Need help with idle issue

btwilson86 · 11-22-2010, 12:57 AM

As usual, check for codes (even if the CEL is off).

I'm thinking either faulty Idle Speed Control valve, possibly vacuum leak. Check the TSRM for testing procedure of the ISC, and listen around the engine bay for vacuum leaks with the engine running. I believe an out of adjustment TPS may also cause this issue, testing and alignment procedures are also in the TSRM.

MA70-3.0GT · 11-25-2010, 01:19 PM

Yep possibly any of the above, but also could be a fule pressure issue if it used to be worse on low fuel. Have you changed the fuel filter/checked fuel pressure? Could be a blocked filter with sediment from running low or failing pump/resistor.

11-22-2010, 12:57 AM	#1
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	As usual, check for codes (even if the CEL is off). I'm thinking either faulty Idle Speed Control valve, possibly vacuum leak. Check the TSRM for testing procedure of the ISC, and listen around the engine bay for vacuum leaks with the engine running. I believe an out of adjustment TPS may also cause this issue, testing and alignment procedures are also in the TSRM. __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

11-25-2010, 01:19 PM	#2
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	Yep possibly any of the above, but also could be a fule pressure issue if it used to be worse on low fuel. Have you changed the fuel filter/checked fuel pressure? Could be a blocked filter with sediment from running low or failing pump/resistor. __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!!

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