I need a Lincoln LS V6 expert. My car is a 2003 Lincoln LS with 3.0L V6 engine and automatic transmission, manufactured January 2003, 150K miles (VIN 1LNHM86S93Y659890). This is the 2nd-generation car with throttle-by-wire and PCV valve on driver's side valve cover. I love it but I'm beginning to love to hate it.
Sorry for the long post but I'm trying to include enough detail to give a good picture of the problem.
I bought this used car a few months ago and have enjoyed it. "Auto-Check" indicated good history and previous owner indicated he had purchased the car used in 2006 and had maintained it well. Until a few weeks ago, it ran great. A few weeks ago, it went into "limp-home" mode without prior warning or other symptoms. When the tow-truck arrived to haul it to my home, I was surprised to find it started normally and could be driven onto the truck bed. I had it towed anyway out of concern it might fail again (instrument panel showed both the "wrench" symbol and the check-engine light). After I got it home, I drove it and found that it would run 5-6 minutes, then cut off as though there was no ignition; 2-3 minutes later, it would start again and run 5-6 more minutes.
I drove it to Autozone and asked them to read codes in the diagnostic system. They found the following.
P0446
P0606
P1235
P2107
P2110
Because I've researched this forum enough to know these cars are sensitive to coils and plugs, I replaced all 6 of both (Motorcraft OEM plugs, gapped correctly, and Hungarian-made Visteon coils). Thanks to the articles I found here, I was able to do the work myself. All the old plugs were OEM Motorcraft and looked like they were burning correctly. Of the six old coils, only four were OEM Motorcraft so I assume at least two had been replaced previously. No oil in spark plug wells or other evidence of leaks at valve-cover gaskets, intake manifold air valves, or PCV sysytem. I pulled the upper intake manifold but not the lower manifold. I re-used the six upper intake manifold gaskets after careful cleaning and inspection (no gasket sealant, just re-installed them "naked") and torqued everything properly.
When I put everything back together and tried to start the car to bleed the cooling system, I found the battery almost dead as though something had been draining it. I have no idea what might have caused that ... hadn't noticed anything before and hadn't experienced any prior problems. It's a new Interstate Megatron, purchased by previous owner. Although the battery barely had enough power to crank the car, it did eventually start. Since then, the car seems to have similar problem as before only now it won't run 5-6 mintues ... runs only 60-90 seconds, then dies (but can be re-started immediately). It won't run long enough to allow the cooling system to be bled.
I've seen forum posts suggesting the problem could be leaking intake gaskets, throttle body, or faulty engine management computer. To rule out the easiest of the 3, I replaced the upper intake gaskets I'd re-used initially with new ones from local Lincoln dealer. While I had the intake manifold removed, I also checked the ignition transformers to make sure they're grounded properly to the rear side the motor. Also checked to make sure there's continuity of throttle body wires from throttle body to PCM.
I need advice regarding how to further test throttle body and computer, also any other ideas you might have about what the problem might be. Check-engine light and wrench light is still on. Since I haven't been able to drive back to Autozone to get codes read again, I finally bought a scanner. The battery was completely disconnected for hours yesterday while I was working on the car so I assume any stored codes were erased. After I put the intake manifold back on last night, I re-connected the battery and started the car. As usual, it ran for apprx 90 seconds and died (check-engine light and wrench light on, no response to accelerator pedal). I connected the scanner and found apprx 20 codes (!) ... most of them related to transmission and throttle body. I can't imagine what's causing transmission codes ... the car hasn't been shifted out of Park for since I parked it in the driveway after my initial visit to Autozone to have the codes read days ago.
Thanks in advance for your help. I'm running out of patience with this car.
Sorry for the long post but I'm trying to include enough detail to give a good picture of the problem.
I bought this used car a few months ago and have enjoyed it. "Auto-Check" indicated good history and previous owner indicated he had purchased the car used in 2006 and had maintained it well. Until a few weeks ago, it ran great. A few weeks ago, it went into "limp-home" mode without prior warning or other symptoms. When the tow-truck arrived to haul it to my home, I was surprised to find it started normally and could be driven onto the truck bed. I had it towed anyway out of concern it might fail again (instrument panel showed both the "wrench" symbol and the check-engine light). After I got it home, I drove it and found that it would run 5-6 minutes, then cut off as though there was no ignition; 2-3 minutes later, it would start again and run 5-6 more minutes.
I drove it to Autozone and asked them to read codes in the diagnostic system. They found the following.
P0446
P0606
P1235
P2107
P2110
Because I've researched this forum enough to know these cars are sensitive to coils and plugs, I replaced all 6 of both (Motorcraft OEM plugs, gapped correctly, and Hungarian-made Visteon coils). Thanks to the articles I found here, I was able to do the work myself. All the old plugs were OEM Motorcraft and looked like they were burning correctly. Of the six old coils, only four were OEM Motorcraft so I assume at least two had been replaced previously. No oil in spark plug wells or other evidence of leaks at valve-cover gaskets, intake manifold air valves, or PCV sysytem. I pulled the upper intake manifold but not the lower manifold. I re-used the six upper intake manifold gaskets after careful cleaning and inspection (no gasket sealant, just re-installed them "naked") and torqued everything properly.
When I put everything back together and tried to start the car to bleed the cooling system, I found the battery almost dead as though something had been draining it. I have no idea what might have caused that ... hadn't noticed anything before and hadn't experienced any prior problems. It's a new Interstate Megatron, purchased by previous owner. Although the battery barely had enough power to crank the car, it did eventually start. Since then, the car seems to have similar problem as before only now it won't run 5-6 mintues ... runs only 60-90 seconds, then dies (but can be re-started immediately). It won't run long enough to allow the cooling system to be bled.
I've seen forum posts suggesting the problem could be leaking intake gaskets, throttle body, or faulty engine management computer. To rule out the easiest of the 3, I replaced the upper intake gaskets I'd re-used initially with new ones from local Lincoln dealer. While I had the intake manifold removed, I also checked the ignition transformers to make sure they're grounded properly to the rear side the motor. Also checked to make sure there's continuity of throttle body wires from throttle body to PCM.
I need advice regarding how to further test throttle body and computer, also any other ideas you might have about what the problem might be. Check-engine light and wrench light is still on. Since I haven't been able to drive back to Autozone to get codes read again, I finally bought a scanner. The battery was completely disconnected for hours yesterday while I was working on the car so I assume any stored codes were erased. After I put the intake manifold back on last night, I re-connected the battery and started the car. As usual, it ran for apprx 90 seconds and died (check-engine light and wrench light on, no response to accelerator pedal). I connected the scanner and found apprx 20 codes (!) ... most of them related to transmission and throttle body. I can't imagine what's causing transmission codes ... the car hasn't been shifted out of Park for since I parked it in the driveway after my initial visit to Autozone to have the codes read days ago.
Thanks in advance for your help. I'm running out of patience with this car.