View Full Version : Why does it suck?

03-30-2008, 02:26 AM
Most cars, when you trun the key off, no more noise is heard from the motor, thats that. However, when I turn my car off it makes a sucking noise and it sound like its comming from the throttle boddy. It makes the same sound as if you would suck on your palm and release it ( don't do it if your hands are grimmy :eek5: ) I have never owned, operated or heard a 2.5 shutting off. Is this normal for this motor or is someting odd going on? Its not detonation because I cleaned the pistons and head before I put it on.

87Cutlass Ciera
03-30-2008, 03:28 AM
go out to your car now, if it hasn't been running and try to change the setting on your HVAC control (Panel, to heat, to defrost, something different) if you hear a sucking then I don't know, if you don't hear a sucking, you have a vaccum leak. Now I'm assuming that the HVAC controls for these cars with A/C are vaccum actuated, I don't know as mine is just the basic. My fathers ranger used to do this too, and it was the choke selonoid, or something along that lines, completely normal. I can't go and listen to mine as I don't have it. I think you're worrying too much, if it works, then don't fix what's not broken.

03-30-2008, 03:29 AM
no vaccum leaks my car runs fine i have fi

04-02-2008, 12:25 AM
My 3300 does this too. only noticable if the hoods open. It's coming from the throttle body, yes. I suspect its the abrupt stop of the engine, perhaps a piston rolling backwards a little bit, one of on the intake stroke going back up a touch blowing air OUT.

Just a guess.

04-09-2008, 02:38 AM
I've had a few 3800s that do the same thing

04-09-2008, 04:23 AM
my 350 tbi has done this forever........i dont think is any thing to worry about............it seem that the rest of the car will kick the can long be for this 94 350 with a cracked head and leaky intake gaskets at 267k will............everything is dieing but hte motor is still running and not blowing smoke of any kind.

04-09-2008, 03:50 PM
It does it only every now and then.