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Topic: Looking for help with mystery diagnosis... (Read 3366 times) previous topic - next topic

Looking for help with mystery diagnosis...

Reply #15 –
First of all, I want to thank you guys for taking the time to help me out on this thread.  I think that is really cool.  I can tell you already care more than some of the techs at some shops I've gone to, haha.  The problem is I am by no means a mechanic, and a lot of this work I can't do myself.  I have one of those Haynes Manuals for Cougars and T Birds, but not a lot of knowledge or experience working on engines and certainly not any tools other than wrenches.  I've been at the mercy of repair shops through this ordeal... but I do feel there is some of these things I can check myself.  I do think I'm capable of taking the throttle body off and checking it out.  I pulled the vacuum line off the EGR yesterday.  The line looked OK but there did not seem to be much vacuum coming from it.  Is this supposed to be constant?  And would you be able to feel the vacuum by putting your thumb over the end of the hose with the motor running?  Jcassity, I will check out your DIY stuff for sure, and just FYI the converter is brand new as that was one of the things I had replaced during what I will now just dub "the Era of Repair."

Looking for help with mystery diagnosis...

Reply #17 –
Ahhhh.  If I plug it and go for a drive like you said, what do I look for?

Looking for help with mystery diagnosis...

Reply #19 –
Haha, right on.  I'll try that out today.

Looking for help with mystery diagnosis...

Reply #20 –
sounds like the shop thats been working on the car basically shot gun trouble shot.
i would suggest you put put the car in the hands of someone you know fiddles with cars and have him/her log in under your user name/password and then we can get that person to troubleshoot.

Im  blown away with all the parts replaced when at the end of the day, there is one thing missing on this thread and that is the original diagnosis.
a car needs battery power, fuel, spark, air, sealed coolant system, sealed combustion system. you were missing one or more of these and that was never told to you.

if you want to take on this, we can do one step at a time but you will have to buy certain testing tools which are going to be useful on other cars you own later.

either way, if you cant then this thread is going nowhere and we mean well,
first thing you should be doing is running the codes, i know you have a paper clip lying around.

this is a CFI motor and its layout is very different from "most all" the cars on this board which are 5.0's.

Looking for help with mystery diagnosis...

Reply #21 –
Quote from: TheFoeYouKnow;400744
You want to make sure the spacer gasket under the throttling isn't leaking her into the intake.

 
cracked CFI gasket either under the CFI or under the EGR plate "should" induce a high idle condition.... thats not happening from what im reading.  basically a vac leak.

Looking for help with mystery diagnosis...

Reply #22 –
here is a few easy tests that i think you would be able to do

a test you can do
-add water to a spray bottle and wait till night time, unless you have a garage you can "make dark"
-spray water mist along spark plug wires
~if you find spark jumping off some wires let us know... dont forget to mist spray the coil as well.

another test you can do
-with a cressent wrench, undo the rear passanger side fuel "input line"
-find your computer test connector and locate the "tan / light green wire"
-remove 1'' of insulation off both ends of a scap piece of 2' or so long wire
-stuff one end of the s wire in the computer test connector on the pin for the tan light green.
-attach the other end of the wire to the car body to get a ground
-find a gas can or empty milk jug.
-stick your fuel line in the milk jug or container and secure
-turn on your ignition switch to run only , dont start
-the fuel will be delivered to your container ****very quickly*****

basically that fuel line should shoot fuel out a clear across the engine bay or about 5 or six feed.
if the fuel comes out "limp" like its going about a foot or so before it archs downward, the fuel pump is weak.
the computer will notice weak fuel pressure and try to richen things up in order to run.

============================
next test you can do..............
visually inspect the idle motor controllers activity like i described.  you have to remove the air cleaner then stuff a bolt or something in each vac line to temp delete the air cleaner.

----------------------------------------
next test you can do
-with a warmed up motor, remove the belt.(notice i say warm,, not hot,, just warm as in when the temp needle starts to move.
-just start car and let it run for about 3 minute2 and then remove the belt.,, theres a reason for this.....as follows.
-drive car up / down driveway with no belt and simulate see if it acts the same.

what you have to do is be quick to remove the belt after it is warm to perform this test so i think you need to have your tools ready and "know" how to remove the belt in advance.
what we are doing is testing to see if the smog pump may be binding up when warm and thats causing the engine to stumble.

