Ford Mustang Ecoboost Forum banner
1 - 7 of 7 Posts

· Registered
Joined
·
40 Posts
Discussion Starter · #1 ·
Hey everyone,

I need some help with my 2017 ford eco boost mustang, i have roughly 142,000 miles on the car but the current engine has roughly 70,000 miles on it.

Well, the problem I’m currently having is that the engine light came on, the first code was P1450 with the tank vacuum. The dealership replaced the purge valve for free because I had already paid for the previous purge Valve back up in August.

However, the car is misfiring when the car starts up and they said it was cylinder three. The technicians checked for fluid in the engine and they did test the pressure as well and they were perfect and free of coolant or damage.

The dealership is recommending i replace all the spark plugs and the part that goes ontop. The total cost is $550 for parts and labor.

My question is, do you guys think this will solve the issue because they are unable to find any other cause. I just don’t want to waste $550 on this repair if it won’t fix the issue.

Thank you for the advise!!
 

· Registered
Joined
·
24 Posts
How many miles on the current plugs? I going to assume 70,000 miles. Plugs are rated for 100K. However as a personal opinion they should be changed out after 50K max especially since we have a boosted engine whether stock or tuned. If the plugs have 70K on them it might worth it to change the plugs only. Are they replacing all coil packs. If the misfire is only on cylinder 3 then only one then they should change is number 3.
After saying this you maybe aware it is common that misfires at start up on cylinder 3 is usually caused by a bad head gasket. Even though they did a pressure test did they leave it long enough (over night preferable) and check if any coolant was in any of the cylinders. However my bet would be on the bad head gasket.
 

· Registered
Joined
·
132 Posts
Hey everyone,

I need some help with my 2017 ford eco boost mustang, i have roughly 142,000 miles on the car but the current engine has roughly 70,000 miles on it.

Well, the problem I’m currently having is that the engine light came on, the first code was P1450 with the tank vacuum. The dealership replaced the purge valve for free because I had already paid for the previous purge Valve back up in August.

However, the car is misfiring when the car starts up and they said it was cylinder three. The technicians checked for fluid in the engine and they did test the pressure as well and they were perfect and free of coolant or damage.

The dealership is recommending i replace all the spark plugs and the part that goes ontop. The total cost is $550 for parts and labor.

My question is, do you guys think this will solve the issue because they are unable to find any other cause. I just don’t want to waste $550 on this repair if it won’t fix the issue.

Thank you for the advise!!
That ain't gonna fix it. Swap out the coil pack from another and see if it still misses
 

· Registered
2016 Mustang Ecoboost, 6-speed manual, premium
Joined
·
96 Posts
Plugs and coil packs can be bought and done on your own or by a trusted friend easy enough. And for much less that $500
 
  • Like
Reactions: Coyote Chaser

· Registered
Joined
·
2 Posts
I am having the same issue. I’ve had misfires like 4 times in last 6 months. And the dealerships can’t figure why. They changed the cylinder head, spark plug and still the issue keeps coming back. Now latest they tell me that the pcm is causing it and later that it’s not the pcm but all cylinders are misfiring. Really not sure what is happening. Any help is appreciated. Thanks.
 

· Registered
Joined
·
132 Posts
I am having the same issue. I’ve had misfires like 4 times in last 6 months. And the dealerships can’t figure why. They changed the cylinder head, spark plug and still the issue keeps coming back. Now latest they tell me that the pcm is causing it and later that it’s not the pcm but all cylinders are misfiring. Really not sure what is happening. Any help is appreciated. Thanks.
Like I said the whole thing needed to be replaced. I guess not all mechanics know that. With a new head it has to be in the block. They won't know until they tear it down. I'm not sure what the percentage of them have head problems but it's enough to cause an issue. There are thousands of them on the road that never have any problems.
 

· Registered
Joined
·
99 Posts
I am having the same issue. I’ve had misfires like 4 times in last 6 months. And the dealerships can’t figure why. They changed the cylinder head, spark plug and still the issue keeps coming back. Now latest they tell me that the pcm is causing it and later that it’s not the pcm but all cylinders are misfiring. Really not sure what is happening. Any help is appreciated. Thanks.
Try a new ignition coil, pretty simple install for even someone new to cars.
 
1 - 7 of 7 Posts
Top