Corrosion in coolant, low idle, twitchy steering

[kasa]

Hello,

I've recently bought a 130k REV3 NA on the cheap side which seems to drive well, has some issues but nothing that I felt was too bad at the time. I only recently got into cars so any help would be greatly appreciated.

I bought it while I was in London, I then found some deposits in the coolant which I later learned was corroded crap. I had to drive it back to Manchester but first took it to a local mechanic who flushed the system out twice and topped it up with red coolant. I then drove it back the whole way with no issue.

I'm a little worried about what could be badly corroded. I was planning to have the cambelt+tensioner done so will do the water pump as well. Should I get the head gasket checked? There's no mayo under the oil cap. Anything else I could check? Not sure if its related but the temperature gauge shows the car warming up a lot slower than other MR2s I've seen, but otherwise sits half way when warm. Could the thermostat just need changing?

It has a low idle when cold, maxes 1200rpm and might fluctuate a little. I've read the IACV may need a clean and I was planning to try this myself.

I also noticed on the long drive, above 70mph the steering feels really light and twitchy, but is otherwise nice and stiff at slower speeds. Is this a power steering or suspension/alignment issue? The car is lowered and the ride is rough as hell...

[peteV6R5]

wow thats a lot on 1st post.

first of all welcome to the OC.
check out know your 2 above, loads of hints tips and guides.

coolant, youve had it flushed and changed, bet it aint been done for years which resulted in the dirty coolant you can see.
if you have the waterpump changed (good idea) when doing cam belt, you will need more replacement coolant so maybe worth doing another flush then as well for peace of mind.
warm up time, varies depending on how cold the weather is. if it sits at half way when warm and does not vary then all is good. but if changing cam belt and water pump for the extra £10 ish its worth putting in a new stat as well.

your idle sounds pretty normal for these things. mine use to do the same. high 1200 idle on initial start up reducing to c 1000 after few seconds then reducing to c800 when getting warm. yes the ICV can need cleaning. but does it need it now?? your call.

front end lift / going light at speed especially in high wind / cross wind situations are pretty common.
REV5s have a set of front speed flaps that damp down this issue.
main thing you need to do is get it 4 wheel aligned. and get some decent tyres on (depending whats on already)

lowered but you dont say how, springs or coilovers. then which springs.
some set ups are very hars on the road (thinking out loud eibach / tien / hsd as examples), some are more complient (apex / bcs as examples).

hope that helps

[kasa]

Thanks Pete! I'll do the whole lot.

I thought the idle should be around 2000rpm initially? Thats what I usually saw when I was first looking to buy. So it doesn't matter too much as long as its stable?

They're springs but can't tell which. I was thinking of raising the car to its original height just to avoid scraping the front and for a more comfortable ride.

[abovetherim]

Hi speed feel can be affected by not having the under trays fitted. Worth checking they are still there.
Also is your car UK or import? Reason I ask is if it's an import, a speed converter may have been added and this now tells the steering to turn off at a higher speed.
Alignment and ride height can also be a big factor here as can the condition of the dampers.

Unfortunately these cars are of an age where things like dampers and bushes are old and tired and the cost of the car doesn't warrant the expense in some people's minds. If refresh you were to refresh your suspension the costs can quickly add up.
Have a look at tcbparts to give you an idea of prices of stuff.

However if you go ahead and refresh the driving experience is night and day.