98 4.6 engine swap
 

I have a 98 expedition with a 4.6. I have a friend with a 2001 f150 4.6. What is involved with putting in the 2001 engine. I would use my plug wires and coil packs. Looking at the intake there is some coolant hose connections that are different and the there are some different sensor locations. Does anyone have any info. Thanks.

You will have to use the 2001 intake and exhaust manifolds. The 2001 engine has PI heads, the 1998 does not. Manifolds are not interchangeable.

I noticed some of the intake sensors are arranged different between the two intakes. The ones behind the alternator for instance. That's probably the first thing I noticed. The expedition has a remote oil filter also so. The coolant hoses could easily be rerouted but sensors I'm not sure. I would hope the Mass Air could compensate for air and fuel. Just looking for someone with some experience with this. I'm trying to see if it's worth the hassle. 4.6 rebuilds aren't cheap and it's hard to find a decent used pre PI engine.

I have read that you can add the extra front intake manifold temp sensor by drilling and tapping. That was my first concern, the nonpi had two sensors upfront, the pi one.

I appreciate your response. While looking through the post search I see you have done atleast a topend swap to pi heads and intake. My son's 4.6 last week decided to break something in the bottom end and now has a dead cylinder, about 30 #, and is pressurizing the crankcase. The PCV is sucking oil like crazy. A coworker has a 2002, not 2001 like I posted, 4.6 in a F150. The engine is in great condition and I was interested in an engine swap. My 98 is in an expedition. The obvious things we noticed was a coolant hose in the front passenger side instead of the back and a single sensor behind the alternator, where my 98 has the two temp sensors. If you could tell some other possible difference it would be much appreciated. I know I could most likely just use the coil packs and wires from the 98 and possibly drill and tap the intake for the second temp sensors. I'm just hoping the 98 ecu would operate the 2002 fine as long as the appropriate sensors are connected to it. Thank you for help. Barry

Well I swapped the engine. It fired up fine and idles fine. The issue I had now is excessive engine ping, like predetonation. Higher octane helps but it still has some chatter. The two computers may have different timing tables. One issue I had with the swap was I had to change the wiring pigtail on the knock sensor. I don't know if the sensor is causing an issue and the 98 computer can't retard the timing. I also used the the front cover and accessories from the 98 engine as well as the stamped 2002 reluctor wheel for the ignition trigger. The 98 had the thick cast wheel. The wheels had identical spacing in the trigger points on the wheel and both fit snug with no slop on the crank key. There is no check engine lights as of yet. The last engine which was a rebuilt 4.6 I got two years ago always had a little detonation with bad fuel but nothinlike this. That engine had no knock sensor, so I drilled and tapped the block and added the original sensor. Anyone have any ideas or suggestion to curb the chatter. Maybe colder spark plug?

A used engine may have excessive combustion chamber deposits. Try running Techron through a few tanks of gas - and/or consider getting a Motorvac or BG intake cleaning job done.

If you have to, you may need to get a programmer and some custom tunes to get it to behave. Check the OBD2 for any pending codes, the knock sensor may not actually be working.

Thanks. I'm getting ready to clean the MAF, It has to be oily from the oil that was dripping from the air intake tract. It hasn't triggered a light yet but hasn't been driven a great deal. I'll keep at it.

Quick reply. When we first drove it, my son was driving, it sounded like bolts shaking in a coffee can. Worst ping ever. It had about a quarter tank of 87 octane. I came home and put about 4 or 5 ounces of Lucas octane booster in it. It got a little better. We drove around and put 6.5 gallons of 93 in it. It got better still but had a lot ping, still enough to make me worry a lot. My son took it for a spin for a spin to a friends house. When he got back he said it was continuing to get better. I posted here and went to clean the MAF. I took it for my first drive, absolutely no ping. I don't know if the carbon got blown out, the fuel soaked in, or the MAF helped, or everything. I will definitely still keep an eye on it the next few days. Do these computers have adaptive learning and adjusted itself? I have never heard anything ping like that, even my 65 mustang with a 200 shot when the auxiliary fuel pump quit and melted the head gaskets. I was really worried the 98 and 2002 union was a bust but right now I feel a whole lot better. There is at least hope. Thanks for the help. Keeping my fingers crossed.