Low idle on 1981 TBI Lincoln Continential Towncar
Asked by migration_VoltaireT Oct 25, 2013 at 09:36 PM about the 1981 Lincoln Continental
Question type: Maintenance & Repair
I finally managed to get my 1981 Lincoln Continental MKVI running, albeit with an issue. She
runs and sounds great when im physically depressing the pedal, as soon as i let go she
sputters and dies.
Its been at least 4 months since she ran last, i replaced the water pump, starter solenoid,
voltage regulator, fuel filter, new oil, plugs+wires+cap, ignition coil, accelerator cable. She
also spews a substantial amount of white smoke since.
26 Answers
migration_VoltaireT answered 11 years ago
My guess is an idle problem? Im not sure hot to mess around with the adjustment on these TBI models tho, any help
migration_judge_roy answered 11 years ago
...well the throttle.....the computer keeps pointing to the distributor....have you got a vacuum advance on the distributor...this one has a diaphragm and pulls the throttle open if the hose has not fallen off or the diaphragm is torn~ take a look to see if I'm right....vacuum advance causing idle speed reduction~
migration_judge_roy answered 11 years ago
this ole fashioned distributor can simply be turned to increase idle speed and ignition timing...go too far and you'll have detonation and knockin' on acceleration~ perhaps 7 degrees btc if you've a timing light....these ole boys are old school~ check the numbers to make sure I ain't shittin' ya~
Sounds like a throttle position sensor issue.
migration_VoltaireT answered 11 years ago
Ford EEC III, non vacuum advance distributor. Its nonadjustable. The distributor itself comes striaght out of the block with the only connections being the wires. I have checked the throttle position sensor, ive advanced it but she still ends up dieing out, so i changed it back. I rebuilt the TBI assembly some 2 months ago FYI
Most throttle position sensors send a reference signal to the computer. Signal range is normally .5 volts at idle to 4.5-5 volts at full throttle. Just advancing it will not determine if it is the issue. What is the voltage of the reference signal it is sending while it is idling or in your case with key in run position but not running (should be .5 volts) And as you move the throttle to full open does the signal voltage smoothly climb to 4.5 volts at full throttle and smoothly go back to .5 volts when you return it to the idle position? If not replace the sensor.
Most have three wires going to them. One is the constant power supply and will not change voltage, one is a system ground and the other will be the reference wire going back to the system and will be the one you will need to check for the proper signal voltage.
migration_judge_roy answered 11 years ago
1981 technology...quite certain that it ain't all that advanced~ the fact that the computer was integrated at all is quite the shocker to me~
migration_judge_roy answered 11 years ago
if this is a California smogger, the EGR is supposed to engage on deceleration...perhaps yours is not...or engaging on acceleration as well...check the operation of this EGR valve (if you've got one) disassemble and clean with some brake cleaner or paint thinner~
migration_judge_roy answered 11 years ago
...still trying to wrap my head around the computer controlling the spark with a non-adjustable distributor....something is rotten in denmark with this concept~Computers DO not handle high-voltage timing well....coil packs above each sparkplug fixed all that~
migration_VoltaireT answered 11 years ago
It is at .223 when key is on position. When she trys to start it jumps up to .66. Ill see if it rises or changes any once i get her started again.
If you talking about the throttle position sensor. It does not have to be running to fully check it out. Best to just check with it not running and key in on position. Just manually move throttle with hand as you watch the voltage on your tester. The voltage should only change with the moving of the throttle and it should be a smooth climb up and down in relation to the position of the throttle.
migration_judge_roy answered 11 years ago
has a cable leading to the tps...on the tbi~guess these newfangled 'lectronics were about like the "flux capacitor" the Delorean used...at least as mysterious in a 1981 world~
migration_VoltaireT answered 11 years ago
3.6 at idle and climbs slowly to 7.00 full throttle. So ive got to replace it then?
migration_judge_roy answered 11 years ago
"IT" what each throttle injector? the TBI assembly? where are we failing? the amount of pressure needed for this TBI system...are we looking at fuel pressures here...this does not work off of pressure (tho needs some) but off an electronic pulse~
migration_judge_roy answered 11 years ago
Volts really don't smell like anything....the first time you put your electric heater on the first time this season...perhaps?
www.youtube.com/watch?v=lJEGigONelc --- should only have .5 - 1 volts at idle and no more than 4.5 - 5 at full throttle. Check this video out.
migration_judge_roy answered 11 years ago
Now that I've investigated this car...I kinda want one...there is a road near Langtry thats straight but bumpier than hell...riding in the MINI is shear torture...but this "luxury-liner" would be perfect~
migration_VoltaireT answered 11 years ago
Mkay, well i cross checked my 84 TC EECIV which runs well. She read exactly like you said, 1.2 at idle and evenly increased with the throttle. Checked my 81 (EEC III) in question again, and it read 3.6 at idle with even increases up to 7ish (or 3.5 volts up as it should). I cant seem to find any place to purchase a new sensor tho. The autozone site doesnt have it.
migration_VoltaireT answered 11 years ago
Nevermind i have found one online. $42. Im going to replace it then see what happens.
Hope you get her going soon. Good luck and drive safe.
migration_VoltaireT answered 11 years ago
Mkay, i did more research. n order to check the TPS on Ford EEC IV, the voltage should be as described, 1.0-4.5ish. However, on EEC III (like my car), the voltage is normally higher. 3-8ish. Thanks for the info anyway guys