Checking fuel injector
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Joined: Oct 2019
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Checking fuel injector
I have a misfire on #2 cylinder on a 4.2L V6 in 2001 F-150 extended cab with 4 speed, overdrive automatic transmission. I have two questions.
1. I cannot find a NOID light for this rt Fuel Injection, only for throttle body injection. Anybody know where I can get one?
2. Does the intake manifold have to be removed to replace the injectors? (I found only two videos on this and they removed the manifold. But they also said the first checked manifold for gasket leaks)
I want the noid light to make sure injector is getting signal before I take things apart. I am going to check and make sure the plug is getting spark and is not fouled or has a cracked insulator first. Always check the easiest and cheapest first. I replaced the ignition block and wires at the same time about 5 years ago.
1. I cannot find a NOID light for this rt Fuel Injection, only for throttle body injection. Anybody know where I can get one?
2. Does the intake manifold have to be removed to replace the injectors? (I found only two videos on this and they removed the manifold. But they also said the first checked manifold for gasket leaks)
I want the noid light to make sure injector is getting signal before I take things apart. I am going to check and make sure the plug is getting spark and is not fouled or has a cracked insulator first. Always check the easiest and cheapest first. I replaced the ignition block and wires at the same time about 5 years ago.
Senior Member
Joined: Dec 2015
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From: Utah
First off, just an FYI - a cylinder misfire is one of three things.... lack of spark, fuel, or compression. A cylinder misfire is most commonly a spark plug, COP, or plug wire issue. I don't know if the 4.2 has COP's or wires though, so you will have to determine that.
Next, a NOID light is simply an incandescent light. IMO, the best one on the market is the universal light made by Lisle. It will work in MANY applications.
Here is a video I took using my NOID
Next, a NOID light is simply an incandescent light. IMO, the best one on the market is the universal light made by Lisle. It will work in MANY applications.
Here is a video I took using my NOID
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Joined: Oct 2019
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Checking with a stethoscope the injector seemed to be operating. Noid light showed it getting signal. Checked and was getting spark to the plugs. So did what I should have done in first place and pulled spark plug. The plug had fouled, replaced plugs and everything good.
These plugs are on a 60,000 mile replacement schedule so we tend to forget about them and this truck is driven only a few miles a week. Looked at old notes and those plugs were at 80,000 miles.
My first car was a '67 Camaro with 327 ci engine. This was not a problem with those cars because every year you replaced the plugs, points and condenser every spring.
These plugs are on a 60,000 mile replacement schedule so we tend to forget about them and this truck is driven only a few miles a week. Looked at old notes and those plugs were at 80,000 miles.
My first car was a '67 Camaro with 327 ci engine. This was not a problem with those cars because every year you replaced the plugs, points and condenser every spring.
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Joined: Nov 2017
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From: Washington
You had a plan and followed it. Many people get all *****-nilly. The plugs seem to wear faster than Ford expected. I think my schedule is 100,000 miles but I changed them at 80,000 and they were way past needing it.
For the record, these ignition systems are wasted spark. Three coils, six spark plugs.
For the record, these ignition systems are wasted spark. Three coils, six spark plugs.