4.6 to 5.4 swap notes clarification
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4.6 to 5.4 swap notes clarification
The swap notes on this site https://www.f150online.com/forums/ar...wap-notes.html are awsome. Really going to help me make the swap from 46. to 5.4 in my 1998 F150 4x4. I am hoping I can get some clarification in the ignition area though. The notes mention that all 5.4 are cops but pre 2000 4.6l are coil packs. I am reading between the lines in the swap notes but is it safe to assume that if I stick with a '99 5.4 I could use my existing 4.6L coil packs and simply run plug wires on the 5.4??
Last edited by dmstanl; Dec 4, 2012 at 04:08 PM.
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From: MI
The swap notes on this site https://www.f150online.com/forums/ar...wap-notes.html are awsome. Really going to help me make the swap from 46. to 5.4 in my 1998 F150 4x4. I am hoping I can get some clarification in the ignition area though. The notes mention that all 5.4 are cops but pre 2000 4.6l are coil packs. I am reading between the lines in the swap notes but is it safe to assume that if I stick with a '99 5.4 I could use my existing 4.6L coil packs and simply run plug wires on the 5.4??
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From: Joplin MO
Yes. You will need to use the harness and ECU that's in your truck, properly modified.
Ignition: All 5.4 engines use Cop ignition. . 2000 and later 4.6 use COP ignition. 1997-99 4.6 engines use coil packs. It is easier to wire your 5.4 using the harness from the 4.6 and use the 4.6 ignition coil packs if applicable. If you use the 4.6 Coil pack ignition you will have to fab a bracket for the driver side coil pack.
Engine harness: To use a 4.6 PCM to run a 5.4 engine: The IAC harness must be relocated to the rear of the throttle body elbow. The oil sender wire on the 4.6 may be too short so measure or test fit the harness to see if it must be extended. All 97-00 and some 2001 4.6 engines use some sort of intake manifold runner control valve. Remove it from the 4.6 and plug it into the 4.6 harness and bolt it to the engine some where out of the way. Note; you can get a tune to remove its function and eliminate it all together.
All 97-98 4.6 engines use an Engine Coolant Temp sensor (ECT) and an Engine Coolant Temp sender. By the 99 Model year the ECT was dropped in both the 4.6 and 5.4 harness as the Cylinder Head Temperature sensor (CHT) was used for the PCM to monitor coolant temps. None of the 00+ 5.4s use ECT sensor or sender. Some of the 99 5.4s still use the sender to feed info to the instrument cluster. You will have to tap the intake manifold crossover pipe to fit the sensor(s) if your 4.6 has them and the 5.4 doesn’t.
Engine harness: To use a 4.6 PCM to run a 5.4 engine: The IAC harness must be relocated to the rear of the throttle body elbow. The oil sender wire on the 4.6 may be too short so measure or test fit the harness to see if it must be extended. All 97-00 and some 2001 4.6 engines use some sort of intake manifold runner control valve. Remove it from the 4.6 and plug it into the 4.6 harness and bolt it to the engine some where out of the way. Note; you can get a tune to remove its function and eliminate it all together.
All 97-98 4.6 engines use an Engine Coolant Temp sensor (ECT) and an Engine Coolant Temp sender. By the 99 Model year the ECT was dropped in both the 4.6 and 5.4 harness as the Cylinder Head Temperature sensor (CHT) was used for the PCM to monitor coolant temps. None of the 00+ 5.4s use ECT sensor or sender. Some of the 99 5.4s still use the sender to feed info to the instrument cluster. You will have to tap the intake manifold crossover pipe to fit the sensor(s) if your 4.6 has them and the 5.4 doesn’t.
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From: La Salle,MI
I have a 97 expedition with the 4.6L and getting ready to swap in a 5.4L for a 01 f150.
I looked through all the notes and understand most of them. I have a question about the knock sensor though. Do I reuse the 4.6 one in the 5.4 block or do I have to rewire the 5.4 sensor for the 4.6 harness?
I looked through all the notes and understand most of them. I have a question about the knock sensor though. Do I reuse the 4.6 one in the 5.4 block or do I have to rewire the 5.4 sensor for the 4.6 harness?
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Thats a good question. My plan was to go with the 4.6L and worry about it if it didnlt work. Probably would be better to know up front though.
GLC's response about tapping the intake for the ECT brought back memories. I had an 81 trans AM that I dropped a 67 283 under the 81 intake manifold. The difference in years left me with no place for the Coolant Temp sensor. I ended up tapping a freeze plug and it worked fine.
GLC's response about tapping the intake for the ECT brought back memories. I had an 81 trans AM that I dropped a 67 283 under the 81 intake manifold. The difference in years left me with no place for the Coolant Temp sensor. I ended up tapping a freeze plug and it worked fine.
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From: Las Vegas, Nv.
When I did the swap in my 98 F150 I spliced the wire from the 5.4 knock sensor to my 4.6 harness. Mainly because I didn't want to remove the intake to access the sensor. Seems to work, no codes.
Mike
Mike