1984 T-Bird 5.0 EEC-III (one of those "special" California 1984 5.0's with the EEC-III system). Just wanna give the "your number one" salute to Ford and California for that "special" honor grrrrr....anyways.....
The car went in for its smog and of course, it failed. HC at on the 50/15 test and high NOx on the 50/15 and 25/15 dyno tests.
So I spent some bucks on it....plugs, wires, coil, cap/rotor, air filter, a bottle of seafoam, and a oil change. Played with the vacuum switches under the coolant bottle and got the egr to work (had no vacuum) and throttle kicker/dashpot did not have any vacuum ( so that works now too). Which helped with the idle speed with the a/c on.
So took it back over today, the NOX dropped down, the CO2 levels were awesome, the CO levels were good....but HC still too high. The smog tech pulled the coil wire, and cranked it. The HC pegged the machine at 10,000 ppm which he said indicated that the cats were dead (cats were replaced 2 years ago).
The other PITA problem that has been driving me nuts is the idle. It will start up cold and idle great. It will run on the highway great. You come off the highway, and come to a stop.....it will die. Starts right back up and idles fine. Go the next light it will be fine......or it will die...you never know what mood its gonna be in. Sometimes when it dies, it will just crank and fire. Other times, you have to open the throttle before it will start, and then run.
Example today.....started up...ran fine for 45 miles on the freeway, got off...died. Restart...went to the next two lights it was fine. Sat for 45 min. Start it up...dies. Restart...dies. Restart...idle low...dies. Restart...hold pedal and brake..runs..get on the freeway for 40 mile drive....runs great. Get off...dies...restart..dies (does this 5 times). Finally hold the pedal and brake..for about 2 miles of city driving. Car sits for 20 min at destination. Start it up, starts and idles...but like ....then just shuts off in park. Restart and let idle...for about 2 min...then just dies. Restart and get on the freeway, runs great 20 mile drive. Get off idles wonderful, goes two stop lights and waiting for the light to turn green, its idle quality gets worst til it just dies, restarts easy. Talked to some people, said its the ignition module, so I replaced it this afternoon.
Took it out to dinner tonight, idle not that smooth, and died twice.
WTF!!!! Some times it idles awesome, other times...like , other times...it will idle like and then the rpm drops lower and lower till it dies, and then other times it will idle fine and just die like flipping a switch.
So....new plugs, wires, cap/rotor, egr position sensor, ignition module. The tps tested out at 1.96v at idle, and seems linear as I moved it open on the DVOM.
Running out of ideas. The state will give me $1000 bucks to hand the car over to them, but I like the car and have waaaaaaaaaaaaaaaaaaaayyyyyyyyy tooooooooo much time invested in the car to just give up on it now. Plus, the car is kinda cool :D
Any ideas?????
On my 5.0 EFI car, the tps should be 1.0 volt or LESS at idle.
Keep in mind that it's a EEC3 system, so it runs a 9v reference voltage.
wow can't belive they still test you out by me anything older then i think 97 is exempt
1975 and older are exempt. It uses to be 30 years and older were exempt.
Well I got it to read codes today, had a code for the coolant temp sensor and the egr position sensor. The egr position sensor is new, so there is probably some crud in the valve. Picked up a new CTS today, put it in tomorrow.
It started up this am and ran like a million bucks. As it warmed up, the idle quality dropped and then it started its random shutdowns B.S.
Such a simple system, yet such a PITA to get and info on it and work on.
Put the temp sensor in.....same code. Pulled the egr and the sensor, both clear. At wits end with this eec3 madness.
Read this thread.
http://www.foxtbirdcougarforums.com/showthread.php?31660-Idle-Surge-1984-5.0-Thunderbird-CFI-EEC-III-Duraspark-III
I've replaced the ignition module, and same thing. Mine isn't so much a surge, but more that the idle drops (almost like a misfire) here and there and sometimes, it dies like turning the key off. It's died while running the self test and the PCM is still flashing codes back.
Update.....
So after replacing.....
Cap/Rotor
Coil
Plugs
Wires
02 Sensor
TPS
Ignition Module
Coolant Temp Sensor
MAP/Baro Sensor
Cleaned the Intake Air Temp Sensor
Bottle of Seafoam
and fuel pressure is at 41psi
Disconnected the purge solenoid to clean it out....its "was" good...until I broke the nipple off of it. So i have the port on the TB base capped off for right now.
Its idles like a total POS.
It starts up and idles fine. About 30sec-1min later it starts it BS. You can watch the idle kicker and the Choke Pulloff drop out and back on when it does its idle drop. The 02 sensor voltage goes up (rich) when it hiccups. In park, it idles but still does it just barely. Put it in drive, and it starts to out. Turn on the A/C...and it gets worse whenever the compressor turns on.
There is like literally nothing left to swap out. No vacuum leaks that I can see or hear. The idle has been set and reset and reset following the emissions label procedures and just good ol' "it close enough" procedures.....same result.
It starts up cold perfectly, it warm starts perfectly.....until after that 30 sec window.
I have disconnecting the egr vacuum line same thing....
Unplugging any of the sensors and the car dies.....so their working.
The only codes that this remedial PCM gives me is ECT shorted or out of range and EGR Position shorted/out of range. Yet both have been replaced and the EGR valve was taken off, didn't see anything wrong.
Whats the up with it? Anything....I mean anything else you guys and can think of?
Check voltage on your tps, make sure no deadspots. My TC did same thing with random dying at stop lights and idle issues.
The tps is brand new as in less than 24 hours old. Same issue with new and old tps.
Pull the connector off the ECT and check the voltage on the two wires.
With the key on:
The Signal Return, black/white wire to EEC pin 19 should have close to 0 volts.
