[img alt="Ok guys, my son bought a 1990 Camaro RS and we got it last week. It has the 5.0 and an automatic. We have slowly started working on it and it was idling high, running rich and not running well. After some research I have come to the conclusion that this is my problem. Can anyone tell me if this is the right ECU and what CALPAC and PROM. I need? That is if those are even the right terms? TIA
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Ok guys, my son bought a 1990 Camaro RS and we got it last week. It has the 5.0 and an automatic. We have slowly started working on it and it was idling high, running rich and not running well. After some research I have come to the conclusion that this is my problem. Can anyone tell me if this is the right ECU and what CALPAC and PROM. I need? That is if those are even the right terms? TIA First post so please forgive any errors.

 

Can you post a picture of the ecm and silver sticker on the prom. It would have a 1228746 ecm. Any stored codes or vacuum leaks found ?

 

I thought I did. Let me see if I can figure it out.

 

code 51

 

There will be a service number sticker on the ecm. It looks like a 1228746 with no prom installed. Your running in lhm

 

 

Hope these come through and help.

 

It’s a cardone refurbished ecm, I can’t make out the numbers 778746 ?

 

https://www.ebay.com/itm/31333922303...mis&media=COPY

I can burn a copy of this tune without the antitheft if that’s your ecm. Or if you think the security vats system is working this would be the chip needed for 89-92 tbi 305 automatic transmission.

 

Sorry. It didn’t transfer well. EM8746S

 

I think the VATS has been bypassed as the key does not have a chip.

 

The missing prom the ecm wouldn’t recognize a missing hz signal from the passkey if not working properly. Might try the linked prom or can message me I can do a vats delete chip.

 

pretty sure that’s a cardone number for the ecm for your application

 

Are there supposed to be chips in both spots?

 

Kind of figured it was something like that.

 

the 1228746 has the calpak soldered in .It was v8 use only .unlike the 1227747 truck ecm. It just needs a prom.

 

Will it matter if the VATS has been bypassed and still do VATS deleted one?

 

the passkey key cylinder reader reads the resistance of the key tumbler or if key cylinder has been bypassed with a resistor at the bottom of the column. Once the passkey module sees the right resistance it sends a 30hz signal to the ecm. A hand shake of sorts. With the prom missing it doesn’t know if vats is working or not. A vats delete chip would eliminate a handshake and enable injectors without the passkey signal. There are often reference to the key cylinder as a bypass or a hz modulator. The only way to fully bypass is in the chips tune.

 

Sound good. Thank you for the info. I will probably get back with you and have you burn me one.

 

Great info. Thank you.