'93 Concorde 3.5L intermittent starting problem

[jschneider84]

Okay. It's a strange bird here. '93 Concorde, 3.5L, started experiencing cutoff of engine while driving several months ago. Diagnosed via codes on dashboard and replaced O2 sensors, camshaft position sensor and fuel pump relay (not needed on the relay, just to be sure). Now having "intermittent" starting problems where engine cranks, no start condition. Other times, engine will do 2 turns of the starter and fire right up. Replaced crankshaft position sensor and engine started right up. Shut engine off and 5 minutes later, engine would not start. Symptom is erratic, does not correspond to either hot or cold condition and all relays appear to be normal. Engine runs perfectly when actually running. NO CODES SAVE FOR THE 5-5 SHOW ON DIAGNOSIS. Has been doing this for 2 months now, seems to be getting worse. Any help out there?

[mooselips]

I having the exact same problem... it just dies when driving... then starts up no problem a few min later.

[sendwade]

From what I understand the camshaft position sensor and crankshaft position sensor have much to do with this symptom. I am working on one right now. I will let you know more. If computer does not complete ground to automatic shutdown relay this type of problem occurs. This from what I understand can be a intermitten problem. Any takers on this one? There was a posting for checking out the out put from the sensors as they tell the computer to complete the ground. I am not sure where the posting is at now. I remember it is quite a lengthly procedure involving a VOM and turning over the engine by hand to get the numbers. I am looking for a work around right now.

[clutch492]

Did anyone figure this one out? I see the post is somewhat old. Can you fill me in on the conclusion? I am working on one right now myself.

[ChuckvB]

My problem is almost the same, It sometimes does not start in the morning, (no spark) but later in the day it seems to most of the time. Once it starts it seems to keep on starting until the next morning. No codes but changed the crankshaft sensor, camshaft sensor, and swapped the ASD relay. Shaking harness produces no changes when running or or not starting so I do not think I have a back harness issue. Maybe a ground or something with a thermal mechanical aspect to it. Any ideas?