First it cranks and takes about 3-5 seconds to start. Then dies early, and may require restart. After restart the rpm goes up and down (between 2000 and 500 rpms) and dies again ... Finally when the engine warms up everything is fine.
The thing is that the car was tuned about a year ago and everything was fine, the engine starts at the 3rd turn, it idle at 1500rpm while warming and then idle at 950 on warm engine. This new behavior started about a month ago, and I don't understand why... Nothing new was added to the car..!!just changed oil and filter, and two weeks ago the sparkplugs..!!

My mods are :
1000cc PTE Injectors
RNR 35R turbo kit
272 HKS cams
Twin in tank Walbros
and a bunch of other stuff to make it go faster..!!

Please help..!!

 

pressure test the engine/ IC. a vac. leak will cause it to act crazy.

 

I don't think this could be a boost leak, since I able to hold 30psi from 5000 to 8000 rpm in third gear... but I will check anyway.

Thanks,

 

no codes thrown?

 

Codes... what codes..?? with the AEM EMS...??

 

OK... my car is going from bad to worst ...!!!

I haven't had the chance to play with the settings, so, nothing had been done yet. Now, everyday is taking longer and longer to start..!! I really don't know why this is happening .. One thing I had noticed (and is very annoying) is that while cruising, the car is running extremely lean, at low RPMs and at idle also...
Maybe this is the cause of all the problems... and is getting worst and worst each day...

Any thoughts ...??

 

test your iac. i just had this problem and fixed it by swapping out iac's

 

Sorry for the Q... but, what is the IAC (Idle Air Control..?) and how can this make the car go lean.....?

Thanks,

 

did you find a solution? im having these problems now

 

Oh yes, it was a bad MAP sensor..!! Just replaced with a new 5 bar AEM MAP sensor , put back the previous settings and everything is good again...

Hope this helps...