Old 1.2 MA12 - problems getting it up and running

E

egres_svk

Hi guys..

i've got an old, 5 years sitting still micra in a garage, it has MA12 engine with electronic igniton and ECU unit under passengers seat (3 connectors, size approx 15x20cm)

thought i would fire it up and get out of the garage.. then give it to one of my friends, (i used it for spares because it does not have slovak registration book so it is not road legal)

I bought few litres of fresh petrol (did not want to start with 5 yrs old one), checked for a spark (strong..) and after 15-20 secs of cranking it fired up (carb was dry.. it needed to pump petrol inside)

at first attempt, it idled for 20 secs and died.. another 5 attempts did not get it running longer.. then i found the oil pressure sender, but unfortunately not mounted into the engine, but inside on the dashboard.. then i mounted it, replaced the 2 litres of oil which got out through the hole under pressure and cleaned the mess.. sigh..

that was yesterday.. today i tried to fire it up again.. it ran, but the idle was like periodic 400-700-400-700 rpm and with each period it was more obvious that it is going to stop.. after minute or so it died.. it is impossible to start the engine right after stopping.. everytime i had to wait at least 30 secs.. another attempt to fire it up lasted only few seconds.. it fired up, was stable for 3-4secs and died..

a bigger problem is, that next time the engine produced a strong SQUUEEEEEEK sound before stopping.. another attempt and it squeeked right after starting and died.. loud as hell.. (belt tensioning?, oil pump?)

also, every time i touch the gas pedal, it simply dies.. (carb issue?)

i know.. it is long.. but what do you think the problem are?
 
egres! i have some hesitation when pulling away and my dad told me it was probably due to the old dirty carb so you might just have a more extreme case of filth! try cleaning it out and see if it works.

good luck (Y)
 
thx guys, will try to clean the carb thoroughly.. it is literally black, so that could be a problem :D

btw, what exactly is the cause of immediate death after touching throttle? could be something with ECU, or is it only blocked jet or sth? when i open the choke plate manually while idling, it also dies immediatelly, so it looks to me like it doesnt get enough fuel..

does the idle fuel feed disconnect when you step on a gas even slightly? it would mean that there is a blocked jet somewhere i think..
 
had a look at it today..

took out all plugs (bosch super 4.. not that bad, right?), 1,and 4 were black, 2 and 3 too, but not that much.. cleaned them with a metal brush.. also sprayed carb cleaner into the carb, is much more shiny now..

this sorted the 400-700-400-700 periodic reving..

the biggest problem still remains, in wont run longer than 30 secs on first start, then 10-15 secs on next. (i've started it maybe 30x today).. on idle it runs very slow, but stable.. (atleast until it dies..).. when i push the gas only a little, it comes up to maybe 700rpm for 2 secs and dies.. if i step on the gas, it tries to increase revs rapidly but at 700-900 rpm it simply cuts off..

i am helpless now.. could this be something with the control unit under passengers seat?

i suppose that if the problem was with the fuel etc, it wont run faster than 700-900 rpm, but then it wont cut off completely.. i mean that if i stepped on the gas and released it, the mixture in the chambers should ignite at least a few times before stopping.. (hopefully you understand..)
 
so could it be due to the hoses then frank?
cos i would need to look at mine soon too aswell as the filthy carb!
 
sed5000 said:
so could it be due to the hoses then frank?
cos i would need to look at mine soon too aswell as the filthy carb!
Click to expand...

dunno shaun, if its dieing as soon as he hits the throttle then its probably megga lean for some reason (blocked jet/low fuel chamber level/fuel starvation etc)
a vacuum pipe fault/problem will largely only affect small throttle openings and low revs :)
 
ah this seems a toughy, i hate it when something goes wrong and you can never find the fault until someone points it out to you! grr

maybe start a checklist egres and tick em off as you go just to be on the safeside:

Carb:
Ignition:

as i dont know a lot thats all i have :down: but hope you get it running again soon!
 
thanks frank, it is something with the fuel..

when i literally soaked the filter in petrol, engine jumped on in a fraction of a second and ran fine. stepped on a gas and it went right up, faster than 4000rpm with no problems..

now the question is, if i want to sort it out or just spill the petrol on filter again and use the minute or two of time it gives me to get the car out of the garage..

i will check the fuel level in carb, hopefully it is in the middle :/.. i'd rather not disassemble it and correct it.. looked into the haynes and it is a hell of a job

earlier at the garage i was trying to find idle mixture screw.. does the 1.2 with ECU even have one? haynes has a picture of it, it is located near the bottom of the carb on the right side (when you sit in car).. in my 1.2, there is a brown metal part with two holes, positioned like number 8. lower one is slightly larger. problem is, that 1.2 has both holes empty, while haynes pictures a special screw in a lower hole.. wtf?

@sed, as frank said, problems with vacuum usually shows themselves on idle.. and the engine wont even try to run smoothly for a second or two.. i believe that the main reason is because the vacuum is highest (in fact, lowest.. i mean lowest pressure) when the engine is idling or decelerating.. when you will get to carb cleaning, it is of course good thing to look at the hoses, because after 20 or so years they will have cracks..
 
sed5000 said:
ah cool thankyou and thankyou again as the leds turned up today! (Y)
Click to expand...

no problem :) if you had some questions about connecting them or placing into reflectors etc, just ask.. few simple steps and you can connect it by yourself.. also, if you want to have better looking text, use "sketch paper" or how do you call it.. it is a semi-translucent/transparent paper for drawing, it wont block the light too much and it makes the words step out greatly..
 
another thing. sorry for spamming..

just reading haynes manual and found some interesting stuff.. (amongst other useful stuff)

E.C.C air-fuel ratio solenoid - could interfere with the mixture, making it lean?

throttle valve switch - engine dies when i press the gas.. also wont start when the throttle is open.. this switch opens only if the throttle is closed.. coincidence? maybe..

fuel cut solenoid valve - should disconnect the fuel when the engine is running above 2150 rpm, has temperature above 60 °C, throttle closed, transmission in gear and clutch engaged....

if there is something screwed up, and ecu thinks that it is a good idea to disconnect fuel when the throttle is open, the last two should be looked at..

page from manual..
24b583c.jpg
 
i try to go into this on the forum with my super s stuff and all this EGR/ECC stuff buts its all a bit scetchy .. my fuel air ratio solenoid seems to be past it now tryed to fix it carbs been apart loads but now i have to dissconnect the fuel are ratio solenoid valve or it just goes BORRRR cut out on revs ..
it was running ritch on the dyno when plugged in when it was being a bit iffy..

anyways ill be getting a new carb IE normal 1.2 one .. or a uprated carb/inlet setup
 
oh and thir is a screw but its got a cover on urs im guessing.. just drill it a bit and pop it out.. and thirs a screw behind it :)
 
hi again.. and thank you all..

today i got it out of the garage and got my frozen 1.0 inside.. after spilling petrol on air filter it ran fine again for good 5 minutes, so i decided to let it be for now and return to it when it will be warmer outside..

i suppose that i will try to start it with wet filter again and then rev it, clean it, rev it.. maybe it will get sorted.. if not, car is going to my friend who wants to add a roll cage, repair/replace engine and.... most probably die of frustration :D

thx
 

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