Will any Vh45 fit in a 90 q45?

[REC]

I'm looking at purchasing a used motor and building it for my car. Most of the available engines are from years 94-96. Will these fit or do I need a 90-92 vh45

[Q45tech]

In 1994 there was a change to CAS and harness that make it necessary to create a single plug [from CAS] to 2 plug [wiring harness] adapter when trying to interface larter engine [94-95] to 90-93 harnesses.

Forget the 1996 engine as too many differences with OBDII changes to even work in a 1995 much less a 93.

Finding the connectors and CAS dangle and creating the interface requires you cannabalize the CAS from old 90-93 engine then find a connector from 94-95 engine harness.

[SuperHatch]

In 1994 there was a change to CAS and harness that make it necessary to create a single plug [from CAS] to 2 plug [wiring harness] adapter when trying to interface larter engine [94-95] to 90-93 harnesses.

Forget the 1996 engine as too many differences with OBDII changes to even work in a 1995 much less a 93.

Finding the connectors and CAS dangle and creating the interface requires you cannabalize the CAS from old 90-93 engine then find a connector from 94-95 engine harness.

This is 90% correct, except that a 94 CAS is two plug just like the 90-93 CAS. However, only the Secondary circuit shares the same plug, the primary circuit is redesigned and is the same on all 94-96 plugs.

If you get a 90-93 motor, any type will work and drop right in. If your car has TCS and the donor motor doesn't, swap TB setups, the same applies if it's the other way around as well.

If you get a 94 motor, it will drop right in, use your 90-93 coil harnesses, ignitor chips, etc. The secondary circuit on the CAS will plug right in, the primary circuit will require you to cut/spice the newer connector onyou your old harness or make a jumper harness.

If you get a 95 motor, the above applies but there is no secondary circuit to plug in on the CAS at all, you won't get a CEL.

Avoid a 96 motor, you can make it work but it is significantly more work.

[elwesso]

essentially its the same (and better with the guides and injectors) just have to splice in the CAS wiring... If you're going to tackle an engine swap, doing the wiring shouldnt be a big issue

If you can get the connector from the donor car for the CAS that will make for a clean install.

[REC]

Thank you gentlemen...much appreciated.

[rushps]

After complaining that I have no difficult and expensive import cars to work on since I wisely got out of the Conquest / Starion game, my good friend (?) Dave (dsagers) turned me on to the Q45. although parts are not as expensive as the Star/Quest ($300 for used injectors) they are every bit as hard to get accurate information.

I am in fact doing the conversion wiring for someone right now, someone who did not check with his friend before he did the engine swap(91 engine into 94 Q45), this person sent me an e-mail with a link to this and suggested I give my 2 cents, lets call this person Dave.

O.K. under the hood there are subtle differences between 93 and 94 as mentioned they are relatively easy to work around providing you use some components from the 90-93 as described above. The difference is from the firewall back, they are very different cars as far as the wiring goes. The key is to run the components that mate up with the harness your vehicle has as long as you are going backwards, however if you try to go with a 90-93 in a 94 vehicle, I would say you need your head examined, right Dave?

Having said that there are some nice advantages to running a 94 harness in a 90-93, such as ECU controlled fan, better EGR, Injectors, and diagnostics, but this would require engine, harness, & ECU as well as some wiring changes to the trans control module and the addition of some relays for the fans, oh and fans. Most of the wires for this are found in the brown plug near the ECU.

Well that’s my 2 cents, good luck.

[Panther in a Q45a]

The car dsagers bought from Qsiguy had the under dash wires "modified" when the laughing gas was added when the second PO listed it on ebay for a hefty price. The buyer then actually blew up the engine with a laughing gas explosion in the intake manifold.

Might be a six hour job if you need two hours to read the manual. The TCU is a non-issue, must use the TCU designed for the transmission, ECUs do not care which TCU is plugged in.

What experience do you have that you ended up with this job?
Modified by Panther in a Q45a at 6:46 PM 5/20/2009