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i have ecu p28 and i want to put a chip in it.
I put two condensers 0.1uf (104-k5k), one resistor 1kOhm and one integrity 74hc373, but I have a problem when connecting jumper to J1 my car don't go over 4000rpms with chip and without the same thing. Does anyone know where the problem is?

 

The J1 jumper tells the ECU to look at the 28-pin auxiliary chip location "27C256" for engine operational instructions... if you didn't install a 28 pin chip with a tune on it, then the ECU detects no instruction and defaults to the "safe mode" on the original ECU chip. Removing the J1 jumper returns the ECU to "stock" operation.

 

I have a chip. but when the chip is in place the same thing does not go over 4000 rpms and no chip.
ok i understand jumper is a breaker and probably i do not read the chip. but why?

 

I can make a couple guesses... either the chip doesn't have a program on it or it has been corrupted, or the chip is (or has been) installed backwards... damaging it. The half moon notch in the chip faces the middle of the ECU and NOT toward the BARO sensor when installed properly.

 

have two chips and none is working?
I recently put another p28 with the chip from the second car the chip was powered by a check engine (twice quick) and the same thing will not be over 4000 rpm. and in that second car it works normally. why? and we have the same engine and the same power