1986 LTD II

I have acquired this car, not new, but its in fairly good shape to be as old as it is. It's a 3.8 TBI and I have this problem where it won't start when its hot. I'll explain, the car will fire right up when it is cold, then from the time it cranks you can drive it just about anywhere. I usually make 30 mile trips to work. Now if I cut it off and let it sit ~5 minutes, it won't crank when I try to crank it. It just spins and spins and doesn't crank. I have injector pulse and spark, or so it seems. I've replaced the TFI Module seeing it was the same symptoms I had seen before. Well after the car won't crank, if I let it sit a few hours it will crank right up and go on its merry way, till I cut it off again. Any advice where to start looking to trouble shoot this? Thanks.

Reply to
Tully
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Tully opined in news:4wxid.37230$ snipped-for-privacy@bignews1.bellsouth.net:

I dont know crap about CFI except that the injectors are prone to leak.

And that should be easy to find out.

And do you try flooring it to start when starting hot? The computer sees that and shortens the injector pulse.

Reply to
Backyard Mechanic

dig deeper into the electrical and you will find the problem.

had the same problem on my LTD II. got the recall notice and took it to the dealer. before then had the same problem you are having. fire up great when cold and would start right up if you didn't let it sit for over 10 minutes. after 10 minutes, you would have to wait hours so the engine would cool down.

well, the dealer said the replaced what the recall was for. i picked the car up and all that day, it started and ran fine. next morning, dead as a door nail. would spin, no start. like no spark. called dealer. they sent tow truck. when i went to pick up the car, they said there was no charge. when i asked why, they said there is TWO pieces that make up this circuit and they replaced the one and not the other. it was the other piece that they didn't replace that went bad. no problem after that for as long as i owned the car.

hope this information helps.

~ curtis

knowledge is power - growing old is mandatory - growing wise is optional "Many more men die with prostate cancer than of it. Growing old is invariably fatal. Prostate cancer is only sometimes so."

Reply to
c palmer

Thanks for the information, I was thinking it could be an injector that was leaking, I'll have to look into it.

Reply to
Tully

Thanks for responding, now I'll go see if I can find a list of recalls on this particular model see if I can get it working. Thanks again.

Reply to
Tully

For what it's worth, a couple pieces of advice from someone who has babied an '85 LTD for the last 15 years:

1) You are saying 'or so it seems' about the presence of spark when the engine refuses to start. Make sure to confirm that. Pull one of the wires, attach a spare plug and put it on something metallic. Look for a spark while an assistant works the ignition (or turn the switch to 'ON' and use a remote starter). Works better in a dark garage. If no spark, I would look inside the distributor. The plastic material which encapsulates the Hall effect type pickup tends to disintegrate over time. Replacing the TFI might have made it worse, because that's what the TFI plugs into. Check that the sensor is intact and that the connection to the TFI is solid. The distributor needs to come apart to replace the sensor, and it's not an easy thing to do. You may be better off with a rebuilt distributor if you find that the sensor has fallen apart. 2) Make sure that the fuel pump is working. You should hear it for a couple seconds when you turn the ignition on. 3) Confirm that you have injector pulse. There is a $5 tester for this purpose. 4) If no injector pulse or you can't hear the pump, check that the ECM (engine computer) has power. It's powered through a relay that likes to fail. 5) When the problem occurs, perform a KOEO diagnostic test. All you need is a test light and a paper clip. Minor problems won't prevent it from starting, but something major will. There may be a lose contact somewhere, which disengages when things get hot and affects a lot. In my case, the +5V reference would disappear, rendering every single sensor useless. If you can't interpret the codes, post them here and someone will try to help you. 6) If you haven't found anything else, I would advise checking fuel pressure. You can buy or rent the gauge. There is a test port on the fuel line. Read the instructions and be careful not to spill any gasoline around a hot engine! The TBI regulator is not vacuum compensated, so no rubber diaphragm to break, but who knows.. You may have a bad pump, a clogged filter, a grossly leaking injector - all leading to loss of pressure. 7) There is a simple instrument which will pulse the injectors and let you check if they work properly by watching the fuel pressure.

Let us know what you found

Reply to
Happy Traveler

I definitely have spark, this is the first thing I checked a few months ago before I stopped driving the car. Upon your recommendation I opened the distributor back up today and looked inside with a flashlight, coating the bottom looks like there is this "black stuff" (maybe insulation, or oil). Couldn't tell if the hall effect switch was deteriorated or not just the black substance in the base of the distributor.

: 2) Make sure that the fuel pump is working. You should hear it for a couple : seconds when you turn the ignition on.

This I have checked, and it is pumping properly. There is what seems like an intermittent problem here, I'll get to that in a minute.

: 3) Confirm that you have injector pulse. There is a $5 tester for this : purpose.

Injectors are pulsing, checked visually and with a noid light.

: 4) If no injector pulse or you can't hear the pump, check that the ECM : (engine computer) has power. It's powered through a relay that likes to : fail.

This is where the intermittent problem comes in. I am diagnosing this car myself and it is sometimes difficult to be in two places at once. But I have noticed it seems like sometimes the ECM relay isn't functioning. Its in the right kick panel and when it works you can hear it click and the fuel pump engage. This doesn't happen all the time, I could be imagining it, but when I go to check it out it works properly.

: 5) When the problem occurs, perform a KOEO diagnostic test. All you need is : a test light and a paper clip. Minor problems won't prevent it from : starting, but something major will. There may be a lose contact somewhere, : which disengages when things get hot and affects a lot. In my case, the

+5V : reference would disappear, rendering every single sensor useless. If you : can't interpret the codes, post them here and someone will try to help you.

No codes set as of right now. I might try to go drive it and check it again.

: 6) If you haven't found anything else, I would advise checking fuel : pressure. You can buy or rent the gauge. There is a test port on the fuel : line. Read the instructions and be careful not to spill any gasoline around : a hot engine! The TBI regulator is not vacuum compensated, so no rubber : diaphragm to break, but who knows.. You may have a bad pump, a clogged : filter, a grossly leaking injector - all leading to loss of pressure.

Fuel pressure is adequate, and the injectors do not seem to be leaking pressure. The pressure stays up even after letting the car sit for a while.

: 7) There is a simple instrument which will pulse the injectors and let you : check if they work properly by watching the fuel pressure. : : Let us know what you found : : Right now I am leaning torwards the hall effect switch or the ecm relay. I may be barking up the entirely wrong tree, wouldnt' be the first time with this car. This is where I am at at the time being, the car is becoming a headache. Thanks for your input.

Reply to
tully

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