So I was told that if I built a engine in my garage and try to start it with a stock ecu by the way the car is na s4. That it wont start due to that the stock ecu wont read any compression and wont let it start. So I will have to hook up to a stand alone ecu or some kind of setup where I dont use the stock ecu to build compression and then I can use the stock ecu. So is it true or not?

 

Uhhh, where the hell did you hear that? The ECU has no way of even knowing what the compression is. Rebuilds usually have low compression at first since they're not broken in yet, and can therefore be hard to start. Some oil squirted into the spark plug holes and a bit of patience and you're good to go.

 

you need to tell whoever told you this to lay off the crack....

 

yea, i was wondering what the hell kind of info did you get. hopefully not someone trying to scam you into buying stuff you dont need. like the other guys said, dont talk to them about rotarys if they dont know em. also, please search for more info on how to rebuild a motor and how to break in the newly rebuild motor.

 

LOL LMFAO!!

in no way am i trying to be rude.. but if the stock ECU can read compression, i would think companies that manufacture compression testers go bankrupt by now..

 

What standalone measures compression, what a bunch of BS.

 

You can use the stock ECU with an aftermarket compression sensor. Its located in the charcoal canister. You can usually get them from yahoojapan.

 

Maybe that person was thinking of the MAF sensor?

MWA HA HA HA

 

Why does this **** come from? Where are the face palm pics?

 

okay i meant was that the stock ecu if it detects really pressure it wont turn on. And a standalone ecu does not detect compression at all thats why it can turn on a engine with low compression on. The reason I ask this cause i did tried with stock ecu for like foreverand then pop in my microtech and boom in 2 tries it cranked over.

 

Let me ask you this, where is the compression sensor in your engine ?

 

Rebuilt engines are hard to start for a while and you might get the car to start easier with a stand alone by pulling some fuel at start. But there is no such thing as an ecu that reads compression for these cars.

This guy is either lying to your face or he is a dumbshit who doesn't know dick about rotaries and opens his mouth like he does.

Your stock ecu should be fine.

 

Bottom line:

Your information is incorrect. Starting a fresh motor is difficult on a stock ecu but thats purely because your initial compression MAY be low and prone to flooding. Even that statement doesnt hold much water because if you built it correctly you would have enough initial compression to start the motor.

ECU has NO clue what the compression does. In fact the S4 ECU doesnt really have much of a clue about ANYTHING.

 

No.

-Ted

 

Would you have any idea why one primary injector is getting power to turn on an the other one isnt getting nearly the power? Id figure i would ask you cause you seem to know alot about rotarys. btw its a N/A s4 that i just rebuilt.

 

Either bad injector driver in the ECU or bad wiring.

 

Turn the ignition on and, place your negative on any ground and check for voltage at all the injector plugs. If you don't find the problem there check resistance between the other wire on the injector and its end at the ECU. If there is very little resistance on all of these, than it is a problem with the ecu.

 

Brake fluid in the spark plug holes works well, however think its a bit over kill for a fresh motor, good for getting those ones on their last legs going thou. oh it cause the engine to smoke a bit aswell.

 

always never wrong to do a push start. i think that's the safer-est way.