1985 GMC 4x4 LS Motor Swap, tons of pics! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

jon75 · 06-09-2013, 03:54 AM

Could be a bunch of different things, almost all of them sensor related. It could be a cam or crank sensor. When those go out, the computer goes into a backup mode with known good parameters that it uses to make the engine run. If the problem persists too long, it will go into limp mode, resulting in limited fuel delivery, throttle engagement and spark timing. If you had the trans with it, it wouldn't have gotten out of second gear.

I sure hope you have the diagnostic link connector hooked up in your truck somewhere....otherwise you are going to have quite a fun time testing all the sensors.

06-09-2013, 03:54 AM	#17
jon75 Registered User Join Date: May 2013 Location: Tustin, CA Posts: 77	Re: 1985 GMC 4x4 LS Motor Swap, tons of pics! Could be a bunch of different things, almost all of them sensor related. It could be a cam or crank sensor. When those go out, the computer goes into a backup mode with known good parameters that it uses to make the engine run. If the problem persists too long, it will go into limp mode, resulting in limited fuel delivery, throttle engagement and spark timing. If you had the trans with it, it wouldn't have gotten out of second gear. I sure hope you have the diagnostic link connector hooked up in your truck somewhere....otherwise you are going to have quite a fun time testing all the sensors. __________________ 1975 GMC Sierra Grande K25HD 350-4BBL 4sp LWB 2009 Infiniti G37S Sedan w/Stillen sway bar kit & K&N Typhoon dual snorkel intakes ASE certified for brakes, electrical diagnostics and heating and A/C & EPA certified in R12 and R134a



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