===========================
another test you can do
-unhook exhaust Y pipes where they come off the engine and combine as one pipe "entering" the catalytic converter.
-run car with this exhaust section separated.. loosen nuts,, shove something up between the connection to open it up about 1''.
-this will allow exhaust to temp bypass the rest of the exhaust system
~this may be difficult for you to do and the bolting hardware may need cleaned off or it may even just break off if you attempt to loosen.

===========================
another test you can do
-buy a can of carberator cleaner.
-with engine at idle, and all things bolted back on ,, nothing removed like air cleaner and such,,, spray carb cleaner in the following areas:
-spray behing the coolant fill tank=this is where all your vac control solenoids are
-spray along the wire loom that containes your vac lines along the cars fire wall (will consist of a Tan, Black, Green, Red, orange vac lines.)
spray inside the split of the wire loom if you can in various areas.
-spray along the area where the CFI bolts to the engine
~listen for a  change in engine rpm and if so, you are finding a vac leak somewhere.

===========================
another test you can do
-do the spark test i described earler

Looking for help with mystery diagnosis...

Reply #23 –
Dude, you would be disappointed in humanity if you knew what I went through with shops trying to get this car fixed.  It went through four different repair shops, and exhaust shop, one independent guy and six months of hell to get where I'm at now.  That's why I'm here trying to get some help.  Everything was fine until one day it died on the highway coming to a stop and would not restart.  At that point, I towed it to the shop I had taken it to for a few previous repairs, tires etc.  Those guys had it for three weeks before they finally threw in the towel and told me it needed a new motor.  Now I'm not a genius, but I did do some QC work at a dealership and I've never heard of any car running just fine for years as a daily driver and then one day all of a sudden the motor goes bad and that's that.  So at that point I spoke with my brother who is fairly in the know about Cougars as he has had three, and he talked to his mechanic buddy who used to own a Ford dealership who suggested checking out the timing gears as they were apparently made of nylon and would wear out right around 85,000 - 90,000 miles.  Armed with this knowledge, I took it to said independent guy who found that indeed the teeth were worn way down on the cam sprocket I believe, so that was replaced and the timing reset.  Now I went to this guy per recommendation from a buddy at work, but I would label him a backyard mechanic who caused as much hassle as he fixed.  He set the timing too low on top of leaving bolts loose in the crankcase... so that led me to another shop.  These guys were the parts throwers.  They did find some vacuum leaks that were fixed so my heater controls would work again, and they did the majority of work listed in my initial post... on top of redoing the entire timing job again because the backyard mechanic guy left the two bolts that anchor the cam sprocket loose.  You could slide it back and forth a good inch, inch and a half... not to mention he didn't get a gasket for the job, he just sealed the crankcase up with some sort of epoxy.  It was great.  Anyways, after a couple of months dealing with the parts throwing shop fixing some issues, and trying to diagnose others that were supposedly part of the problem then doing work that didn't change anything, I took it to another shop.  This was the best luck I had, and where the EGR, ISC motor, thermostat and 02 sensors were replaced.  Now, during the course of all of these shops visits and repair work, that is where the rich exhaust odor came from.  It did not have this problem prior to the whole ordeal... so either it is a result of faulty work on somebody's part I'm guessing, or it's a problem that developed after having something replaced.  The car has been sitting since June as I worked at a radio station and had transportation provided to me via an endorsp00get.  Well that is over now and I am reviving my dear Cougar once again.  I have only taken it on a couple of short trips in the past few days as the brakes need to be bled and the system refilled before I get too carried away, but it seemed to run OK aside from a couple of weird instances after I drove it for a few minutes and parked it, let it idle and the idle kicked up significantly but only momentarily then kicked back down to a normal rpm.  It does still have a rich exhaust odor upon start up, but it also seems to kind of come and go as it idles... but always present upon start up.  That's where I sit with this beast as of right now.  It's got 99,000 miles on it and seemingly plenty of good days ahead if I can just pinpoint what the hell happened.

Aren't you glad you know how to work on your own cars?

Looking for help with mystery diagnosis...

