Unique Fuel Pump Issue

2000xp8

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Aug 8, 2003
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I'd get a Mass air meter calibrated for 24's to match your injectors.
Then pull the chip the stock computer will easily run an X engine.
While the caps are at failing age, i'd find it hard to believe they failed because you dropped a wrench on the battery.
A desoldering pen or wick and a decent iron and you can replace those capacitors in a couple minutes.
 
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CUAviator

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Jan 11, 2015
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I'd get a Mass air meter calibrated for 24's to match your injectors.
Then pull the chip the stock computer will easily run an X engine.
While the caps are at failing age, i'd find it hard to believe they failed because you dropped a wrench on the battery.
A desoldering pen or wick and a decent iron and you can replace those capacitors in a couple minutes.
Mass Air - Copy
Pull Chip - Copy

next part = I agree completely. What I am trying to figure out is what else i need to do - immediately after the short, the fuel pump would not turn on and car wouldn’t start. Pulled the fuel pump fuse, saw it blown. Also saw the EEC fuse blown.
now when I turn the key on, fuel pump won’t stop, but car starts immediately, but then surges like crazy.
* I ordered a new A9P today. We’ll how that works. But I’m thinking there may be something else.
 

John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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B

Thanks for the insight into the chip. The one thing I know it does do is keep me from getting a ton of emissions codes from all the parts that have been deleted (some of which I don’t know if it’s important to the engine properly functioning)

As for the computer - I have an A9L but want to swap for an A9P since I have an AOD. With that link you sent, I know they normally repair what you send in, but can they swap out or redo mine for an A9P?

Go to the ebay auction page and send the seller a question about getting a different model unit than the core you send in .

However, there is also the configuration of the O2 harness to consider when changing from A9L to A9P and vice versa. The O2 harness plug is jumpered differently for each ECU. I believe an A9L can be be used in either configuration without problems. However, it you put an A9P into a car when the O2 harness is jumpered for an A9L, you will fry the A9P as soon as the key is turned on. So, it's possible for your O2 harness to currently be configured either way, and the A9L would have survived. But, if must be configured for A9P, if you in fact put an A9P back in.
 

John Dirks Jr

there is enough sticking out to grab on to
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If you harness has had any modifications to it from the original eec iv configuration, I'd be really careful about changing to the A9P. This O2 harness jumper is very important when using the A9P. If this is wrong it can fry the new ECU real quick! This and any other modification that may have been done to the harness could spell disaster since you are planning to change ECU model. If an A9L was in there, we know that should survive moving forward. Swap to the A9P........??????? Who knows....

Fox 5.0 O2 sensor drawing.jpg
 
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John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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I may have it backwards but either way you need to be sure about this. Maybe someone can chime in and help my foggy memory.

Is the risk of changing detrimental to the A9L or the A9P? It's one or the other but I can't remember for sure. Sorry for the confusion. Just make sure you get it right!
 
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CUAviator

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I may have it backwards but either way you need to be sure about this. Maybe someone can chime in and help my foggy memory.

Is the risk of changing detrimental to the A9L or the A9P? It's one or the other but I can't remember for sure. Sorry for the confusion. Just make sure you get it right!
Everything I’ve seen says that the AOD harness cannot work with the A9L. However a manual harness can work with the A9P. But I also could be misreading that.
 

General karthief

wonder how much it would cost to ship you a pair
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CUAviator

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Jan 11, 2015
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The capacitors definitely need replacement.

Avoid Radio Shack electronic parts whenever possible. Digi-key, Newark, and Mouser are some of the top ones that come to mind. Look for caps with 105° C or higher temp rating and the longest hour rating you can find. The cost difference between the cheapest and the best is usually less that $1.
Do you know if there is a way to check if the diagnostic port is functioning properly (or if maybe it got shorted out)?
 

CUAviator

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What makes you think it's shorted?
Good news...it’s not! I got my new computer yesterday and installed it today. Fuel pump primed as it should, car started, I was able to drive it, and able to dump codes (of which I asked about in some separate threads).
I was worried because before I switched out the computer, I wasn’t able to get the diagnostic port to do ANYTHING even though the car would start.
 
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