KE-Motronic cars - they're 'chippable.'
Power Module is only for KE-Jetronic cars.

And, that "booster" on the coil? That's the output stage between the Motronic box and ignition coil.
On Motronic, it serves to relieve the ECU of the currrent load (and heat) of controlling the coil.

Well, then forgive me for the confusion. There are a couple of things I'm learning here.
1.) I was told the engine was 2.0L 16v out of a 92' GLI - Yet I've now found it's running a 1.8L
coil and ISV. (I know this because I just dropped 260 bucks on an ISV for a 2.0 and it's
bigger than the one currently on the engine. (The 2.0 16v ISV is a larger diameter).

2.) It is a KE-Jetronic injection system. (The fuel lines run from injectors to air box on pas. side).
I was told this by a friend whom is a certified Euro tech. I just get the two mixed up all the
time.

I'm wondering if it is, in fact, a 2.0L but whoever did the swap wired it up with the stock 1.8L 16v (that was in it originally because it's an 88 GLI) Coil and ISV? Would this help explain why she doesn't like to hit 6,000+ RPM (doesn't pull past that point and likes to sputter from lack of power from coil). I've done a LOT of top-end work to the engine (after verifying the bottom end was solid and already had aftermarket pistons, solid compression, etc). I've got the Auto-Tech Sport Cams, Sport Valves and Springs, Titanium Retainers, Lifters, Adj. Cam Gear and L/W intermediate gear along with the 11mm Shock Therapy plug wires.


If you could, also, please, see my other post? I installed the Power Module and now I'm having the infamous, "No fuel pump prime and no power to coil" issue ever since. I've double checked everything I touched when installing the power module and have even removed it.

I do not have a bentley for her yet, but will be ordering one next week. This is my only car right now and I really need to get her back up and running. It's frustrating because I NEVER had any start issues prior to wiring up that damn power module.