2005 xc90 new motor, CEM questions.

Acain79 · Post by **Acain79** » 28 Jun 2018, 19:04

Hey guys, so my 05 xc90 got a burnt valve awhile back, long story short guy who was fixing it went to prison for a year after it was torn apart, sat open for too long and rusted motor out. Had a shop swap the motor, now no fuel or spark, cranks for a sec then stops. Replaced fuel pump, no luck, replaced fuel pump module, no luck, heard if the battery in key fob is dead that would trigger anti theft and not start, replaced battery no luck, so now I'm looking into the fuel pump relay in the CEM. My question is with the new motor, will my CEM work with it or do I need a different one? Could it just be the relay? Any input is appreciated. I've dumped too much into this thing.

Post by **RickHaleParker** » 28 Jun 2018, 19:28

You should spend another $80.00 on a DiCE interface, Install Vida2014D_RePack so it can tell you where it hurts.

Post by **SuperHerman** » 28 Jun 2018, 20:49

First RickHaleParker's suggestion has merit. At least see if the shop can provide you some codes. VIDA will help here. Also look up the built in system check and see what error codes are reported. I don't recall the process, do a search, but it will tell you what modules are communicating and which ones are not - it is a "free" place to start.

To answer your question - new motor will work with prior CEM. The motor is "dumb" and is interchangeable, but it needs the same motor mounted electronics (sensors, injectors, ...) as the original so that it communicates correctly to all the car's computers.

Can you describe in greater detail what you mean by "cranks for a sec then stops". Does the car actually run for a second (which would mean you are getting fuel).

The dead battery in the FOB should not matter - it is the transponder chip that is relevant.

You could have bad fuel, no fuel, no spark or electrical issues.

Try and describe everything with greater detail and see if the shop has any codes. Maybe it is a crank position sensor - codes would really help.

A motor swap, is not complicated, but reconnecting everything correctly causes some problems.

Post by **ggleavitt** » 29 Jun 2018, 16:21

The folks above are right on the money, and VIDA and DICE will pretty much be a mandatory if you can't see an obvious physical issue.

One thing I might add to the mix is an electrical diagram-http://www.volvowiringdiagrams.com/volv ... iagram.pdf in the event you wanted to do some cable tracing. 2006 link is noted as the 2005 version does not open this site, pretty sure wiring is identical between the 2 years.

Replacement engine came from another XC90?

Post by **RickHaleParker** » 29 Jun 2018, 17:12

2006 link is noted as the 2005 version does not open this site

Just point him to XC70/XC90 directory and then he can get the correct file.

Acain79 · Post by **Acain79** » 05 Jul 2018, 20:45

Ok thanks guys, I'll get the codes from it soon, when I turn the key the starter turns for 3-4 seconds then just stops, seems like it's not getting fuel, or spark. Would sitting for so long with no power to it cause problems with anything? Tank was empty for pretty much the whole time I'm guessing, we put new gas in it, replaced the fuel pump, replaced the fuel pump control thing in the back right wheel well, old one was pretty corroded. Not sure where to go from here. I'll have to get that vida, and see what it sees I guess. I do remember my wife saying the mechanic did see like 27 codes or something. Oh and the last time I was there I remember seeing a service airbag light was on. Not sure why, it wasn't ever deployed. Thanks again.

Post by **ggleavitt** » 05 Jul 2018, 21:11

If you're in a pinch, might be able to find a regular old OBDII reader and plug it in, that'll give you something. Almost nothing folks can do without a point of reference, other than to encourage re-tracing all the connections. Could be more than one thing not working properly.

And this is an '05 what engine? 2.5T, T6, or V8?

Acain79 · Post by **Acain79** » 05 Jul 2018, 21:23

2.5T. I have a bluetooth code reader I can plug into it, just need to go to the shop to do it.

Post by **RickHaleParker** » 06 Jul 2018, 05:20

Would sitting for so long with no power to it cause problems with anything?

Yes, the battery can self-discharge and sulfate. This can produce the symptoms your having.

Acain79 · Post by **Acain79** » 06 Jul 2018, 06:58

The battery was disconnected the whole time, old battery was shot so i put a new one in.