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Slotted P28 with J1 jumper question...bad ecu question

16K views 14 replies 7 participants last post by  christbone20  
#1 ·
So, I purchased a P28 that had been slotted and ready for boost. But for whatever reason on the dyno the tuner's emulator couldn't "read" from the slot and I was told it was no good. Checked the soldering and the tuner said it was about the best soldering job he had ever seen; so we didn't suspect that. Used two other slotted ecus from around the shop and they worked and my car was successfully tuned. But back to the "bad" ecu. If I were to merely cut the J1 jumper, would the P28 revert back to OEM/stock...even without that chip that was originally there where now the slot resides?

Thx!
 
Discussion starter · #8 ·
Did it run fine before you got on the dyno with a regular map? Cause if so, the problem was prob with your tuner's emulator not the ecu. However, I'm sure he already checked that.

You can still have a fried ecu with a nice solder job. I have a p28 that looks perfect but wont start the car. It was shorted out at some point and is no longer good. Chances are if it wont start a car with the chip its prob not going to start it with J1 cut. But its worth a try, goodluck!
Thanks everyone! I'll have to give that jumper a cut this week!

I was actually running the turbo'd hatch on this "bad" ecu in limp mode. But I had no idea that's what it was cuz I had had a basemap burnt for me and I just figured it was running rich and blogging cuz of the basemap. But all along it was just a "bad" ecu. So yea, the ecu works...it just doesn't seem to "see" the slot/chip.

Definitely wasn't the tuner emulator because that didn't change and we tuned my car on another ecu later on that same day!

Oh, I know you can...cuz I fired my other one with somehow incorrectly wiring inline resistors (don't ask, we all still cannot figure it out). It did start my car and it ran, in limp mode.

So with this addition data maybe I can get even more of ya'll to comment on what you think.

Thanks!
 
Discussion starter · #14 ·
Pics, now why didn't I think of that! LOL

Regarding the solder job...my tuner myself himself said that everything looked top-notch and better than his own solder work. LOL! So I'm sure that the soldering wasn' the issue.

The tuner de-soldered the slot, removed it, inspected it, and re-soldered it back in...but no change.