Newbie style questions [1990 Rev1 N/A]

[d1iquid]

First off, great forum, I have already saved myself a couple of red faced moments from actually READING the information available

I have been enjoying my first foray into MR2 ownership with my 1990 Rev1 N/A Import, totally different beast to my previous daily a stage 1 mapped saab 9000, Couldn't corner for toffee but annoyed the hell out of the Focus RS drivers and Megane RS250 drivers I might be down on power now but the grin factor is leagues in front with the MR2..

Now the MR is not exactly running right...

It's currently running really rough when cold and refuses to idle below 1500 rpm even once its warmed up, hesitant and goes to cut out with normal driving, missing like mad, if you *drive it like you stole it* from the moment you turn the key it skips over the hesitancy and missing in about 400m and runs smooth as silk (albeit idling at 1500).

I will be changing all the usual suspects, dizzy, rotor, coil, plugs, leads etc and with an ECU reset hopefully this will settle down (as well as replace the exhaust system from downpipe up to the backbox as this has been cut/decatted and welded in half a dozen locations).

I've already changed the plugs, it habit, always the first thing I do so there are some decent NKG's in there but the ones that came out were NGK BKR6EGP ones, nowhere that I have looked state these are for anything other than the 3SGTE engine? would these have been causing any issue I guess would be the first question? I did pull the ECU fuses before I changed them over but I'm not convinced, might just diss the battery at the weekend.

The additional problem I am having that prompts this post is that when cold if I reverse out of a parking space and turn the steering the engine cuts out, it does the same if I drive down the road a short way and turn around, each time I'd be on full lock, once it dies and does not like to re-start, any idea's good people?

I'm out most of the evening but will look back in later on tonight.

TIA.

Simon.

[HighwayStar]

Hey Simon and congratulations on the purchase.
The issue sounds related to the cold idle system to my untrained ears. If the replacement of the electrical bits doesn't sort it I'd run it into a an affiliate to sort... there area few not too far away from you. Cold start temp sensor maybe?
That said I'm sure others will be along with some DIY advice to try out first. Keep with it and good luck. Great cars.

R.

PS If you do find you need new bits like sensors etc try TCB parts. Trevor there knows 2s well and has genuine and blueprint parts for all revs.

[dantheman]

Tricky one.

First have a go at reading the ECU codes to see if that gives you a clue. You bridge the TE1 and E1 ports in the diagnostics box at the right rear of the engine bay, then turn the key to on and count the flashing engine management light. 3 flashes [short pause] 5 flashes [long pause] would be 35.

To me it sounds like it could be 2 things. 1st the idle air control valve could be stuck open or not functioning correctly, causing the high idle. Because the engine is getting more air than the AFM has measured its running quite lean.

Alternatively it could be that the ECU is getting an incorrect reading for engine speed and hence running the engine all wrong (ie it thinks 1500 rpm = 750 rpm). As such when you turn the steering at slow speed, activating the steering pump at full load, the associated increase in load to the engine applied by the altenator is enough to kill it.

Not sure how likely the 2nd option is though. Also not sure on the specifics, i think engine RPM is measured from the dizzy. Perhaps its just your timing is really off.

[riot68]

No help on the issues I'm afraid but plus one for TCB, sure it will be simple enough to sort, pretty bulletproof...

[abovetherim]

For the high idle problems i would change your coolant temp sensor, they are only a few quid. Obviously you are going down the correct route of making sure the ignition components are upto scatch.
As mentioned above, if the new ect and making sure the coolant is topped up and bled doesn't sort it out then also a new t stat (i always use oem) and whip the idle control valve out and give it a clean with throttle body cleaner (you can also clean the TB butterfly at the same time).

Furhter to this if your t stat is stuck open then the coolant will take a long time to warm up and your engine will also hence the ecu idling high.

To sum up;
Make sure your ignition components are tip top
Make sure your cooling system components are tip top
Clean icv and throttle body

[d1iquid]

Thanks for the replies, plenty of food for thought and with parts selling like mad on the dead saab I should have enough surplus cash over the next few weeks to replace the whole shebang.

TCB Sounds like a good place to go when I order everything I need

One more quick question, Anyone running KV85 leads on their N/A? I had them on my Vtec Accord and they were a vast improvement over the originals, just wondering if people were using them and noticed any difference over the blueprint/originals?

S.

