PIH harness in 94 check engine light

**blksunshine88** · 03-09-2009, 11:49 AM

I have a 94 gt with 19lb inj gt40p heads e-cam tfs track upper/lower 70mm tbody stock mass air meter eliminated egr (installed that stupid plug thing from ebay since the resistor trick didn't work)
I just installed a pih harness ( triple checked my wiring) with an a9l i'm getting codes for evp and something about my neutral safety switch voltage any help would be much appreciated- thanks, Greco

**torqueboxer** · 03-09-2009, 06:14 PM

Mike look into summit part # hly-o-85751 this should fix this problem

**blksunshine88** · 03-09-2009, 06:16 PM

haha thanks ben no carb until 351

**blksunshine88** · 03-09-2009, 11:41 PM

update- car idles fine with clutch pedal released, when pedal is at floor idle surges then falls off neutral safety switch differences between fox and sn95 cars?

**blksunshine88** · 03-10-2009, 10:37 AM

no help?? paul where ya at? lol

**Killercanary** · 03-10-2009, 11:48 AM

Greco, I wish I could help you but when it comes to the stuff you asking about I don't know the answer. I was never a fan of the PIH so I never spent any time learning about it. I don't know if there are any EEC parameters that vary based on the neutral safety switch between the A9L and the T4MO processors. I would think it'd idle better with the clutch disengaged rather than engaged just because there is a tiny amount of extra load on it when it has to spin the clutch disc and transmission input shaft, but I've never noticed a difference in either of my 94-95's.

What is EVP? Evaporations canister?

**blksunshine88** · 03-10-2009, 11:45 PM

exhaust valve position sensor (EVP)
i seem to have figured this one out unplugging the clutch position switch seems to have fixed the idle problems however i'm now getting a 02 sensor code saying always lean im takin the harness back out and quadrouple checkin wiring if everything is fine welcome back T4M0! lol

**blksunshine88** · 03-13-2009, 10:33 AM

had o2 signal return wire in pin 28 should have been 29 , i love the swap all driveability issues are gone!!!!! sure i left a few horses on the table but the whole swap only cost me 100bucks!! beats 350 for a tune

**blksunshine88** · 03-13-2009, 10:34 AM

paul EVP is EGR Position Sensor

**Killercanary** · 03-13-2009, 11:34 AM

Thanks Greco. I knew it couldn't be an exhaust valve position sensor as we don't have them, but the EGR makes sense. I'm glad to hear that you got it all figured out. How did you manage to do the swap so cheap?