Replacing a non mivec engine into a mivec car

[vzr1800]

Hi has anyone attempted this?

I bought a 94 mivec with a dead engine and replaced it with an engine out of a 96 GR that was going perfectly.
I used the mivec intake manifold because it doesnt have the air flow meter on it.
when I start it its running at about 4000rpm!

anyone know what I can do to make it run properly short of using the GR wiring loom and ECU?

[Daniel2019]

Could be stepper, TPS or idle screw, or most likely one will be a vacuum leak somewhere.

Double check all of your rubber vacuum hoses were fitted to the manifold properly and go from there.

And, I did the opposite. I put a Mivec engine into my GR.

[vzr1800]

I checked all those, I used the stepper motor off the GR so not that. I tried adjusting the idle screw and also the TPS to no avail!

Checked all the vacuum hoses and no leaks!

If I pull the electrical plug on the small device on the bulkhead that has a small vacuum hose on it, then it comes down to a reasonable idle but is rich as with black smoke coming out the exhaust!

I considered using the GR intake manifold but didnt think that would work seeing it normally uses an air flow meter and the mivec doesn't have a cable for that to plug into!

[Daniel2019]

Have you got a MAF sensor installed?

[vzr1800]

Sorry what is a MAF sensor and where do I find that on the car?

[Daniel2019]

MAF sensor is the sensor that goes between your air box/filter and your intake manifold. Is only found on non-mivec engines. Mivec engines have a MAP sensor. Does the car have any engine light on?

[vzr1800]

Ok , I guess that is the mass air flow sensor!

It didn't have any lights on when I first had it running but it did yesterday after I was playing around unplugging stuff to see what difference it made!
I have disconnected the battery to reset it but havent tried to see if there are any lights on again yet!

I have got the MAF sensor from the Gr but there isn't any connection on this cars wiring loom to hook it up to!

[Daniel2019]

Ah of course different loom.

In that case I am not sure. I don't know if the MAP sensor from the mivec loom would work on the non mivec engine. This'd be a question for Bennoz or someone smarter than me to answer

[vzr1800]

Just been and connected the battery up and started it, the engine check light is not on now and it is still running at close to 4000rpm

[vzr1800]

Yes that was my thought as well, change the loom and use the GR intake manifold and ECU and MAF, looked like it might be a big job changing out the looms, I have the complete GR as well for parts.

[Daniel2019]

Nah loom is easy to swap, just change ECU and feed loom through grommet on firewall. Would be a bit annoying to do with the engine there though, if not impossible.

Check error codes and it will give you a starting point. Will be something MAF/MAP related I think.

[vzr1800]

It looks like the heater would have to come out to get the loom out through the firewall!

Had another play around with it this morning and noticed a high pitched whistle coming from the intake area, took it off and cleaned and sealed it, it appears that the brackets at the back near the firewall were keeping the manifold up a bit as well.

the whistle has gone now and it is idling at only 2000rpm now!

i found by disconnecting the vacuum control valve on the firewall it will idle at 800rpm but is very rich with black smoke comming out the exhaust!

still at a loss to what I can do now!

[Daniel2019]

Heater doesn't have to come out but aircon piping in the engine bay gets in the way.

Check your error codes its a vacuum leak or MAF/MAP problem.

[vzr1800]

Just checked for error codes and there are none!

[Daniel2019]

Did you check using this guide http://ftoaustralia.com/v3/viewtopic.php?f=21&t=14667

[vzr1800]

Yes I did, I even unplugged the vacuum control valve so see if it came up with that code and it did.
I swapped the PCV from the mivec engine and that slowed it down a couple of hundred revs, but it is still around 2000rpm.

unplugging the vacuum control valve slows it down to about 800rpm but it is running way to rich!

I also tried to remove the loom out of the GR and even standing in the engine bay I couldn't get it to come out more than a couple of inches even though it is all disconnected on the other side.

[Daniel2019]

OK in that case if you are 101% sure there's no vac leaks then I would look into swapping your stepper motor out and checking your idle screw. Idle screw should be all the way in (turn it clockwise so its tight. Don't turn it crazy tight, just so it's snug and won't vibrate loose)

[vzr1800]

Yes swapped the stepper motor off my version R in my profile photo and that didnt make any difference, and yes screwed the idle screw right in.

I know what you are saying about the vacuum leak because when I took the manifold off and sealed it down this morning it slowed it from 4000rpm to 2000.
I have been over every vacuum hose several times I there doesnt appear to be any leaks!

[bumpak]

This must be the first engine swap where someone has decided to go backwards. ill go to auslancer and people will be putting 4G15's in their evo's.

[vzr1800]

Yep I'm starting to think that .I bought it cheap with a stuffed motor and thought I would just use the motor out of the damaged GR that was sitting in the shed so I could have a cheap drive around car!