Use a shop vac with the hose installed at the other end, where it blows instead of sucks. Insert the hose in the tail pipe, and using duct tape seal it in. Remove air filter box. Mix up a solution of liquid dish soap and water, or use kids bubble stuff - you know, the stuff you dip a circular piece in it then blow through it to get bubbles (LOL), and put it in a squirt bottle. Get a mirror and flash light. Start the shop vac blowing up the exhaust pipe then squirt the soap/bubble solution all around the exhaust manifold. If it's cracked it will blow air out and create bubbles. Look for them.
Worked for me. Found one small crack I couldn't see before.
I have a 2.8 v6 4 spd with a high idle (2200-2900) after cleaning my TB and replacing IAC. Im thinking vacuum leak, cracked exhaust mani or that egr pipe. Anyone tried this?
Are you saying the high idle started after cleaning the TB and changing the IAC or are you saying that those are the things you tried already? If it happen after those items it could be a bad IAC or it might be one of the hoses that connect below the throttle body.
------------------ 86 Fiero GT 4spd - L67 swap: VS cam, GenV Build Progress 98 GTP - Some mods
The easier solution is go ahead and get the manifolds welded and replace the EGR tube. If it's a 2.8 and hasn't been touched, those ARE cracked and leaking. Common problem with those.
------------------ 1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...
Bigger issue is Do not use exhaust to blow air into engine. Exhaust can put allot of rust etc into the engine. Not Good.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
Cut a strip out of an aluminum pop can, the width of the UPC. Take off the dist cap (leave the wires on) and put it aside. Loosen the two 10mm bolts (heads) that hold the tube to the bottom of the intake manifold. Slip the aluminum can between the two, tighten the bolts and replace the dist cap. If your high idle goes away it is the tube leaking.
btw, this procedure looks much easier than it is. Take your time and use your fingertips along with your 10mm box/open end wrench.
This procedure costs about $0.35, well that is until Michelle bans soda pop.
[This message has been edited by phonedawgz (edited 09-21-2013).]
Cut a strip out of an aluminum pop can, the width of the UPC. Take off the dist cap (leave the wires on) and put it aside. Loosen the two 10mm bolts (heads) that hold the tube to the bottom of the intake manifold. Slip the aluminum can between the two, tighten the bolts and replace the dist cap. If your high idle goes away it is the tube leaking.
btw, this procedure looks much easier than it is. Take your time and use your fingertips along with your 10mm box/open end wrench.
This procedure costs about $0.35, well that is until Michelle bans soda pop.
[/QUOTE] Thanks, now how about the pressurized smoke can?
Take a Qt or gallon Empty paint can, drill 2 holes in the" Lid". in 1of the holes, epoxy in a air fitting to fit for your compressor air line, the other hole, a fitting you can slip a vacuum line onto. all you do is: put a little oil on a rag, light it up, let it burn for a few seconds, then put I out, but let it "smolder". Put the rag in the can and put the lid on. Put the vacuum line onto a vacuum port on the intake of the engine, then connect air pressure to the air fitting on the lid. **** ONLY USE about 5 PSI of air pressure, or all you'll do is blow the lid off the can)***** the smoke will go through the engine and come Out Everywhere there is a Leak ! very simple, took me about 20 min to make. Hope that helps. feel free to post this if you want. [/QUOTE]
[This message has been edited by NiotaFiero (edited 09-21-2013).]
Take a Qt or gallon Empty paint can, drill 2 holes in the" Lid". in 1of the holes, epoxy in a air fitting to fit for your compressor air line, the other hole, a fitting you can slip a vacuum line onto. all you do is: put a little oil on a rag, light it up, let it burn for a few seconds, then put I out, but let it "smolder". Put the rag in the can and put the lid on. Put the vacuum line onto a vacuum port on the intake of the engine, then connect air pressure to the air fitting on the lid. **** ONLY USE about 5 PSI of air pressure, or all you'll do is blow the lid off the can)***** the smoke will go through the engine and come Out Everywhere there is a Leak ! very simple, took me about 20 min to make. Hope that helps. feel free to post this if you want. [/QUOTE]
[/QUOTE] this may be a dumb question, but is there any certain vacuum line that yields the best results?
If you are having a 3000 RPM idle after taking off your throttle body there are only two places that can leak that much vacuum.
The first is the EGR tube.
The second is the IAC output passage O-ring located on the inside of throttle body where the IAC passage tube inserts into the TB.
The other possibility of a 3000 RPM idle is a stuck wide open IAC valve. Start the engine, cover the IAC input passage and see if the idle drops. The IAC passage input is that big hole at the bottom of the floor or the throttle body just outside the throttle valve. Take off the snorkel and cover it with your finger. If the idle drops then look at the IAC valve being stuck fully retracted. If the idle is still 3000 rpm then pull the TB back off, put the o-ring back in place in it's groove and reinstall the TB.
The o-ring is visible in the IAC output passage on the Fiero (right) throttle body.
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IAC input passage visible in this pic
[This message has been edited by phonedawgz (edited 09-22-2013).]
Originally posted by meet_my_grandma: and ogre, are you referring to this vacuum bubble thing I was asking about?
bubbles isn't a problem...
quote
Originally posted by meet_my_grandma: Use a shop vac with the hose installed at the other end, where it blows instead of sucks. Insert the hose in the tail pipe, and using duct tape seal it in.
That will blow air and rust, catalyst debris/guts, etc towards the engine. Any can get stuck in valves and/or between piston(s) and block. Exhaust valve is easy to burn w/o proper seal.
You may find vac leak and month(s) later the engine dies from a burnt valve, low pressure on a cyl from scratch cyl wall...
quote
Originally posted by Lou6t4gto: Better to just use a "Pressurized SMOKE CAN, cost about $2 to make.
Many ways to make something... likely even a Bee Smoker can work. Just don't use DIY methods in a garage etc... Burning most things causes health problems etc. Like Don't use oil... New and Old engine/trans/etc oil/grease are bad for health.
Maybe get smoke detector test smoke... This is a canned product. Example, CRC 02105 – Smoke Test® Brand Smoke Detector Tester CRC product maybe can change the top button to CRC 556 etc lubes or cleaners so you can get a straw then attach to vac tube/hose.
yep. it was the idle air tube. came loose. idle is back down! thanks for everyones imput!
**
now back to the main problem. intermittently, once warm, at stops or times i take it out of gear (its a 4 spd) my idle either idles out or comes very close to. while in motion, if I take my foot off the pedal or decrease my speed, I gurgle and backfire.
recent replacements- iac speed sensor tps
have done a vacuum smoke test as previously discussed and nothing was really found.
Also- I have a ticking during acceleration. last year a horrible shop in SC got their paws on it and "fixed" a crack in my exhaust manifold. this solved my ticking for awhile... best way to find this crack?
Best way to find the crack is to use a mechanics stethoscope, listen for changes in sound. Or just use a small diameter hose and run it along your manifolds listening for changes in sound. One end up to your ear, other to the suspected parts. first place to look for cracks is the firewall side manifold, second the y pipe at the joint, and third the trunk side manifold. For your other issue check the timing, just make sure to put it in diagnostic mode first.
Hope this helps
[This message has been edited by hiwil88formula (edited 09-24-2013).]
Best way to find the crack is to use a mechanics stethoscope, listen for changes in sound. Or just use a small diameter hose and run it along your manifolds listening for changes in sound. One end up to your ear, other to the suspected parts. first place to look for cracks is the firewall side manifold, second the y pipe at the joint, and third the trunk side manifold. For your other issue check the timing, just make sure to put it in diagnostic mode first.
Hope this helps
I like a section of old garden hose, 2 or 3' section, one end in your ear and the other move around the exhaust system, you will know right away as soon as you are near it, lots cheaper.
OLD SCHOOL RULES.
Steve
------------------ Technology is great when it works, and one big pain in the ass when it doesn't
Dk. Blue and Lt. Green wires? Reverse switch for the 5 speed. 4 speeds have the reverse switch in the console. 5 speeds have it on the tranny. Your wiring harness was built to support the coming 5 speed but your car didn't get it.
The connector is the temperature sender for the dash guage. You can either buy a new pigtail from the fiero stor for $25 or just the plastic thingy for $5 from rodney. You exhaust seems to be missing bolts, or you removed them before the picture. I think they sell exhaust doughnuts that should fit there. If you tighten the bolts enough you might not need a gasket there.
Bolts removed before pic. Now sealed and bolts Tightened. But everything is currently reconnected and the manifold closest to the trunk is smoking all over. Not sure if it's leftover from seafoaming, thought I got most out
guess its time to pull that all off
