3SGTE hard to start, runs fine

[nuk1ear]

really? thats all? I havent tried different crank timing, i thought generally for a 3sgte motor or most 4cyl you use 10deg? But ill give 5 and 0 a shot!

anyone else had to use small cranking timing?

[franksidebike]

really? thats all?

yes! please test this!
on my 2zyl. engine the crankig advance is 6deg.!
on my 4zyl. engine the cranking advance is 4deg.!
when idle both 14-16deg!
frank

[gruff511]

I am having this same issue today. Did you get any change by reducing the crank timing?

My timing is also set at 10*BTDC i will try reducing it when i get home. Hopefully that is all my problem is

[nuk1ear]

I havent had time to try and im trying to get an idle control valve first.

Did you get the same problem? Hard starting and backfiring? Have you only just installed the megasquirt, so the problem happened straight away from installing the megasquirt? Or was your car running fine and it just suddenly happened?

I havent tried the time yet, might try when i get home in a few hours! Let me know if you have any luck!

[gruff511]

IT worked!

lol i just finished installing msx3. i reduced my cranking timing from 10 to 6 and it started with out problem. i still took a good amount of cranks to fire up but i just need more fuel.

[nuk1ear]

nice, what engine? Also are you using an idle control valve? how open is it during cranking?

[gruff511]

nice, what engine? Also are you using an idle control valve? how open is it during cranking?

Im on the 420a and im using the stock iac stepper. i still dont really understand how the steps work on the iac motor because it could move anywhere between 140-180steps and my rpm wont move up or down. Right now its sits around 170. But i just noticed today that my idle would be around 1200rpm for a while with the iac at 170 steps then rpm would drop and idle steady at 900 while the iac motor never changed. UGH! i never get any consistent actions or re-actions from this iac motor.
I switched from "closed loop always on" to "stepper always on" and got better results so im currently on that.

[nuk1ear]

have you managed to tune the cranking timing yet? get any different settings? I picked up my idle valve (bosche of a hyundia) today and plan to wire it up in the next few days

[gruff511]

have you managed to tune the cranking timing yet? get any different settings? I picked up my idle valve (bosche of a hyundia) today and plan to wire it up in the next few days

No it still at factory settings.

[benckj]

I'm subscribing to this thread because I will be doing the same install on my MR2 3sgte soon. All this still has me a bit confused and a little worried so I'm busy doing my homework.

Jim

[nuk1ear]

ill be honest with you man. I built the whole harness myself, wires, connectors, all protection etc etc myself. I also built the ecu myself. Everything worked basically from the get go (electrically). The starting issue im having is mostly due to the lack of idle valve i think.\

But in a whole, its not really any easier to use a common brand ecu to do the conversion to stand alone. At the end of the day the same sensors etc need to be wired up, and the settings need to be adjusted correctly.

[benckj]

Thanks for those words of encouragement. I am an Instrument Engineer so I feel quite capable of completing the task just need to understand what I am doing.

I can buy the ECU built with a base program on it and then wire up myself. Once running reliably I'll take to a dyno shop and fine tune from there. Just don't want to have a whole host of problems to solve on gear I'm not familiar with and no help other than this forum. Especially don't want to get it wrong and blow my gen5 engine up!

If your interested this is a Newbie intro thread I started which has some pics of my car including engine bay.

viewtopic.php?f=94&t=43386

[nuk1ear]

haha fancy that, im a wire harness engineer for toyota lols

most errors are created by ourselves from what ive read so far. Generally, as long as you can understand toyota wire diagrams and system layouts you will be fine. MR2s are very simple because the Relay box basically only carries circuits for the engine and ECU alone, and basically nothing else. Only 2 w-w connectors which you can do what you like with pretty much (only a couple of circuits that run through it that you must keep). Its great i think, gives you lots of flexibility and the ability to use most of the stock relays and fuses too

[benckj]

That's all good to know.

I'd better let you get on with your thread as I've skewed it off topic far enough. Will be in touch.

[nuk1ear]

well it started up with the ICV easier. But now i need to figure out how to tune that stupid valve.

found that 90hz or 111hz works well, and give it about 20-30% is fully closed and about 70-80% gives fully open. So i tried closed loop, but it just shot up to 1900rpm and sat there lol. so then tried just Warm up only, but it doesnt work right. I gotta play around with the settings more. Hopefully it wont flood too much, maybe i should clean the plugs because last time i took them out theyre were very very black, but all the black cleaned off easily

[nuk1ear]

i cant for the life of me get this car to start reliably! I have no idea why. Sometimes it will fire right up without any worries, then others it will just crank and crank and never fire!

When it does catch, it stalls very quickly, after about 2 seconds. No idea why, It just wont hold.

[franksidebike]

in your log "2012-02-19_16.21.56" i can see you have Sync Lost Reason 11!
look her http://www.msextra.com/doc/ms3/syncloss.html
frank

[nuk1ear]

i dont ever get RPM dropping to 0 unless i purposely do it myself. I really dont think i have sync problems, if you look at the log i have a total of like 7 errors, each one happens when i stop cranking or something similar, they are never during cranking and never show any real indication of that being the problem (this is to my untrained eye).

That said, i havent tried cranking angle set to 0deg btc, thats gonna be my next attempt i think. I feel sorry for my starter motor

[franksidebike]

I feel sorry for my starter motor

make this:
remove spark plugs, no power to fuel pump, no power to the coils!
make a log from cranking and show to your Lost Sync Reason!
frank

[nuk1ear]

i can just unplug the coils and unplug the injector driver and do that too. If i do a single cranking set i wont get any loss of sync. Ill give it a shot tho and see if i get any.