Reply #24 –
I am still on post 1 becasue this is the issue(s) you have currently,, correct?

Quote from: Jesse Adams;400731

The car is running very rich, with a very pungent exhaust odor when it's started up, idling and while driving.  My MPG is very poor and the car stumbles and dies while coming to stops after you drive it for a few minutes and the engine gets warm.  ?



-incorrect 02 sensor
-low fuel presure
-poor spark delivery (pick up or stator assembly down inside the distributor, not the module on the side
-poor compression


I see in your write up that the one guy did not tighten the cam thrust bearing down,, god only knows how much damage that caused, maybe none since the cam will thrust to the rear of the engine during operation,, so you may luck out in that area.

Looking for help with mystery diagnosis...

Reply #25 –
J, I think you're going the wrong way, but there are only 2 of the possibles you listed that I can logically eliminate for you. Since his problem persists while driving, we can eliminate the EGOs s they're not part of the fuel calculation above hi idle, and low fuel pressure, which you can easily eliminate as the cause of a rich running condition.  A deficit of fuel isn't going to make the engine use more fuel.  Having said that, I do believe there is a fueling problem afoot here.  Poor compression and ignition problems remain a possible cause, but I can't imagine the odds are high.

Looking for help with mystery diagnosis...

Reply #26 –
I don't have much experience with Ford CFI, but if it me the first place I'd be looking with symptoms like that is the engine coolant temperature sensor (ECT sensor). If that sensor is bad, has a poor connection, or if the wiring between it and the computer is bad, it will trick the computer into thinking the engine is colder than it really is, and it will run pig rich. Again, I ain't a CFI expert, but any fuel injection system relies on the input from the ECT. It's one of the most important and overlooked sensors in an EFI system...
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Looking for help with mystery diagnosis...

Reply #27 –
J, yes those are the symptoms currently... but the dying while coming to stops is somewhat intermittent.  It doesn't die at every stop.  I will be able to check/test some more things out in the next couple of days.  And Thunder Chicken, I am definitely going to look into that.

Looking for help with mystery diagnosis...

Reply #28 –
I do have some input but will refrain until all of the above avenues are explored. Cover the basics first. If you're still stuck, I have the likely solution but it is a last resort.

Looking for help with mystery diagnosis...

Reply #29 –
OK so today I got a chance to check some things out and take the Cougar for a couple of real drives.  Foe, I took a drive with the vacuum line to the EGR plugged and overall it did not seem to make a difference, although I do feel like the motor seemed a bit more responsive.  Everything down around the throttle bottle looks good far as I can tell... no leaks.  I remember now when the car was at the first shop, they mentioned they had replaced a gasket in the throttle body but never specified which one.  I think they had it off checking the fuel pressure if I remember correctly, and also stating that at some point a fuel stream shot up into the air when checking for this which seemed to surprise them.  I also seem to remember them pressure testing the cylinders which checked out OK as well... but remember these are the guys that never thought to check the timing and diagnosed a bad motor.

Thunder Chicken, your post intrigued me due to the fact that the thermostat was replaced, so I inspected the coolant temp sending unit and definitely found some less than stellar wiring at the connector.  There is about 3/8 exposed wire at the base of the connector which has been unprotected long enough to where it looks old and brown.  I definitely feel I should get the connector replaced, and the sending unit is like 8 bucks so I'm going to replace that also.  Maybe this will help with the rich condition?  I can tell the mileage is still poor after driving it a couple of days.

When driving it today it seems something is robbing the motor of it's power.  I noticed today when pulling out onto the hiway and accelerating I could feel a drop in power right after it shifted into second gear.  It's strange, like you can just feel the whole motor bog down.  Would this be a condition of being fed too much fuel?  Also, when driving at a constant hiway speed at times it does this weird little stutter/surge thing... almost like there is this split second drop in power or fuel supply or something that feels like a brief stutter when driving it that goes on and off.  This happens upon acceleration as well, and seems to prevent the car from shifting into third sometimes.  It almost acts like something is clogged.  Does that make any sense?

I definitely have a paper clip, so I'm going to try this pulling codes with a paper clip thing... but I'll have to look the instructions over a bit, to me it seems sort of complicated.