i love it when folks rattle there you tubes.
i thinkyou need a new sound driver...... nah. just kid'n.
that is one wierd sounding motor. its coming out of the air horn huh?
unplug the iAC ,
could be lots of things.
besides a head valve intake.
it is seriously wrong. Mine just sucks and a whistle real high on top.
does it go away.
pinch some hoses, heck pinch them all 1 by one. even the brake booster. Vac hoses.only.
1 :iac bad.?
2: egr spring in side collasped and it just flops around. (feel it with finger, the diaphragm)
3: one guy here had a Lincoln cont. PCV valve installed and it did wierd stuff.
4: im think'n, hahahahah
fiddle all connected to intake ,leave nothing.
one guy had a bad TB gasket the fluttered side to side wierdly.
congrats you get the weird Kick award of the year,!!!
let fix this puppy.
cheers.
I'm waiting for the other shoe to drop here. If the IAC is good, what should happen when you unplug it? I assume if it's bad, nothing will happen when you unplug it. Should the unplugging be done with the engine hot or cold?
When I unplug mine it drops the engine RPM's and idles rough until it can level itself out the best it can, plugging it back in revs the engine and then it settles down. (Does this when cold). I do no think this would cause the noise you are talking about though.
Have you checked the timing any? Since it is an 8v it won't mess the engine up but it would be best to check since jtgh is talking about valves...
does your noise only happen on a hot ? cold engine. or both??
the IAC only controls hot idle but unplugging it usually will cause the idle (IIRC) to drop.
(it dont matter which way, as all you are doing is seeing if the IAC is causing the noise)
i am confused , two posters, slyattacks and longrod. that's ok, but you need to
put your cars spec in your sig. or somewhere so i can see who and what.
89-98 is a wide path.
nothing happens is correct, in the noise department. not the idle speed.(clarifying)
we are troubleshooting induction noise, I'd play with every thing on the inductions side
first to find something that effects the noise.
a compression test is always a #1 test on ANY engine not running good ,as is a tune up.
the reason I am unsure, is because (iac) is because on some engines, the induciton has excess air, so IAC closes to compensate, on others, there is insufficant air and the IAC opens to add more. (The ECU does this)
a burned Intake valve or (freezed damage) can make the induction do funny things.
The ECU will be going craZY to compenate for any serious damage and will fail in two regards, AFR and idle. ( it might start hunting)
What is hunting. ?
that is when a servo device can not keepup with the changes and starts over correcting. (if the induction is bouncing (unnaturally) the ECU will be beating the IAC to death trying to keep things normal, and will be unable to do so.)
cheers
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91'-8v,2dr,4wd,Conv. Market#E03
My server has Engine Repair proc/data. Check it out.
I did the vac test and all is good. My sound is both hot and cold. I did a valve adjustment and from the top side found no problems. I’ve removed, clean and played with everything on the intake side but nothing changes the sound. The EGR spring is good. I’m thinking of putting in new intake and TB gaskets just to see if it helps. I still need to do a compression check… but it’s still running great. At what RPM should it idle when cold?
1200 cold and 800 hot.
even faster with Dashpot for 3 to 10 seconds then down to IAC thermal.
the IAC thermal sets the min. cold idle with a moving wax pellet.
after warm up the IAC thermal closes and the IAC electric is used by the ECU to hold any idle ,you ! set.
you set it and IT (ECU) holds it , no matter what.
a compression test.?
pull fuel pump relay during the test and the coil input lead.
then wide open throttle all plugs removed and check each.
no shocks (pain is bad), no fuel. fire is bad. MSD shocks , horrific my knees are shaking , just the thought.
FP relay is above knees, green socket.
if you have any air leaks the car will never hold 800 rpm hot.
never.
there is an idle bleed screw on the front of the air horn behide a rubber plug.
8v enigine mix AFR perfect with any air leak and only just idle faster.
if you have a leak and it idles fast the air bleed will be inop. (or you will not be above to drop to 800 hot)
if the hose pinch test shows no rpm drop and idle is high
then there is a leak.
that noise is strange.
sure sounds like a sticking intake valve to me and others i sent it to.
i have a mechanics stethoscope $3 at harbor frieght.
down the air horn it would go and just see if the flutter is coming from inside.
(i bet you already know where , huh)
you said the PCV is fluttering.
that is normal but you shouldnt here it. how are you hearing that.?
you got 20 inchs at idle ( mine runs 19) and it does not flutter.
at the Evap nipple or in place of the brake booster hose?
not that many legal taps. EGR Nipple is wrong , its ported, as is FP reg.
got to be below the throttle plate vac, source.
strange you can hear it flutter but not measure it.
try plugging the PCV hose at man. side, and letting the valve cover freely vent.
it should just emit a stream of nasty gas. it will flutter with the piston movement.
some people discover a huge stream of gas comming from the crank case.
due to cracked piston, or completely stuck down rings.
the rings can get weak and collaps in the lands, leaving tons of blow by gas.
this gas over loads the PCV and the intake side.
the compression test would have already alerted you to this problem.
open up the pcv VALVE COVER Side.
you could just take off the oil filler cap and note any gross emmisions.
the reason i want the PCV valve off, is to see if the intake stops its bad sound.
those are my ideas, hope they can help you.
cheers.
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click me.
91'-8v,2dr,4wd,Conv. Market#E03
My server has Engine Repair proc/data. Check it out.
they look diff. but do same thing , same way. 8v TBI 1.6 liter.
6.7 seems way too low.
12 ohms maybe. i will look it up later. and tell you.
make sure all ports are clean on it and the TB.
many things can cause the ECU to stop controlling idle.
besides obvious IAC electric valve.
TPS Switch side not closed signalling idle ( cases engine to die , ECU DROPS IDLE RULES)
it can have no effect if you have tons of air leaks,
this happens because the IAC can not stop the leaks and so it just closes.
getting an IAC to work correctly can be very hard.
the fsm warns about the fact that all other things must be correct before the ecu can control idle.
a big list.
but top items.
1: no air leaks in the induction. (does engine race at hot idle , too fast ?????)
2: ECU must not be in limphome or worst backup mode
3: ECU most not THINK engine i overloaded. (gross drop in vacuum will signal that)
4: TPS switch must work. (signaling idle).
5: ECU itself must not be sick or at least not have dried out capacitors,per my page.
6: AIC electric bad.
7: IAC thermo stuck wide open hot ( see #1) just another air leak to the plenum.
__________________ http://carfix.stufftoread.com/
click me.
91'-8v,2dr,4wd,Conv. Market#E03
My server has Engine Repair proc/data. Check it out.
Linear Mode
