strange spark problem
 

first off would like to say hello to you all...... now the problem

right i have a 97 sti, with the single coil pack on the top center, the engine melted a piston due to running lean on the fuel pressure, so i bought another sti engine, (same type), swaped them around, went to fire it up and she sparks twice then no more, wil turn over and over with no spark, but gives off 2 sparks on the initial turn then no mre?? ive changed the coil pack, and all the relative sensors but no joy, changed HT Leads and plugs, stil no joy, immobiliser it kicking in as normal, as when you turn it off the fuel pump and igniton kick in.
Wen the engine was first put in she ran for about 15 secs before cutting out dead and then sparkin twice and not continuing to spark? im out of ideas on this one, any one had similar problem or kno a poss cure,

im running apexi managment with fc commander, but im sure that wouldnt cause this???

please help!!!!!!!!!!!!!!!!!!

any idead any one????

As you said,lean due fuel pressure on your old engine.Have you check if your fuel pump is running with ignition key turn to ON.Suggest you check your fuel pump.

hi yes, once the immobiliser is turned on, you can hear the fuel pump kick in and the pressure on the gauge goes streight up?? also would that cause it to spark twice then no more?? this one is really bugging me now lol

sounds electrical to me ie wiring to coil pack ect.. could you have damaged/misplaced a wire/connector on the engine loom when engine replaced also did you use a different engine loom that came with replacement engine if so it could have the fault poss????

same loom being used, have taken the engine out and checked all the wiring and tryed another coil and still same, could the ecu be to blame? i have a clifford alarm as wel, but the imobiliser is turning off as the fuel pump is kicking in as wel as the dash lights??

taken the engine back out, checked the loom and no problems there, gone over everything twice, checking with another sti, i.e swaping sensors over, coil pack etc and still the same, sparking twice then no more on all cylinders? its really buggin me now as to wat it is? any one know about the clifford concept 650 alarms~? could this be causing it?? the immobiliser is switching off i think as the ignition lights are coming on and you can hear the fuel pump kicking in?

also the only other option is the ecu? i have an apexi ecu and fc commander unit etc, but surely that wouldnt make a difference as its mapped and should matter wat engine its sending the info to?


any help would be much appreciated as its really annoying me now lol also any one know any good scooby auto electricians that i could call to get some ideas??
cheeers in advance

cj

this sounds a strange thing but just had this problem 2 days ago. see if the car will start with a bump, ie been towed.
the problem i encounted was a 99 blew a piston an partially seized the motor, but the customer was trying to start the car after it died. when the new motor was in the starter had enough to turn it over but not enough speed to make the crank sensor give a strong enough spark. new starter cured it, weird i know. :wonder:

I had the very same problem recently mate! I like yourself checked all the wiring, changed lots of sensors, still no joy. I then decided to check the timing and hey presto the belt had slipped a few teeth and the timing was all to pot. This will send the signal from the cam pulley to the sensor wrong and the ecu cant trigger the ignitor hence initial spark then nothing!

It seems so obvious now to check ther timing first lesson learnt and 2-3 days lost lol.

weve checked the timing and thats fine, also the engine is turning fast enough to start the car,
we tryed swapping the sensors round just to check they wernt round the wrong way etc, the pressed the imobiliser button on the alarm and the fuel pump kicked in, but didnt stop, now the chamber has filled with petrol so wont crank over,
but im thinking if the pump didnt stop, possible ecu??

is it the same ecu from the old engine to me sound like an ecu problem and its putting everything to pot it could be fried!!!!!

More likely the trigger on the crank gear has been knocked out of line in relation to the crank angle sensor or perhaps it has the wrong gear fitted with the trigger teeth in the wrong place.

OR ditto the cam sprocket in relation to the cam angle sensor.

Quite common for us to see those out of shape especially as the crank gear needs a whole load of levering to get it off.

Have a close look at them.

David APi

Agents for Simtek, the most exciting new Ecu for years

checked all the sensors and there sitting fine, going to try and get hold of another ecu 2 try that now? otherwise were stomped again grrr

have you got or know someone with fc datalogit (apexi fc software)

might be worth saving your map, initialising ecu to go back to base map and try that.

unfortunaly i dont know any one with one of them?? what would cause the ecu to fry then, i would think an apexi ecu would be quite tough? and one know wer i can get a stock etc for a 97 sti ra?