SR20DE+T Rough idle when warm

AaronB13 · Postby **AaronB13** » June 14th, 2012, 10:58 pm

We recently turbo-ed a silver top SR20DE (highport), and began experiencing some problems with the idle. The car idles perfectly when the engine temp is low, but as soon as it warms up it begins to hesitate and stall. Thats one problem, the other is that when driving, the car loses power at around 3-5k RPM, HOWEVER: when the TPS is disconnected, the car rev's out clean, no power loss, but the idle problem still persists. I checked the TPS and its fine, voltage output is linear, even tried a new one just for trying it sake and the same problem exists.. any help? 8-)

UPDATE:

After installing turbo injectors and pump, using an HKS Super AFR for fuel management, the car runs well while driving, however there is still a rough idle/hesitation sometimes. While this happens, my wideband reads around 16 - 17 (full lean). What can cause this periodic hesitation? Sometimes the car idles well and the wideband reads around 13.5 - 14.5 which is normal.
Coolant temp sensor seems to be okay, MAF voltage reads well as compared to the FSM, cleaned out the idle valve and throttle body but to no avail..ideas anyone?

haydn28 · Postby **haydn28** » June 15th, 2012, 12:15 am

check for boost leaks and leaks from turbo to maf , the MAF voltage could be reading too low due to leaks resulting in a lean afr on idle , btw when the coolant temp is cold , the ecu runs the engine rich so it will idle well until it heats up . hope u are using a form of engine management and sr20 370cc injectors at least . good luck

THE SYNDICATE · Postby **THE SYNDICATE** » June 19th, 2012, 11:46 am

Clean ur maf....see if it helps!

* haydn,still saving for meh emanage

*

AaronB13 · Postby **AaronB13** » June 24th, 2012, 5:07 pm

Put in some 370cc injectors, Walbro pump, using HKS Super AFR as a temporary fuel management system, things have drastically improved! Just a bit more tuning and everything should be in order, thanks for the replies guys

AaronB13 · Postby **AaronB13** » July 7th, 2012, 8:41 pm

THE SYNDICATE · Postby **THE SYNDICATE** » July 25th, 2012, 7:27 am

Bro,i think u should ditch that afc and get an emanage blue or ultimate!

AaronB13 · Postby **AaronB13** » July 25th, 2012, 7:56 am

I agree, but thats the least of my problems right now, the car runs well with it on 7psi boost for now. I will eventually upgrade to an emanage when i'm ready to go up in power but my main issue right now is the idle problem, and for sure its not related to the AFC. I dunno what to try again :/

THE SYNDICATE · Postby **THE SYNDICATE** » July 25th, 2012, 9:10 am

i notice u didn't say anything bout ECU? u still using the De ECU?

AaronB13 · Postby **AaronB13** » July 25th, 2012, 9:33 am

figured u would ask that, i got a DET ECU and airflow borrowed, didnt even need to use the AFC with that set up (as expected) but still had the idle problem... this problem existed even before the engine was converted to DE+T though, ever since it was bought NA from bamboo.

THE SYNDICATE · Postby **THE SYNDICATE** » July 25th, 2012, 11:38 am

Three things affect idle... the TPS, the CTS and the MAF!
Something have to be faulty along those lines!

what about those sensor connectors... are they in good condition? check and see if it has any broken wires around there!

AaronB13 · Postby **AaronB13** » July 25th, 2012, 11:32 pm

well for sure the tps and maf are fine, i wasnt too sure about the cts but it seemed to be outputting the right voltages..i'll double check the wiring to be sure, will let u know how it goes, thanx!

THE SYNDICATE · Postby **THE SYNDICATE** » July 26th, 2012, 6:26 am

no probs man..

my car was down for bout 8 months. when i got it online i had some dread idling issues.(that was when it was DE) when coming to a sudden stop it will stall, sometimes cut off,etc.

i changed the CTS and the problem was gone..

*i still have the stalling sometimes,but that is due to it being DE-T now with an atmospheric blow off and not recirculator! (spelling)*