The ECT, light green/yellow wire to EEC pin 21 should have close to 9 volts. (I think)
I think you should try to find out why the EEC is detecting an ECT sensor problem. That's why I suggested checking the voltages above.
The voltages were correct.
After letting it run, for a while, t would idle down to about 350rpm for a while dead smooth with the a/c on....then back up to 550rpm perfect.....then do its hiccup stuff and/or die. If it dies, you have to open the throttle a little to get it to restart, or it will just crank.
It only does its BS once it warm, and only after about 2 min after it restarts.
Does the exhaust smoke a little when you restart after it stalls? Having to open the throttle to restart sounds like it is flooded.
On the ECT, I should have told you to check the voltage between the two wires to make sure the signal return is not an open circuit. That is put the red meter lead on one wire and the black meter lead on the other wire.
When it does the hiccup, the 02 sensor voltage shoots up (0.7volts and above).....so it goes rich when it runs like . So then I go crank it, no start. So then you have to open the thottle to start it, and some of time it will shoot a flame up the TB when it fires.
I did put the leads between the sensor leads, the voltage was lower.....i want to say about low 7volts. When it was wire lead to battery....it was about 7.8volts.
I appreciate your help.
Does it have a spout? If so take it out, sounds like your timing is jacked with backfiring out the TB.
Does this have the "brain box" on the fender? If so check that guy.
No spout. It's EEC-III. Timing is not adjustable. Has a crank sensor that feeds the ignition module.
Yes it has the ignition module on the fender, even that was replaced.
When it stalls, check to see if one of the injectors is dripping fuel, not sealing.
Try running with one injector unplugged then the other unplugged.
Funny that you said that....
I did that too last week....it runs but barely/rough on one injector at a time....and both sides seems the same roughness.
Where is the pcm located and how do you get it out?
Can you remove the injectors with the TB on the car? What's the trick to remove the injector from the rail/TB?
On the EEC IV the EEC is behind the passenger side kick panel.
Never done it, but pretty sure you have remove TB.
Sounds to me like it's going nuts when it goes to closed loop, just for grins disconnect the O2 sensor and see if that changes anything... At 27 years old the computer may well have a issue, I had bad capacitors in my '93 Lightning PCM that made it go nuts(which I replaced and it's fixed)... Still I would not replace the ECM till all the other possibilities were covered...
One more thing, you mentioned the idle dropped with the A/C on, sounds like the ECM isn't sending a signal to the idle motor to increase speed...
That's exactly my thought that is going on. The question is why it's going nuts.
The car doesn't have a idle motor, just this vacuum kicker/dashpot. When it starts going nuts, you see the kicker and the fast idle pulloff (their are both controlled by the same solenoid and same line) kick out and then back.
The only thing not replaced at this point is the crankshaft sensor and that's because it's a major undertaking (remove alt, smog pump, it's bracket and everything else associated with it)
There is 83 eec3 car at the pick a part, so a PCM would be cheap. But how do I get it out/location?
The ECM should be in the passenger side kick panel(the IV are there)... Probably will be a support bracket that has to be loosened, also the electrical connector will have to be removed before it will slide out...
Swapped in a different ECM...........same thing.
Was playing around with the ECT, and it looks likes runs better with it unplugged. Sometimes it will start with it unplugged, other times it has to be plugged in to start. If its running and you unplug the ECT, it will sometimes die or I can plug it right back in and unplug it....then it will run.
Watching the 02, it running at .1-.2v, then will hiccup and it goes to .7-.9v at idle.
No wonder why the techs used to call these cars "run-away cars".....
IT PASSED!!!!!!!
The numbers were flat out awesome....flew right through the dyno smog test. 37 HC 0.01% CO 277 NoX
Then while idling....it died. Had not died in three days, just the hiccup and lowering idle. While I was there talked to a old school ford mechanic who thought it could be fuel pressure regulator maybe malfuctioning.
So half the saga is done.....
So I spent all day f-ing with this car.
Changed the fuel filter.....no better. Ohm checked each of the solenoids.....all in spec. I double checked the ect and act. Swapped map sensors back and forth. Egr position sensors swapped for old and back to new.
I give up.
change the crank sensor if its one of the last things left, if its bad it would explain why the motor loads up with fuel, the spark cuts out and loads the exhaust - o2 spike at stall
I see the wire going to the sensor.
Looks like the alt, air pump, etc needs to be removed to get to it. Is there a shortcut/access to the sensor that I am not seeing?
Son of a beatch!!!!!
It was acting stupid today (like it has been). I by accident moved the coil wire and it stopped its bs.
The coil wire was very close and touching the wires for the injectors and the tps. Put the wires near each other.....hiccup. Move the coil wire away.....purrrrrrrs :=)
So now the coil wire runs on top of the air cleaner snout and the injector/tps wires are under and to the back of the snout. I guess the rf from the coil wire was screwing with the injector or tps wire voltages. Brand new Accel plug wires should shield better than that I would guess, maybe not.
Gonna drive for the next few days and see what it does......let my 4.6 rest a few days.
Great find!!!
I'm going to write that on the wall for future reference.
Rule of thumb with old fords is to just run motorcraft wires. Fords get pissy with non motorcraft parts. Good find though man, it's a pain in the rear to find out that it was something simple after you have been fighting for so long. Also, a good way to drop those Hydro carbons is to throw a couple of gallons of Methanol in your gas tank. I have a 93 ranger that did great on CO and CO2 but failed for 374 in Hydrocarbons, after 4 gallons of Methanol to 10 gallons of premium it passed with 62 in the hydrocarbons. :)
....and now today the passenger side window doesn't want to go down or up....you can hear the motor...but its going crooked. Always something....lol