Engine Bad A9L computer?

91GTstroked

15 Year Member
Jun 14, 2007
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Hey guys,

Some know I've been chasing down drivability problems with my car. No codes giving me an answer. A balance test coming back with a 90.

I planned on getting the tune checked out so my tuner suggested pulling out the ecu to see if it has a chip. I found a kb flip chip. Looks super old.

But I also decided to check out the capacitors. I see green fuzz below one of them. From what I've heard, this is bad.

Also,. I see a ground wire without any insulation around it. Assuming this isn't normal?

I appreciate the help.

Edit: I just noticed one of the capacitor legs is completely gone.
 

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@91GTstroked

That is an electrolytic capacitor or what is commonly called, a cap. They have a definite life cycle and after 22 or more years, they start to fail. The failure mode is they dry out because the liquid electrolyte leaks out. Then they burn up or blow the top out of the can that they are packaged in. A clue to failure is the top of the can starts to bulge. When you see one bulging it has either failed or is in the process of Many of the automotive computer repair places will replace all of them as a first step in any repair efforts. The capacitors have a voltage rating, a capacitance rating, a tolerance for the capacitance rating, an operating temp rating and a life cycle rating. They also have a specification for cab size and lead placement

The higher the voltage rating, the larger physical size of the capacitor when compared to one with the same capacitance and a lower voltage rating. Most of the ones used in automotive electronics have a 20-35 volt rating since they are used in low voltage circuits. Using one with a higher voltage rating doesn't hurt anything, but it usually doesn't have any benefits either. There may be a size limitation because of the way the circuit board is laid out. That means there are sometimes limits on replacing the 20 volt cap with a 35 volt cap because it won't physically fit in the space allocated on the circuit board.

The higher temp rating and longer lifecycle ratings increase the cost of a capacitor. In automotive circuits, those are important factors, and the highest rating stands the best chance of lasting the longest and working the best. Most capacitors used in automotive applications are rated at 105° C The typical capacitor used in most automotive electronics is less than $1.50 each.

Some informative help from YouTube…

View: https://www.youtube.com/watch?v=YCSNWi3UHf4


WWW.digikey.com or www.newark.com are good sources for capacitors, resistors and just about any other quality electronic part. Avoid Radio Shack unless it is a temporary repair or emergency situation. Almost all of their parts are less than top quality stuff and a lot of it is just plain junk.


That's the easy part; now here comes the gotcha... The circuit boards are almost all multilayer construction. That means you have to be able to apply enough heat with a pencil tip soldering tool to melt the solder on at least 4 layers and sometimes more. Then you need to have a solder sucker to suck up the solder once it turns molten but before it burns or damages the PCB (Printed Circuit Board). I have been fixing PCB's in computers for 41 years now and it is still a challenge to do it right and not make a mess of it.
The capacitors have a stripe on the side of the can that indicates polarity. Make sure that you match the polarity markings on the capacitor with the polarity markings on the PCB.

Some more help from YouTube…

View: https://www.youtube.com/watch?v=urGB_IUXSIM
 
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@91GTstroked

That is an electrolytic capacitor or what is commonly called, a cap. They have a definite life cycle and after 22 or more years, they start to fail. The failure mode is they dry out because the liquid electrolyte leaks out. Then they burn up or blow the top out of the can that they are packaged in. A clue to failure is the top of the can starts to bulge. When you see one bulging it has either failed or is in the process of Many of the automotive computer repair places will replace all of them as a first step in any repair efforts. The capacitors have a voltage rating, a capacitance rating, a tolerance for the capacitance rating, an operating temp rating and a life cycle rating. They also have a specification for cab size and lead placement

The higher the voltage rating, the larger physical size of the capacitor when compared to one with the same capacitance and a lower voltage rating. Most of the ones used in automotive electronics have a 20-35 volt rating since they are used in low voltage circuits. Using one with a higher voltage rating doesn't hurt anything, but it usually doesn't have any benefits either. There may be a size limitation because of the way the circuit board is laid out. That means there are sometimes limits on replacing the 20 volt cap with a 35 volt cap because it won't physically fit in the space allocated on the circuit board.

The higher temp rating and longer lifecycle ratings increase the cost of a capacitor. In automotive circuits, those are important factors, and the highest rating stands the best chance of lasting the longest and working the best. Most capacitors used in automotive applications are rated at 105° C The typical capacitor used in most automotive electronics is less than $1.50 each.

Some informative help from YouTube…

View: https://www.youtube.com/watch?v=YCSNWi3UHf4


WWW.digikey.com or www.newark.com are good sources for capacitors, resistors and just about any other quality electronic part. Avoid Radio Shack unless it is a temporary repair or emergency situation. Almost all of their parts are less than top quality stuff and a lot of it is just plain junk.


That's the easy part; now here comes the gotcha... The circuit boards are almost all multilayer construction. That means you have to be able to apply enough heat with a pencil tip soldering tool to melt the solder on at least 4 layers and sometimes more. Then you need to have a solder sucker to suck up the solder once it turns molten but before it burns or damages the PCB (Printed Circuit Board). I have been fixing PCB's in computers for 41 years now and it is still a challenge to do it right and not make a mess of it.
The capacitors have a stripe on the side of the can that indicates polarity. Make sure that you match the polarity markings on the capacitor with the polarity markings on the PCB.

Some more help from YouTube…

View: https://www.youtube.com/watch?v=urGB_IUXSIM

Thank you for the detailed information. I'm not sure if this is something I want to tackle right now.

I'm debating on buying a refurbished ECM. I could use this one as a backup.
 
At $450, for a rebuilt one -
I would send mine in to be rebuilt at one of the businesses that has fast turn around for about $130, unless you really want a back up.
 
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At $450, for a rebuilt one -
I would send mine in to be rebuilt at one of the businesses that has fast turn around for about $130, unless you really want a back up.

Do you know of any places that do it?
 
91GRstroked has the answer. I have used these people. If the computer is good, they will tell you. If it is bad they send it back no charge, just shipping. If you have questions or problems, email them and they will help you figure it out. Good luck.
 
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91GRstroked has the answer. I have used these people. If the computer is good, they will tell you. If it is bad they send it back no charge, just shipping. If you have questions or problems, email them and they will help you figure it out. Good luck.
Thanks, I hope to hear back from them early this week. It was delivered to them this past Thursday.