before i begin heres a little background info on my problem. so i have an 05 coupe(automatic) and i crashed it a few years ago and its been sitting in my backyard this whole time, a few weeks ago i found an 06 6spd coupe for super cheap and the body was in great condition so i bought it because i figure i can just swap engines and everything would be great. Im not sure whats wrong with the 6spd but it doesnt start. The guy i bought it from thinks its an electrical problem. Should i try and diagnose whats wrong with it or should i just say **** it and swap engines?

 

Only you can make that decision. It'd be almost impossible for us to diagnose what's wrong on the internet. You need a competent mechanic to go over that car from front to back, especially you know nothing about it's history. The swap would be very involved and require a bunch of work converting the manual car to an automatic. Here's an idea of what you'd be looking at: https://g35driver.com/forums/drivetr...-6mt-swap.html

 

Swapping engines is not that simple since the 5AT and 6MT of those years use different engines. The short block is the same though.

I would definitely troubleshoot the fail to start issue since that's about 1/100th the work compared to a motor swap.

Does the engine CRANK?

 

you have it backwards.. . I want to put the engine into the 6 speed. The car with AT only had like 37k on the engine when I crashed it.. The body damage is beyond repairable and the engine on the 6 speed has 133k.

 

yea but it doesn't start. It sounds like it wants to start but it is having a hard time and can't do it. I'd prefer to swap engine cuz the AT has 37k only but the 6spd has 133k (swapping into the 6spd which is the one that won't start)

 

Swapping a non-revup motor into the 6MT might work but it will definitely be throwing a service engine light because it will be looking for the 2 extra cam sensors that won't be there as well as the 2 extra cam actuators (exhaust variable timing was added to the rev-up motor) and those components don't even exist on the 5AT models.

If the engine cranks strong then it might just be a bad crank sensor (CKP) or cam sensor (CMP), fortunately you have extras laying around since you have a second motor to work with, I'd start by using a paint pen to mark which sensors are which and just swap them all around to see if it fires up.

If the engine is cranking weakly then that needs to be resolved first, maybe the battery, maybe the starter.

If you're competant at assembling the top end of a motor then you could always take the short block from the low mile engine and use it with the rev-up block, just be sure to keep the oil pump from the rev-up because it's designed for the higher redline on the 6MT.

 

awesome (: im mechanically inclined but i have no training or experience. i have a couple of friends who work in shops and are more than competent though so im not even really worried about the cost of swapping. I just dont want to be wasting time, money and energy trying to diagnose a mystery problem if it wouldnt be that much harder for someone to help me with the swap. I mean since its possible to do i know im going to want to make the swap eventually just because of the difference in millage. The AT engine only has 37k, where as the 6spd has 133k.

 

if i take the short block and use it with the rev up block would i still get the CEL lights like you had mentioned?

also, the battery is brand new, i just bought it, and ive already checked the starter ( i removed it and used a battery to test it and it functions perfectly) so it shouldnt be either of those.

 

No if you kept the same heads with all the extra stuff for the exhaust timing then the car wouldn't know the difference. Something to consider if you are thinking of eventually going that route is to do a light rebuild of that other block, sure it only has 30k miles on it but the factory piston rings were junk to begin with so if you're going to have it torn down to a short block I would re-ring it just to save future headache with oil consumption problems.

 

I wouldn't bother putting much thought into swapping engines between these 2 cars. They are completely different motors and will require swapping the ECU and everything else which could possibily lead to other compatibility issues as well since the '06 is a slightly newer and might have controls for features that your '05 car in didn't its ECU. Plus there's the issue of the manual to auto swap and which will require some modification to at least a few things and removal of some other things (clutch master, etc).

You could just try to sell your old motor and trans if you get the '06 running and just drive the '06. I bet that '06 probably burns oil like crazy though, so keep that in mind before you go investing heavily in that. It's a fairly common problem on the 6-speed rev-up motors as they get up in the mileage.

If you do decide to jump into this, hopefully it will be you doing all the work yourself rather than paying someone else.

For the curiosity factor, you have any pics of your crashed up '05?

 

yea i have some pics somewhere, if i cant find em ill just take some during the day tomorrow. so since it sounds like the consensus is to troubleshoot the engine rather than the swap , anyone think they might be able to point me in the right direction? it sounds like it wants to start but it wont turn over all the way, if i leave the battery connected it will drain it, the trunk button doesnt work, the lights that show when i try to turn it on are : RAS, REV, the check engine light, a light that looks to me like it is an airbag. All the normal lights on the instrument cluster turn on but none of the gauges move at all. I had taken the starter off because someone i had come look at it said it might be the starter but after i had removed it i used the battery to test it and it functioned properly (the gear thing popped out and spun) so i guess it wasnt that either