HIGH IDLE SOLVED!!!!!!!!!! NOT VACUUM LINE ISSUE!!!

[blksmth88]

So i was under my car today to do some work and inspect some odds and ends when i discovered something interesting. first off my oil pressure sending unit or light unit was leaking so theres a common leak zone to check if you have an oil leak. But the real score of the day was finding a hole in the intake manifold.. yes a hole!! and guess what, beside this hole is another spot thats nearly a hole. what im assuming is from the factory this was a very thin spot in the casting material. if you have an older carbed model like mine and cant solve the flat spot in the torque range and seem to have a high idle for no reason with no obvious vacuum leaks then get under there and look up at the passenger or right side of the intake manifold you may have a small hole also. here is a pic of mine. i couldnt believe it. im waiting on some 2 part steel apoxy to dry now for this hole and the second thin spot to the right. good luck guys hopefully this helps some of you with high idle issues. id bet there are a lot of cars on the road that have this same hole and if not the hole i bet you can push one with a screw driver here. but dont obviously.

15181567_10207723299825779_7510974675105417973_n.jpg

[blksmth88]

no clue why that pic is so dark ill try to get another one thats easier too see. thats also bigger through photobucket

[FestYboy]

That hole is right at the egr passage...

[Flyin4stroke]

Crazy

[WmWatt]

Makes one wonder if something in the EGR gases ate through the manifold. Interesting to see how much gunk in the EGR valve.

[bravekozak]

Wowser! It makes me glad that I am not running the stock carb manifold.
I will have to check that out. It is possible that that could have been a one time only bad casting from a bad or shifted core.

[Dragonhealer]

Excelent work!
I also wonder about that toxic corrosive crap that goes through the EGR...

[greaseyfingers]

So i was under my car today to do some work and inspect some odds and ends when i discovered something interesting. first off my oil pressure sending unit or light unit was leaking so theres a common leak zone to check if you have an oil leak. But the real score of the day was finding a hole in the intake manifold.. yes a hole!! and guess what, beside this hole is another spot thats nearly a hole. what im assuming is from the factory this was a very thin spot in the casting material. if you have an older carbed model like mine and cant solve the flat spot in the torque range and seem to have a high idle for no reason with no obvious vacuum leaks then get under there and look up at the passenger or right side of the intake manifold you may have a small hole also. here is a pic of mine. i couldnt believe it. im waiting on some 2 part steel apoxy to dry now for this hole and the second thin spot to the right. good luck guys hopefully this helps some of you with high idle issues. id bet there are a lot of cars on the road that have this same hole and if not the hole i bet you can push one with a screw driver here. but dont obviously.

[ATTACH=CONFIG]20237[/ATTACH]

Is the oil pressure sending unit located, somewhere, above the oil filter?? Does the oil filter need to be removed to replace it, and what size wrench or socket is needed to do this??
Is it common for oil to, also, leak from around the distributor o-ring, and how many miles on a Festiva does it usually take, before this happens??
My 91 Festiva is still slowly leaking oil from, somewhere, after the valve cover gasket was replaced, when I, also, replaced the crankshaft seal, at the same time a new timing belt was installed..

[TominMO]

1. Is the oil pressure sending unit located, somewhere, above the oil filter??
2. Does the oil filter need to be removed to replace it, and what size wrench or socket is needed to do this??
3. Is it common for oil to, also, leak from around the distributor o-ring, and how many miles on a Festiva does it usually take, before this happens??
My 91 Festiva is still slowly leaking oil from, somewhere, after the valve cover gasket was replaced, when I, also, replaced the crankshaft seal, at the same time a new timing belt was installed..

Welcome to the Forum!

1. Yes, above and to the right if you are looking from under the car.
2. Yeah the oil filter will have to be removed. You will have to see for yourself what size wrench is needed on the sending unit.
3. Yes on the disty o-ring. Replacing it (and the O2 sensor) should IMO be done with every major tuneup, say 50K miles or so. And plug wires every 100K, i.e. every other major tuneup.

Another common leak point is the camshaft seal, and luckily is easier to replace than the crank seal. Exact same seal I believe.

Why do you want to remove the oil sending unit BTW? If the reason is oil leaking, then remove it and use blue Loc-tite or bearing grease on the threads when you re-install, to block the oil.

[lessersivad]

Good job on finding the hole in the intake.

You probably could have at least found the area a bit quicker using carb or brake cleaner. Spraying different areas until you heard a definite change/drop in the idle. THEN start investigating the spot(s) where you heard the difference.

[greaseyfingers]

Welcome to the Forum!

1. Yes, above and to the right if you are looking from under the car.
2. Yeah the oil filter will have to be removed. You will have to see for yourself what size wrench is needed on the sending unit.
3. Yes on the disty o-ring. Replacing it (and the O2 sensor) should IMO be done with every major tuneup, say 50K miles or so. And plug wires every 100K, i.e. every other major tuneup.


Another common leak point is the camshaft seal, and luckily is easier to replace than the crank seal. Exact same seal I believe.

Why do you want to remove the oil sending unit BTW? If the reason is oil leaking, then remove it and use blue Loc-tite or bearing grease on the threads when you re-install, to block the oil.

Doesn't a car's oil sending unit, usually, leak past the spring loaded diaphram from inside the oil sending unit's housing to it's outside, when they start leaking??

[TominMO]

Doesn't a car's oil sending unit, usually, leak past the spring loaded diaphram from inside the oil sending unit's housing to it's outside, when they start leaking??

Beats me. I thought it was an electrical connection, like on water temp sensors.

[william]

Your intake looks like mine but mine dosnt leak.
Its a very thin spot in casting.


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[william]

Sent from my SAMSUNG-SM-G900A using Tapatalk

[HobowithaFestiva]

So I’m checking for this hole and I do not see what I am looking for I have a 88 Festy and I’ve 244k on it but she runs so good I currently can’t get my idle under 1300 to quiet her down so they’ll at least try to smog it.