1997 Mercury Marquis 1997 Mercury Grand Marquis shows lean,

1997 MERCURY MARQUIS
105,000 MILES • V8 • 2WD • AUTOMATIC
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MARKEE
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Periodically, I will be going highway speed and my engine will stall. Accelerating makes the car decelerate even faster. If I pull off the road and let the car idle, sometimes even less than a minute, I have full power and the car accelerates normally, to repeat the frustrating process again in a few minutes.

It has periodically happened since I've owned the car, with varying results on fixes. Here's what I have found out and had done:
1) check engine code says car is running lean
2) had fuel system cleaned by mechanic a couple of years ago, restored power (but it happened again)
3) used more than one injector cleaner recently
4) now it does the same thing when I start the car (rough start, engine coughs and bogs down on acceleration, then catches and accelerates, usually when I let off the accelerator)

Thanks so much for your help!
Mark
Jul 8, 2009 at 4:25 PM
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RACEFAN966
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Ok have you cleaned the Mass Air Flow Sensor? If not then get a can of Mass Air Flow Cleaner (nothing else) and remove the MAF sensor and spray out the inside really good and then re install it and see how it does. Also is the check engine light on? Here is a pic of the MAF sensor. Let me know how it goes.


https://www.2carpros.com/forum/automotive_pictures/249564_808488_1.jpg

Jul 8, 2009 at 9:07 PM
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MARKEE
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Thanks so much! I sprayed out the MAF really well, reintalled it, and the car started up beautifully and ran like a top down the highway!! That's the first time I've been able to start it without trouble in a couple of months. Thank you so much!!!!
Mark
Jul 11, 2009 at 1:19 PM
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RACEFAN966
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Well thats great, and it didn't cost a lot either. Glad to hear its running right again. If there are any more problems just let me know. Thanks for you support as it is you and the others like you that keep us going. Steve
Jul 14, 2009 at 9:22 AM