prefacelift/facelift engine differences?, High idle

pistol pete · March 13, 2020, 14:30

Hi All

Done an engine swap on our preface lift MR, it spun a bearing
So i put the engine in that came from the sprint car, this is a face lift.

it runs really well and drives brilliant.

It has a high idle (1600-1800rpm)
I do have an engine light up that i will code read later after work

Before i go hunting for vac leaks etc.. and normal diagnosis.
Are there any differences between the two engines sensor wise? As using the original wiring loom and ECU but all the sensors from the face lift. just making sure no differences in the throttle bodies or anything simples

I would have done more investigation. but literally finished it all and quick test run and used it to get to work. just thought worth a quick ask

thanks
Pete

househead · March 13, 2020, 14:33

Is that cold or warm idle?

Mine (FL) will cold idle at about 1500 (so not loads less than numbers quotes) but once warmed up will drop to about 750.

In any case, there would be difference between warm and cold and if these are warm numbers then that's way out.

Carolyn · March 13, 2020, 14:59

No differences.

pistol pete · March 13, 2020, 16:05

thanks..
Nope thats warm..

ill do a code read see what it says then hunt for vac leaks etc

Nvy · March 13, 2020, 16:49

IACV valve, I had lots of problems with mine and solved it by spraying a whole can of carb cleaner on it. It was dirty as hell.

Gaz mr-s · March 13, 2020, 17:01

Quote from: Nvy on March 13, 2020, 16:49IACV valve, I had lots of problems with mine and solved it by spraying a whole can of carb cleaner on it. It was dirty as hell.

I was considering mentioning that too, but since the engine was working ok, unless it's been disturbed it's unlikely to be that.
But if there is air in the coolant it might, but in my recent experience working on two cars the idle wasn't high, or just high, it was erratic. I've had to burp my radiator several times, & that's since I realised what the problem was.

And I only took my IACV off as recommended to clean it. The small shaft in it runs on a shielded bearing. I think it should have been a sealed type.

pistol pete · March 13, 2020, 19:05

cheers peoples
I will have a looks!!!
the engines been sat in my garage since September so could easily be that

shnazzle · March 13, 2020, 19:12

Quote from: pistol pete on March 13, 2020, 19:05cheers peoples
I will have a looks!!!
the engines been sat in my garage since September so could easily be that

I'd put money on it

pistol pete · March 13, 2020, 20:14

would it bring up the EML light too?

Gaz mr-s · March 13, 2020, 20:33

In the faffing I did with the two cars it never brought up a code that suggested the cooling system (air blocks) were the problem, but there is a coolant system code, one at least.
I'd bleed your system....maybe granny/eggs here.... engine hot, turn heater on full & bleed at the radiator.

Supposedly it's better elevating the car at one end...I can't remember which though...googling will tell you. If it is the problem, the coolant level will change with each heat cycle.

I changed the radiator of my first 2 & didn't have the faff bleeding it that working on the IACV created.

Ardent · March 13, 2020, 20:41

if raising. raise the rear.

pistol pete · March 14, 2020, 06:21

Cheers people's.. yeah I'm gonna check the idle control and have another system bleed..
I shall report back asap

Call the midlife! · March 14, 2020, 09:20

Couple of things from someone who's had previous IACV issues.
In my case the symptoms were rhythmic racing and hunting once warmed up but at no point did it bring up any EML.
Apologies if you already know all this but removing the IACV involves removing two small coolant pipes so don't do it with the engine at temperature and have a couple of bolts ready to plug the ends (can't remember but think they're m6s).
Before you remove the valve make some witness marks to make sure you get it all back in the same place as the position also controls idle speed.
Be gentle if the valve spindle doesn't move freely, the magnet in the solenoid is quite fragile.
There's a dedicated seal in the face of the valve, easy to get hold of but be prepared for it to need replacing.
Or just have a read of the "how to" before starting 😆

pistol pete · March 16, 2020, 06:11

Thanks peoples!!
I have not had a chance to go back and look at it yet (dropped off our classic mini to a friend after we sold it and picked up a £100 Mk2 MR2 to add to the collection)

Ill let you know when i have had a good chance to burp the system and play around with it

Thanks !

pistol pete · March 29, 2020, 09:24

It's all sorted was still a small air lock as suspected in throttle housing..
Disconnected hoses and pumps large coolant line to bleed the air out

Thanks