Hi,
My 1999 Ford Expedition recently stopped blowing out any heat. Blower blows fine, but not enough heat. Brought it to a local shop and they replaced the thermostat. Picked up the truck and bearly any heat and truck runs rough. Check engine light came on half way home. Brought it right back to shop and they said that it takes the thermostat awhile to "open" up and that I probably need new spark plugs. Truck ran smoothly when I brought it in. Spark plugs were changed at approx. 90,000 miles. Could the shop have disrupted anything or caused the truck to misfire and engine light to come on. Computer check said something about cylinder #7 misfire, but something seems weird. Please advise. Your Expedition will heat up in 5-10 minutes. Open the radiator cap when the engine is cold and make sure the coolant is up to the top and that the coolant reservoir is at the full mark.
Your vehicle is 9 years old, the cooling system might need flushed out. When it's hot, feel both heater hoses. If only one is hot and the other warm, the heater core is clogged up.
#7 Misfire is the #7 cylinder misfired because a bad spark plug, bad/loose wire to that cylinder or bad coil at that cylinder.
They might of accidently pulled the wire lose or damaged the coil. You could swap that coil/boot with another cylinder, and see if the trouble code moves to there.
Which motor do you have? Mileage? Thanks for the reply. Truck has 5.4 engine and 130K miles. Ran fine before I brought it in. Shop claims they replaced the rad fluid. Said they had heat going after letting it run for 1/2 hour. They said they took the truck for a test run on the highway and that is when the misfire began. Could it be a vaccum leak somewhere that they could have knocked something off? Just seems odd that "all of a sudden" truck runs like this. A vacuum leak would suck more air in the intake and trigger a Catalytic Convertor/O2 sensor code.
It seems logical they did something, but coincidental things do happen. They worked on the front of the engine and the problem is on the side.
40,000 miles is enough to think you have a bad spark plug or coil on cylinder #7.
Quote:Firing order is 1-3-7-2-6-5-4-8 Passenger side of engine starting at front and going back is 1-2-3-4 Driver's side starting at front going back is 5-6-7-8.
Pull #7 sparkplug and check it for wear. Also swap #7 coil with another cylinder. If it is bad, you will get another trouble code for the new cylinder. AutoZone pulls and clears trouble codes for free.
coil looks like this, attaches on top of sparkplug
Brought the truck back to the shop and now they are saying "yeah, it's the heater core. You're getting heat in the rear and it's gonna take us at least 6 hours to fix it". What the?? Why didn't they tell me that before. First it was the thermostat needs to open up, takes a couple of times. Now it's the heater core without even looking at it today.
I had a small amount of heat before the thermostat was replaced, only on the first and second setting. Still the same amount now. Blower still works fine. Air-cond. works great. No smells. No obvious leaking in the truck or on the ground. Hose to radiator is warm.
Engine light is still on. When I asked about changing to a different cyclinder and then checking the computer diagnostics, they said "oh, yeah, well, uh, yeah, I guess we could do that".
What's next? Told them I would call them later. Sounds like they are not the best on troubleshooting. Atleast it's on the right track now to get fixed. Wait till you get the price on replacing a heater core on that one. Your going to pass out. Car Repair Talk's forum.
My 1999 Ford Expedition recently stopped blowing out any heat. Blower blows fine, but not enough heat. Brought it to a local shop and they replaced the thermostat. Picked up the truck and bearly any heat and truck runs rough. Check engine light came on half way home. Brought it right back to shop and they said that it takes the thermostat awhile to "open" up and that I probably need new spark plugs. Truck ran smoothly when I brought it in. Spark plugs were changed at approx. 90,000 miles. Could the shop have disrupted anything or caused the truck to misfire and engine light to come on. Computer check said something about cylinder #7 misfire, but something seems weird. Please advise. Your Expedition will heat up in 5-10 minutes. Open the radiator cap when the engine is cold and make sure the coolant is up to the top and that the coolant reservoir is at the full mark.
Your vehicle is 9 years old, the cooling system might need flushed out. When it's hot, feel both heater hoses. If only one is hot and the other warm, the heater core is clogged up.
#7 Misfire is the #7 cylinder misfired because a bad spark plug, bad/loose wire to that cylinder or bad coil at that cylinder.
They might of accidently pulled the wire lose or damaged the coil. You could swap that coil/boot with another cylinder, and see if the trouble code moves to there.
Which motor do you have? Mileage? Thanks for the reply. Truck has 5.4 engine and 130K miles. Ran fine before I brought it in. Shop claims they replaced the rad fluid. Said they had heat going after letting it run for 1/2 hour. They said they took the truck for a test run on the highway and that is when the misfire began. Could it be a vaccum leak somewhere that they could have knocked something off? Just seems odd that "all of a sudden" truck runs like this. A vacuum leak would suck more air in the intake and trigger a Catalytic Convertor/O2 sensor code.
It seems logical they did something, but coincidental things do happen. They worked on the front of the engine and the problem is on the side.
40,000 miles is enough to think you have a bad spark plug or coil on cylinder #7.
Quote:Firing order is 1-3-7-2-6-5-4-8 Passenger side of engine starting at front and going back is 1-2-3-4 Driver's side starting at front going back is 5-6-7-8.
Pull #7 sparkplug and check it for wear. Also swap #7 coil with another cylinder. If it is bad, you will get another trouble code for the new cylinder. AutoZone pulls and clears trouble codes for free.
coil looks like this, attaches on top of sparkplug
Brought the truck back to the shop and now they are saying "yeah, it's the heater core. You're getting heat in the rear and it's gonna take us at least 6 hours to fix it". What the?? Why didn't they tell me that before. First it was the thermostat needs to open up, takes a couple of times. Now it's the heater core without even looking at it today.
I had a small amount of heat before the thermostat was replaced, only on the first and second setting. Still the same amount now. Blower still works fine. Air-cond. works great. No smells. No obvious leaking in the truck or on the ground. Hose to radiator is warm.
Engine light is still on. When I asked about changing to a different cyclinder and then checking the computer diagnostics, they said "oh, yeah, well, uh, yeah, I guess we could do that".
What's next? Told them I would call them later. Sounds like they are not the best on troubleshooting. Atleast it's on the right track now to get fixed. Wait till you get the price on replacing a heater core on that one. Your going to pass out. Car Repair Talk's forum.
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