Engine idle issue's.

[FestYboy]

valelo, i wouldn;t bother with that TPS... will only bring more headache.

[miami man]

i have the same problem with mine and i am going to see if the iac is stuck and i even got two extra ones from the junkyard

[miami man]

i have had a post in the past about the same problem

[WeDefyU]

To check your IAC remove it, blow through the air side and note the resistance to airflow, then get hot water running in your faucet and let in run through the coolant side of your IAC. The resistance to airflow should be reduced. To check the electrical part just apply 12 volts to the electrical connections and there should be no resistance to airflow, also you should here a click when voltage is applied.

[WeDefyU]

Have you replaced the coolant sensor in the intake yet? Fords notoriously can run very poor because of this?

[valelotax]

So, today the issue is known. LOW COMPRESSION. number 1 has 30psi, number 2 has 0psi, number 3 has 120psi, number 4 has 90psi. A friend of our's said a rebuilt engine should have about 145psi of compression, but mine doesn't. So tomorrow after school, the head will come off, and I'll turn the cam, and fill the valve's up with gas, oil, water, or whatever and see if it'll hold any. Or blast air through it, but I'm getting sick and tired of this motor; it's costing us more than just getting a BP and dropping it in. UUUUUHHHHHH.

[Movin]

Just because the compression is wacky doesn't mean for sure the engine is bad.
You would need to decarbon the rings , run it then recheck.

It sounds like you need to figure out if awesome mileage with good power or
awesome power with good mileage is most important to you. Then fix it the way
you want it !

[valelotax]

You're right, but, I rebuilt the engine, and I had a friend clean the piston's and rod's. NOT a single spec of carbon on them, and I also ran a small screw driver, careful not to damage anything, to make sure there was no carbon. And, all the ring's were set a 1/4 turn from each other so none of the ring "gap's" lined up. I checked, double-checked, and triple-checked, before I ever set them piston's in. But, it would't hurt to check them out again. Just in case...

It just get's frustrating seeing something you built, start acting up.

[FestYboy]

low numbers like that point to blown fire rings OR burnt valves...

[Movin]

Yeah if those are cleaned up parts it would not hurt to take a quick look
with a boroscope. It might be more cost effective to get your bp !!
You have free labor, right ?

[valelotax]

Free labor? Like access to machine's? The head will be coming off today after school and maybe the piston's will be out. Only have 4 hour's of work before it get's dark.

If it's valve's, drop new engine in. But, if it's ring's I'll maybe replace them just to see if that's what it was.

[FestYboy]

why not replace the valves if that's the issue? that's what i'm doing...

[valelotax]

Well FestYboy, and anyone else, I didn't get the head off today but, I'm trying to find out exactly what the problem is BEFORE I go tearing thing's apart. A family friend said a good way to see if the ring's or the valve's are bad is to take the valve cover off, take a spark plug (whichever cylinder you are testing) out and hook up a air compressor (via air blower) where the spark plug goes, and pump air into the cylinder. If it come's out the oil dipstick it's ring's, if it come's out one of the valve's or throttle body it's a valve issue. I did this using the compression tester gauge adapter (part you screw into the spark plug hole) and at the end of the adapter I put a piece of vacuum hose and then placed the blower on the end of the hose. Turned on the air and it leaked out of the throttle body, but I believe it was on the intake stroke, duh me . So, first thing tomorrow after school I'm putting it in TDC and repeating this test on all four cylinder's.

So my question is.... is this test ^ accurate enough to say I have a bad head, when done right of course.

Another thing I noticed is that only three rocker's squirt oil. Are all eight supposed to squirt oil out of the little small hole at the top of the arm? Could bad HLA's be the cause of all these problem's? (< though I doubt it)

And the thing about replacing the valve(s) like you said FestYboy, is I probably will get them done by a professional, seeing as though I have never done a head rebuild, but I do have a J-body head that I could practice on.... and I need my car to run.

[FestYboy]

ok yeah that test is A way to do it, though i would regulate the pressure down to ~ 100psi and make sure you keep the crank still... if it's off TDC the crank will want to spin on you and that can hurt you, so be careful!!!! also be prepaired to hear air form other cylinders (indicative of bad head gasket), this means that you have to have all the plugs out at the same time...

as far as the rockers: they should all be squirting oil. some super clean and an ultrasonic cleaner will put you right back in the game.

valves are easy, just gotta make sure the seat wasn't damaged and you can do that by lapping another valve lightly into that seat and see if there's any misses along the seat area. if you see seat damage, then a machine shop needs to come into the picture to fix the issue, then just lapp the valves back in and you're up and running.

read this as well, it might give you ideas (better pix comming soon): http://www.fordfestiva.com/forums/sh...ad+head+gasket