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Old 10-20-2007   #11
gbrtng
 
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Default Re: Normal Fuel Pressure

Quote:
Originally Posted by Dandy97
Well I swapped out the ECM after my son's football game and we fired it up and went for a ride. It ran perfect from the moment I started it up. I'm pretty happy I finally got to the bottom of it. Makes me wonder what in the ECM was failing, I'm thinking the injector drivers.

Tomorrow I think I'll hook up the Tech 1, go for a drive and see how everything looks. I'm also going to send in the old ECM for a rebuild, that way I'll have a back-up.

Now that I got it running good I can put in my Fidanza aluminum flywheel!
I doubt that the three low resistance injectors caused the ECM problem because they weren't really THAT low. From my experience it takes almost a complete short to wipe out a driver. Good luck on finding a rebuilder who will give you a post mortem ...
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Old 10-22-2007   #12
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Default Re: Normal Fuel Pressure

Quote:
Originally Posted by gbrtng
I doubt that the three low resistance injectors caused the ECM problem because they weren't really THAT low. From my experience it takes almost a complete short to wipe out a driver. Good luck on finding a rebuilder who will give you a post mortem ...
I wasn't really expecting to find a rebuilder who would do anything except rebuild. I was only speculating as to the failure mode, as you are that it isn't the failure mode.
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Old 12-04-2007   #13
Paul Workman
 
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Thumbs up "vacume leak"

Quote:
Originally Posted by bradslt5
man thats go to drive you nuts. the only thing i can think of other than the ecm would be a vaccume leak or i wonder if the fuel tank recirculation could cause this. one easy way to ck for vaccume leaks is to attach a 2-3ft hose to the end of a propane torch and just turn it on a little if you get an area that has a leak the motor speed will increase. on last thought you might ck around the plenum gaskets and throttle body. they might have a leak cold and it seals once things expand. dont know if this helps just thought to throw out some ideas . good luck hope you figure it out soon
I agree w/ you. The part about stumbling, and "coming on" with some load (read: extra fuel being added) are classic symptoms of a 'vacume leak' in the open loop mode.

However, running OK when it warms up could mean that expansion is closing up the (gasket?) leak. But, it may be due to the fact that when it warms up and switches to "closed loop", the O2s sense the lean condition and the computer compensates by riching up the mix. This may well result in an increased idle speed in "closed loop"...or not...depending on method of idle control and/or where the leak is.

Just a thought!

P.
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Old 12-04-2007   #14
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Default Re: Normal Fuel Pressure

The ECM turned out to be the problem. Car runs like new now. Too bad the weather turned or I would still be driving it every day.

I put in the Fidanza flywheel a couple weekends ago and that turned out to be a great mod. The extra fun factor is worth the small amount of extra gear noise in my book. I also found my small transmission fluid leak and fixed it. Just when I get everything running right, winter shows up. Only about 12 weeks to go...
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Old 12-04-2007   #15
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Default Re: Normal Fuel Pressure

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Originally Posted by Dandy97
The ECM turned out to be the problem. Car runs like new now. Too bad the weather turned or I would still be driving it every day.
Who rebuilt the ECM and how much $$$ ?
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Old 12-04-2007   #16
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Default Re: Normal Fuel Pressure

Way to go there Dandy!!

Hey dere what part of WI are you in?
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Old 12-05-2007   #17
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Default Re: Normal Fuel Pressure

Quote:
Originally Posted by gbrtng
Who rebuilt the ECM and how much $$$ ?
I purchased one from Parts America when they still had them in stock for $119.00. I do want to have my old one rebuilt. I found a place in Jacksonville FL that will rebuild them for $219.00 including shipping. They also sell rebuilt ones outright for $499.95. It's Called ECU Direct and they claim they have a lifetime warranty on their rebuilds.
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Old 12-05-2007   #18
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Default Re: Normal Fuel Pressure

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Originally Posted by WB9MCW
Way to go there Dandy!!

Hey dere what part of WI are you in?
I'm in Greenfield which is on the south west side of Milwaukee. I drive through McHenry every time I go down to St. Charles, I'll have to stop and say hi next time.
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Old 12-05-2007   #19
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Default Re: Normal Fuel Pressure

Quote:
Originally Posted by Dandy97
I'm in Greenfield which is on the south west side of Milwaukee. I drive through McHenry every time I go down to St. Charles, I'll have to stop and say hi next time.

Sure no doubt on the way to BG each year right?

Just Pm me b4 you make all the plans and we will be glad to have you stop by for an eyeball
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