'94 RMS, PCM died on interstate

[Gbuster]

Best place to buy a reman PCM? Reflash stock?
I believe a '95 will work.
Has anyone reflashed to 9C1 spec? Problems doing that?

Funny, dash lit up like Christmas tree.
Coasted down exit exit ramp. Flat bed back home.

 

[HotZ28]

Are you sure that the PCM failed, or could it be another electrical issue? The '94 & '95 RMS PCM is the same, but the E-Prom may be programmed different, such as with rear-end ratio and other variables. Have you checked all battery connections and body grounds? I think Sum Ting Wong with the initial rapid diagnosis condemning the PCM?

1995 BUICK ROADMASTER 5.7L V8 Engine Control Module (ECM Computer) | Shop Now at RockAuto

Electrical Parts and More for Your 1995 BUICK ROADMASTER at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.

www.rockauto.com

 

[Gbuster]

Hope you are right. That was my first thought too. While on the side of the the road, I lifted out the underhood fuse block, looked for any corrosion on the fuse sockets. Also cleaned and retightened the large connection from the battery. Checked and reseated the 10A center fuse (PCM). I have a DVM display permanently mounted on dash, and system voltage was good when engine quit. I have not yet removed the PCM to look for anything obvious. Will have a much closer look at wiring now that I'm home, in particular for a chafed wire, or other defects in that fuse block.

Not long ago a mouse got into my HVAC duct. PIA to remove the stinking thing. It may have chewed some wiring, IDK yet. Soy based wire insulation is
causing serious problems on newer cars. Anyone know if/when GM switched to soy based insulation? Chrysler and Toyota are both currently using it, and mice love it.

BTW, from what I have read, the '94 and '95 PCMs do not have a removable EPROM, as before. PCM should be reflashed per VIN, sellers have told me. Reman from autoparts stores are generic and must be reflashed, so they say.

 

[HotZ28]

I guess I was thinking about a '93 that had the prom. It appears that the '94 is indeed a flash program. Some additional things to look at in the link below.
Don't Misdiagnose Your ECM!
In addition, if the PCM is found to be at fault, you should Contact Rodney at SpareECM 330-473-0426 to see what he can do for you. They are not showing one in stock for the '94 but I am sure he can locate one and program it to your VIN>

Items for sale by spareecm | eBay

Shop eBay for great deals from spareecm!

www.ebay.com

 

[Gbuster]

Best place to buy a reman PCM? Reflash stock?
I believe a '95 will work.
Has anyone reflashed to 9C1 spec? Problems doing that?View attachment 26125

Funny, dash lit up like Christmas tree.
Coasted down exit exit ramp. Flat bed back home.

UPDATE: New (reman) PCM from SpareECM (see Ebay store by that name) fixed everything. The owner is based in Ohio, and he accepts phone calls. I called with a few questions, and he explained everything very well. I would buy from him again for sure.

 

[HotZ28]

SpareECM | eBay Stores (100% positive feedback)! eBay ratings don't get any better than that! You made a good choice.

 

[Gbuster]

Hat tip to HotZ28 for suggesting SpareECM Ebay store! I will post an update after I have put the old ECM on test bench (someday). The ECU in my former '92 Olds 98 3.8L failed at 325k miles. This, several years ago, and I found a shorted driver chip after diving into it.