I recently had my ap1 tuned with a haltech pro ems by some guys down here in Perth called C-Red Tuning running a spoon n1 exhaust with a test pipe, otherwise stock. After the tune the car took many cranks to start up and one day would not start at all when cold, which I then ended up having to tow start the car.

A few days after this it started misfiring and eventually ran on three cylinders, and I took it back to the tuners where they replaced the spark plugs which fixed the issue, however the cold start issue has not been fixed and the car will take a long time to start if at all cold. The car did make around 10 - 15 more hp atw but is very rough and seems to backfire every now and again on low rpms when shifting. When reconnecting the stock ecu the car starts no problem and runs fine.

So I'm not sure if I have a faulty haltech or a bad tune, thoughts?

 

Tune for sure, I know some of these ECU's will take a higher voltage to start (AEM V1) but it wouldn't cause backfires. Is this place well known? And do they have a lot of experience with S2000's?
You could always put the stock ECU in and then see if these problems persist...

 

Thanks for the reply, yeah these guys are well known here however most of the cars they tune are silvias and gtrs etc, basically all forced induction cars. I would put the stock ecu back in however I don't like the fact that I've wasted quite a bit of cash just for it not to start, and the car does pull harder with the haltech, however I will contact the tuners again.

 

I was saying just put the stock ECU in for the time being and see if your issues continue. If they go away with the factory ECU you'll know it is the tuners (: at which point I'd take it somewhere else.

 

Just as Alex said. put your stock ecu on, and run car for a day to let the ecu relearn. Then check to see if the problem persists.

but it sounds like the car isnt getting enough fuel.

 

He said he popped stocker in and it started right up.

What inj. You running?
So after its at operating temp it starts right up normal like?

 

Stock injectors and at running temp it still takes more cranks than normal to start (around 4 - 5) but definitely starts quicker than cold.
And yeah stock ecu is absolutely fine no problems, doesn't drive rough, throttle response is back to normal as well.

 

Haltech will be longer to crank than stock. That's normal. Mine takes a few cycles some times too. The tuner might not have enough file in the startup maps causing it to take longer too.

Back fire in low rpm is probably too much fuel at that position.

You can get the haltech CAN Wideband and it will self tune to a target afr and if the sensor fails will fall back to the originally tune.