I had the booster (original with 225K) replaced last week, the hissing is gone and when I

pump the brakes the idle speed does not increase like it did before but, the minor rough

idle is still there. I was hoping that would go away.

Im thinking either timing chain, pip sensor, fouled plug or vacuum leak.

Im not sure I want to mess with it, It just passed smog so it might be nothing worth investigating.

What do you all think?

 

Ah yes, with age, you keep replacing items till it runs right, you got one down, if it were newer with Mass Air I'd suggest looking at a filter intake leak, you may want to have your TPS checked, it can be tested with a multi-meter, I don't know the correct voltage but you can find it on the internet.

 

I think if it were the TPS I would be getting some other wierd things happening but thats something to keep in mind. My year doesnt have a MAF but it does have a MAP, maybe thats a problem. I will have to find out how to test that, if there is one.

Thanks.

 

After quickly checking out the symptoms of a bad or failing map sensor, I dont think thats it. They seem to be very severe and obvious.

 

check the easy stuff first
plugs, wires etc.....

 

Yea, I had them changed out about 5 years ago, It may be longer I dont remember exactly. Maybe I will have them done again to rule out a bad plug or wire.
What is strange is that a few years ago when I changed out the Ignition Control module, the cap, rotor and ignition coil (all at the same time) it ran the best its ever ran for about a week, then it developed this minor rough idle.

 

AAAARRRRGGG.........

Today on the way home it started to idle rougher than usual and it almost stalled out when I started it up at the market...But the last few days we had a heat wave, and it usually does that when hotter than usual.

I am also wondering If I installed the correct Ignition control module.


What would be the symptoms of installing the wrong one?

 

Got the plugs and wires done today, MC plugs and the Ford racing wires that were mentioned in a thread here.

Runs smoother and noticeably more power. None of the plugs were fouled or looked bad at all, one plug had the electrode slightly offset (had to have been installed like that) but even that one didnt look bad. They have not been replaced in a long time.

I also had to replace the Coil because the clip broke that holds the wire on, I told the mechanic I would replace it myself, when I pulled the new wire off, the electrode on the coil came off . Used gorilla tape to hold the wire on the coil and drove to oreilly`s just about 2 blocks away and picked up a new coil and found out the clip does not come with the coil Anyway...... The wire holds on fine snapped onto the new coil without the clip.
It does run smoother but there still is a slight rough idle, But what the hell.... It just crossed over 226,000 miles last week.