Mechanics

JERKING WHILE COASTING

1990 Buick Century • 200 miles

My car****** while im coasting sometimes when mantaning speed depending on how fast im going (it****** bout every 3 secs.) If I switch to neutral it stops. To me it kinda sounds like its attempting to died. Ive changed the mass air flow sensor. Witch was bad
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Blablablabla38
September 30, 2011.



Check fuel pressure which shold be no lower than 40psi. Clean the throttle plate and iac valve hole with choke cleaner. Do this with engine off. It will start hard after doing this.


Hmac300
Sep 30, 2011.
So if my fuel pressure is lower than 40 would you stay the best thing to change would be the fuel filter


Tiny
Blablablabla38
Sep 30, 2011.
Actually no the best thing would be to replace the fuel pump and filter. The pump is probably going bad.


Hmac300
Sep 30, 2011.
Also I belive the hiccups get worse when im low on gas


Tiny
Blablablabla38
Sep 30, 2011.
I got told by one of my friend a mecanic that it might be a motor mount is that a posability


Tiny
Blablablabla38
Sep 30, 2011.
Chances are hmac is correct with the fuel pump. A motor mount could cause it, but it's unlikely. You are most likely to feel a clunk when placing it in gear.


It does it after its already in gear. I beleve it does it with all the gears. Could the oxgen sensor be any problems to this becasue I know thats why my check engin lights on


Tiny
Blablablabla38
Oct 2, 2011.
It could because it tells the computer how rich or lean to make the fuel mixture. If you have had the computer scanned, let me know the codes you found.
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Ive had the little key inserted in the computer connector and code 33 shows up its the maf. Ive used a light up tester on the maf connector while the car was on and none of the wires have any juice on them. Would you be able to get me the wireing diagram?


Tiny
Blablablabla38
Oct 8, 2011.
I've sent two charts, one shows howit's wired and second chart shows how to check it. Chekc your ecm fuse in the fuse box first though as that is where it gets it 's power


Hmac300
Oct 9, 2011.
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