Hello,
I have a 1985 v-6 f-bird that gets driven quite a lot. I have done a lot of work to her, ignition plugs, wires, cap, oil seal, intake, tps, etc.
I was getting 28mpg on long trips and power was fine.

Now, however, I am getting inconsistent power and poorer gas milege.

It's weird, I can feel my car "pulsate" while on the freeway--like someone is cutting out the power. When The timing is set to the 10 degress, the car has no low end power.
The car started and stalled the other day and the light came on.... checked code and it gave me # 3-4. The book says MAP.

Other minor glitches to the car include hesitation when cold, sometimes a rought idle.
Is the MAP suspect? If so, how much do they cost usually, I am on a very limited budget.
Any other hints?

Thank you everyone (for your time in reading this),
Rick

 

Well, you don't have an MAP sensor, you have the MAF sensor. They're about $100 (w/lifetime warranty) through an auto parts chain store, or around $300 from GM.

There's a few non-technical ways of checking the MAF. Sometimes a MAF sensor can be bad, but the computer can't tell.

The technical way? There's the GM diagnostic chart, which checks out all of the wiring for you. Your problem could be as cheap as a bad relay or bad MAF connector. Here's the link to the chart, give it a run-through. I was very thorough in describing where all the MAF components are, so it shouldn't take you more than an hour. It'll probably be less since you seem like you're already familiar with your car. https://www.thirdgen.org/messgboard/...ML/001291.html Just do me a favor and let me know if you use the chart or not. For some reason, nobody seems to use it; seems like a waste of my typing. So let me know! Thanks.

[edit] Oh- started & stalled sounds like the MAF. When you slow down for a stop, does the car act like it wants to stall? That's also an indication of something wrong with the MAF system.

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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

[This message has been edited by TomP (edited April 27, 2001).]

 

Thanks for responding TomP.
Well, you never guess what the problem might have been.
--well I got a K&N filtera while back annd I must have added too much oil to the filter element (I live in a really dusty area so I thought it would be better) well I found that the car had sucked up some of the red goop into the mesh part of the MAF. There was also a small piece of paper in it!
So I cleaned everything out and the connections look good. It seems to work fine.
I am keeping my Timing set at 12 degrees (I like the added throttle responce). I have a question, as long as the car does not ping ( which it is not doing), will the slightly advanced timing undermine some sort of performance? Will the slightly advanced timing reduce gas milege?
again,
Thanks for your insight.
PS: If I have any more problems I will use that handy sheet you made. I would rather spennd a little time than waste money!
I just replaced my heater core, 6 hour job! $20 part, I know I saved money on that job!
Rick