JS4KX

sleeved/boosted JDM gsr 9:1, type r head p&p etc, pro 2 cams, hondata s300 w/ CPR...

Hardly drive car as it's an enjoyment/race car for the wife and I. Well, last week we took it out for a cruise and 1st 15 minutes car ran fine, then started wanting to stall. Had to hold throttle slightly to keep car running. When I got home, I held throttle at 3,000 RPM, slowly lowered it until it wanted to stall. got to around 2,500 and it would drop to about 1,100 and then go back up to what I was holding at... If I let off any more car stalls. Per a recommendation, changed the plugs, and intake air temp sensor. Well, changed those, same problem. Adjusted TPS sensor, per datalog TPS was at 2% when throttle closed, adjusted that to 0% by loosening tps bolts and rotating while watching tps % on datalog. After that, same problem, replaced tps sensor, same problem. Car will idle just fine when cold, once warms up car will stall unless i hold throttle... Car has Mustang TB, no IAC, AEM 5 bar map and wideband. Can email datalog... Please help.

Thank you

FYI, car originally tuned by Evans, car was running fine and strong for 3 months so I think something went wrong somewhere...

JdmR-ek

Clean iacv

JS4KX

Thanks for the idea but ufortunately car has no IAC...

LTCxD2B

What's the air fuels at idle when hot?

JS4KX

14.6 cold, 13.4 warm... 92oct w/e10 in case you were wondering...

LTCxD2B

Might be a little too rich and or isn't getting enough air down low to stay on ... Is there like a throttle plate screw to hold the plate open just a hair and what about the idle air adjustment screw?

JS4KX

there is a throttle plate screw, which i turned up to hold throttle plate at 6%, roughly about 2,100 rpms... same thing, idles great cold, once warms up to about 110, starts surging, and eventually stalls. when restart, noticed hard to start, and when starts lots of fuel smoke...