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Discussion Starter #1
So my 88 A9L MAF conversion GT vert that I gave to my son started running bad at idle and lower rpm but ran good WOT. Since I wired up a CEL in the conversion, we ground the correct test pin and the light flashed Code 66, bad MAF signal. No problem, we put a new sensor in it less than a year ago so we swapped for a replacement. Same thing. I knew the wiring was good because it ran fine for a couple of years after the swap. So, we pull EEC and disassemble for a look. At first glance, didn't see an issue, so I get out the magnifying glasses and I notice discoloration under an electrolytic capacitor. When I give the can a little push, I can see one lead has corroded away. Since these computers now go for $150-$250, I decide to get capacitors. Solder them in and now things are back to normal. Below is a pic of the board showing where the 3 electrolytics are located and their ratings. I had to buy 10 sets of repair capacitors as that is the smallest amount I could find online. Since only the one was failed, that one is associated with the MAF processing circuit. Thought you guys might like to see this info. If anybody wants one of the 9 repair sets (3 capacitors) I have left, $5 shipped to your mailbox. PM me for my address.

 

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Good job repairing.

When you or anyone runs out of parts, any reasonable voltage greater than original can be used (say up to 3 times). Capacitance can be at least doubled without issue. Most of the time capacitance can be several times original.

The function of those parts is to bypass noise to ground, so more capacitance generally does not hurt as long as the part fits. The real issue is lead size and spacing to fit holes.

Hows that LS volvo?
 

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Dean Scheidt
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Thank you for sharing. I'll save this info in case my A9P has a similar problem some day.
 

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I sent you a pm. I will take a set.
 

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Indo-Canuck-Yankee
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Did you replace the caps with the original aluminum liquid electrolyte type or did you find some polymer e-caps? I've noticed that all EEC-Vs only use polymer e-caps, probably making them many times more durable than EEC-IV with liquid electrolyte.
 

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Discussion Starter #7
I'm pretty sure they are the polymer type - they are slightly smaller even though the ratings are exactly the same. They are also black with gray negative strip versus the original blue cans
 

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Indo-Canuck-Yankee
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I'm pretty sure they are the polymer type - they are slightly smaller even though the ratings are exactly the same. They are also black with gray negative strip versus the original blue cans
Sounds like I ought to grab a set myself! Thanks!
 

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Tip: Keep the capacitor leads longer, on the cap near the J3 port, so it can be bent out of the way for any future chip install.
 

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This was surprisingly easy with a solder puller. Total time was 2 hours. My capacitor for the MAF was shot and the neg lead was corroded and loose. Would explain my recently varying idle. Now it idles very deep and hits solid, not fluttering like before. Thank you.
 

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Indo-Canuck-Yankee
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So what parts is everyone using for their refurbish job? The newer EECs have those solid state caps that are supposed to last a lot longer... I believe they are electrolyte free.
 

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I used the above mentioned caps from Tmoss.
 

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Indo-Canuck-Yankee
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I used the above mentioned caps from Tmoss.
Yes, but I'm referring to specific part numbers and manufacturers. You know, like TI DM3686 or something like that.
 

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Discussion Starter #16
you can buy the newer design caps with the same ratings as the originals, you don/t need a part number. Search on Amazon with the cap ratings and they will come up. You have to buy multiple caps as they are only sold in small lots at decent discount pricing.
 

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Indo-Canuck-Yankee
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you can buy the newer design caps with the same ratings as the originals, you don/t need a part number. Search on Amazon with the cap ratings and they will come up. You have to buy multiple caps as they are only sold in small lots at decent discount pricing.
I was going to simply add the part numbers to my company's next order for parts. We have accounts with Mouser, Allied, Newark, Digikey, etc.
 

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Does anyone have any good close up pics of where the capacitor leads should be going to? When the caps leaked it ruined the leads on the board , I might need to make some jumpers
 

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I had the exact same capacitor go bad on my X3Z. MAF voltage was all over the place. I was able to get single capacitors, 2 of the 47's and 1 of the 10's, from Mouser. They cost me more to ship them than what the capacitors cost. After installation of them my voltage is now as it should be.
 
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