Replace Ecm
Thread Starter
Instructor
Joined: Jun 2003
Posts: 128
Likes: 0
From: tampa fl
Replace Ecm
It's for sure the ECM is bad, need suggestions, every day driver, not raced. best bang for my $$$. What do you suggest? Is the change over easy, and whats the best procedure for accomplishing it.
thanks
ROCKY85
thanks
ROCKY85
Race Director
Joined: Jun 2001
Posts: 10,956
Likes: 682
From: Marlboro country MA
A couple of years ago I replaced mine. Cost $100 for a rebuilt unit, plus the core charge that was refunded upon sending back the old unit. It's a very easy job, perhaps 15 minutes or less. Just disconnect the old unit (after disconnecting the battery), swap it out, and hook up the new unit. Oh yes, don't forget to unscrew the little door on the bottom and retrieve your mem-cal. That's the memory that needs to be transferred to the new unit.
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Originally Posted by Corvette0096
Listen to me on this one.. Get a acdelco rebuilt one. The swap is easy. Marcho polo has a tech tip on the swap. I just took back my third A1 Cardon POS.
Bad news Rich, guess who rebuilds ECMs for AC Delco........you got it, A1 Cardon
Race Director
Joined: Aug 2000
Posts: 11,506
Likes: 4
From: Vancouver,Wa.
Originally Posted by tjwong
Bad news Rich, guess who rebuilds ECMs for AC Delco........you got it, A1 Cardon
Hum.. When did that happen? I just bought one from Beach bum and the date on the thing is 10-03
Instructor
Joined: Apr 2002
Posts: 223
Likes: 0
From: Spokane Wa
Get a used one
Most good recyclers can look up what unit will cross reference. I used a unit from a pontiac 6000 once ( I Don't remember what year.) in an 85 corvette. Out side looked exactly the same changed the chips and I was off and running. Cost me $50.00. The car is still running and this was six years ago. This option will be harder or maybe not work at all. On cars that the chip cannot be changed. Got to love those L-98's
Mike
Mike
Thread Starter
Instructor
Joined: Jun 2003
Posts: 128
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From: tampa fl
Quick question now that I have installed a bypass switch to the fan when I replace the ECM can I leave it in place this would be a distinct advantage given the hot climate here in Florida.
Thanks
Rocky
Thanks
Rocky
Instructor
Joined: Jan 2002
Posts: 221
Likes: 0
From: League city Texas
What symtoms did you have that lead to the bad ecm diagnosis? My 85 started acting up on the way home from work. It appears to be an ignition problem but none of the usuall items ie spark plugs, wires, cap rotor, coil or ignition module are the problem.
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Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
As I understand it it's the PROM that makes the difference.
Mine is a 7165 and any car that uses the same one, like many of the 'F' bodies (Camaros, Trans Ams, etc.) will work.
The 85 has a different ECM though; it's, I guess you'd call it, first generation with a slower baud rate.
A few years ago when I had to replace mine, I got it at O'Reilly's auto parts for $100, remanufactured, which folks claim is different from "re-built".
Who knows, but it's still going strong.
If I have to replace it again , I'll be heading to the wrecking yard.
Like the guy in the fat wife commercial said, "Youbetcha!"
Jake
Mine is a 7165 and any car that uses the same one, like many of the 'F' bodies (Camaros, Trans Ams, etc.) will work.
The 85 has a different ECM though; it's, I guess you'd call it, first generation with a slower baud rate.
A few years ago when I had to replace mine, I got it at O'Reilly's auto parts for $100, remanufactured, which folks claim is different from "re-built".
Who knows, but it's still going strong.
If I have to replace it again , I'll be heading to the wrecking yard.
Like the guy in the fat wife commercial said, "Youbetcha!"
Jake
Thread Starter
Instructor
Joined: Jun 2003
Posts: 128
Likes: 0
From: tampa fl
The Mr. Goodwrench has a shop next to my office, when the cooling problem occurred, we swapped relays to the ac and no problem, than the fan quit working on the max ac setting, and upon checking there was no signal coming from ECM to the relay. He told some of my other symtoms may be corrected after replacement.
Drifting
Joined: May 1999
Posts: 1,478
Likes: 3
From: Sacramento, CA Money can't buy happiness - but it's more comfortable to cry in a Corvette than a Yugo.
Originally Posted by ROCKY85
Quick question now that I have installed a bypass switch to the fan when I replace the ECM can I leave it in place this would be a distinct advantage given the hot climate here in Florida.
As MTVette stated, BE SURE to remove the MEMCAL chip from your old unit before giving the core up. It is a PROM (Programable Read Only Memory) chip in a light blue (usually) plastic housing. The MEMCAL is specific to your vehicle year and transmission type. Treat it like the delicate electronic component it is. Don't drop it or touch any leads.
NAPA had rebuilt AC-Delco units for about $115. About 6 months after I bought my 88 I had my ECM replaced with a "Genuine GM" unit at the dealer. After 14 months it went bad again. The second time, I went to NAPA, and installed their rebuilt unit myself. Haven't had a bit of problem in over 5 years.
Oh yeah, the dealer charged me for an hours labor at $90/hr to do a job that takes 15 minutes. Never going to a dealer again.
