I have an '85 tbird with a 3.8L and 151k miles. After starting and letting it warm up for a few minutes, when I take off down the road, the engine starts running rough and dies. After three or four restart sputtering and dies, the problem clears up and the engine runs fine for the duration of the use of the car. It did do it once before I got out of the driveway and sometimes it does not do it all. The only engine code coming back is for the O2 sensor always reading lean during the engine on test. The O2 sensor is switching on and off on a sensor tester.
Is it some temparture sensor miss reading? :confused: Did start to happen when the weather cooled off.
Thanks for any suggestions.
Ford Thunderbird 1985 3.8L. :screwy:
I would start by replacing the 02 sensor, they are relatively inexpensive and easy to change. They are also know to go bad and give false readings.
this sound like the problem I have with my cougar, on mornings when its cold and I stop or going less than 15 miles the car just dies without doing anything go to neutral, starts again, it does this everytime the car is cold, when I get to the highway it runs ok, could it be the same problem as thunderbird232 the only think is theres no engine code , took it to the mechanic and he doesnt know yet whats wrong, he told me maybe the computer is bad, right now im running the cougar with the map sensor disconnected and is the only way it doesnt die when its cold
Thanks, but kinda easier said than done in this case. The sensor seems to have become one with the exhaust manifold, it won't budge. Not to mention very little room to get a tool in there for leverage. It's the original, which may not be a good thing either. :shakehead
Give it time. Spray PB Blaster on it every evening for a few nights. It'll come out.
i wanted to add it helps if the engine is warm also;)
Ive had a cold start problem with my 88 5.0 start die start die once it runs for a few it is a-ok till it cools off again.
Just unplug the o2 sensor and try it a couple of days, if it still dies that ain't your problem..
I've had two TFI modules do just as your are describing.
Easy to replace?
Seems like I remember something of a recall, lawsuit or something dealing with the TFI's being pr0ne to problems.
i think im having the same problem right now.
cold morning, the car stars ok... take off down the road, fine.
come to a stop or slow creep and the car starts to shake like mad. really rough and shaking a lot. and if not careful, stalls.
but its starts back up with no problems, and then into the day its fine when the weather warms up a bit. i need to know what to check cuz i dont want to have to fight this everyday this winter.
wheres the o2 sensor? and what sideeffects would disconnecting it to troubleshoot have???
thanks
02 sensors are located in the exhaust pipe (cant remeber if itn the manifold or not) youll see them, get a haynes gius and can telly ou how to check them, but if they havent been replaced i would do it regardless prolly about time.
well it could be a hand full of things. a bad map sensor a bad 02 senseor bad tfi or the starting of a clogged fuel filter. or possibly the fuel pump getting weak on ya.
Mine is located on the exhaust manifold, driver's side near the fire wall.
Disconnecting the O2 sensor for the short term won't hurt anything but may cause the EEC computer stay in close loop mode which may mask the problem, if it is cause by another sensor. The motor will run rich and over time harm the catalyic converter, or so I was told.
Can the TFI module be changed without yanking out the Distributer on a 3.8L?
yes it can. there are 2 or 4 bolts that hold it into place. if you have the tfi removal tool this job is alot easier.
You mean the EEC will stay in OPEN loop... The missing o2 sensor will be made up by backup programming in the EEC, which is likely more accurate than info from a 150k mi sensor. Yes it will go a little rich, but not enough to harm the converter. It's likely been dead for the last 40 or 50K mi anyway.