[d1iquid]

Right,

Following up on this now that some parts have been swapped out - others not so, now I actually know what engine I have......

Following the Essex meet last Thursday I've found out some very useful information from a very helpful and friendly group of people, roll on the next meet

I'm Rev1 Chassis, Rev 3 Engine so half the ordered parts don't fit (if anyone wants, brand new dizzy, 7mm leads and a thermostat for a Rev1 N/A import let me know)

So, I've swapped out the knackered pipercross filter for a green twin cone (proper Orville green as well ) replaced the air speed sensor in the intake, plugs and rotor for now.

We ran the diagnostics at the meet - no faults at all. It was noted that the aircon sensor was not connected but all the related idle pipework was, I cut and extended the cabling to get the sensor connected however the end connector is rounded and the aircon one mouted on the rear wall is rectangular, not to be daunted i cut the connector and found that a couple of those small speaker spades slot right on so *in theory* the aircon sensor is now connected.

Could someone with a rev3 and aircon pop a pic in here with their sensor/ wiring setup at all so I can double check what I have done? soon as my post count is up I'll be able to post images for something more helpful myself, I've run the car since connecting it up and nothing went pop but its not made any change either, just wondering if I have connected up a totally unrelated plug for the aircon....

As mentioned after changing those few items nothing has changed, It still idles too high at 1500 (about 1600 now that there is actually an adjuster screw in the TB to stop it sticking) and it still goes to cut out and die on you unless you bury the throttle every time you pull away when cold, 1/2 mile down the road it will run and pull away regardless of throttle position without a hitch but still idles at the 1600 mark when stopped, until its past this point it just bogs down like it is missing like crazy, I get out accelerated by KA's until it gets over its *cold* problem.

I've played with the TPS and no amount of adjustment has the slightest effect to idle speed... ??? confuzzled but I guess a new one of those as well to add to the orders.

I have still to check the coil pack and swap out the other items once replaced (leads, dizzy and thermostat). This is more an update of where I am more than anything (bar the pic of a rev3 aircon sensor plug in situ).

I'll get everything else checked and changed before I give up and go bother the likes of Westfield

[HighwayStar]

Is it when cold or when it's been wet or damp?

[d1iquid]

Does not make any difference, cold, wet, damp, hot, bone dry, all the same.

light tweak of the throttle and it will cut out, rev the bolts of it and it will cough, splutter, bog itself down a bit then spring to life, do that a few times and it will run faultless for the rest of the day as long as you keep it running, stop for an hour or so and you need to go through the same process.

Its manageable for now but I go from a very tight road with just enough room to get the car through onto a main road and when you go to pull out and it bogs down on you, kinda gets the heart racing.. I tend to wait for a quiet moment and avoid rush hour as much as possible

[toxo]

If you sign up to be a premium member you can advertise those parts in our For Sale section (or, if you bought genuine, you can take them back to Toyota for restocking).

Just to clarify, the little pointy sensor in the air intake isn't air speed, it's air temperature - a rev3 engine will be MAP based.

It sounds like you are suffering from a half-assed engine swap. The fact that you have mismatched sensors (aircon) and loom suggests it may not have been done right! Nothing we can't overcome but get your post count up so we can see some photos!!

[d1iquid]

Well I'm *almost* there toxo, had a feeling it could well be the case of an incomplete swap, I never buy anything that just works......

I'll be premium soon enough

Simon.

[Rob66]

Hi Simon,

If the problem persists its worth trying Luke at Pacific Works (took me 40mins to get there from Romford). I had a similar cold start idle problem and Luke changed all the usual suspects on Saturday and its running great again now.

Good luck with it. Rob

[AlexD]

Hi Simon,

If the problem persists its worth trying Luke at Pacific Works (took me 40mins to get there from Romford). I had a similar cold start idle problem and Luke changed all the usual suspects on Saturday and its running great again now.

Good luck with it. Rob

+1 on this (my cars in there now) he's a legend

[stuMR2lee]

Hi Simon,

Good Essex Meet last night.

If you are not in too much of a hurry I'll try and dig out my spare TPS & ISCV sensors for you to try as discussed and bring them along to the next meet. I've also got a spare plug with wires so you can set them up with a multimeter. I've got the instructions somewhere. Would be worth taking off and cleaning up the Throttle Body as well just to rule that out.

Stu (celica!)