A 2004 3.4 engine into a 2002? What are the differences? [Archive] - GrandAmGT.com Forum


View Full Version : A 2004 3.4 engine into a 2002? What are the differences?

sugar ray
04-19-2010, 12:53 AM
Just curious as to the differences in the 02 and 04 production years regarding the 3.4 engine? My 2002 Grand Am is in superb condition. My local wreckers got a 2004 that was recently written off in a rear end collision. I just happened to be at the wreckers when they were towing it in. While I do NOT need the engine, the price they are offering it to me for is almost too good to pass up. Wouldn't be a bad idea to just store it in the garage for a rainy day! It only has 47,000 kms (NOT miles)
NOT even broken in yet!

However, when the wrecker punched up the info on his computer he seemed to think it wouldn't be compatible. Listing the Am's were compatible years 1999 through 2003. At first look under the hood the 3400 looks identical in every way comparing it to mine. However I realize things can be different.

My buddy once transferred what he THOUGHT was a matching 2.3 engine from 1991 Tempo into a 1992 Tempo. After install, the engine ran but NOT well. Upon further research we discovered that in 1992 Ford had changed the blocks slightly and equipped them with a cam sensor. With NO cam sensor built in to the 91 block, the car just went into LIMP mode and wouldn't run properly. The ONLY fix was to transfer the 91 computer into the 92.

Would love to avoid a scenario like that. Again, I don't NEED the motor, but the price is right with that low mileage. What problems would one run into transferring a 04 3400 into a 02?

young gun
04-19-2010, 11:34 AM
i don't know but i'm pretty sure 99-05 are easily interchangable. how much are you getting it for? you could buy it and i would take it off your hands seeing as i need a engine.

04-19-2010, 02:03 PM
Well more like 2000-2005 should be interchangeable, 99 motors can work but only if you switch upper manifolds and injectors. Everything else should be the same or similar enough to use, especially going from a 2002 to a 2004.

04-19-2010, 02:14 PM
maybe he means the 3.4 out of the camaro?

04-19-2010, 02:35 PM
doubt it, camaros havent came with a 3.4 since 95. 96 they switched to a 3800. Not to mention Camaros stopped being produced in 2002

04-19-2010, 02:51 PM
I'm sorry lol i need to stop multitasking didnt see 2004 for some reason lol:asshat

04-19-2010, 04:32 PM
The difference between 2002 and 2004 is almost nothing. They added an improved water pump in 2003. They also made some kind of improvement to the starter solenoid and switched to iridium spark plugs. They made a slight improvement to the crankshaft thrust bearing, and also changed the size of the bolt hole for the rockers in the cylinder heads from 10mm to 8mm. None of this stuff would affect the ability to interchange the engine with an older one. The only thing that might is they changed the front camshaft journal where the camshaft position sensor reads, and changed the sensor lead on the engine harness. That sensor lead comes off the main injector harness though, so as long as you get all that with the engine, you should be good to go. I know they changed the position of the signal wires on the cam sensor plug between years, but they should be going to the same pins on the main injector harness plug (by the alternator), so you should be able to just plug it in and go. :thumbs:

sugar ray
04-19-2010, 10:20 PM
GREAT information AaronGT

You are a big help to these boards and have loads of AM knowledge. Thanks again :applause: