Need Help Going from Standalone Back to Stock - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

derass · 10-30-2016, 10:21 PM

Quick back story: Bought the car 5+ years ago with a stock SR swap. Ran damn near perfect. Upgraded to Haltech, 550's and a GT2871R. Now I've put the stock ECU, injectors, MAF and turbo so that I can sell the car.

Everything went pretty well, it's just that the car doesn't run exactly like it used to years ago when I got it stock. It's idling rich (10-12 AFR) and misfiring a bit when the engine speed is increased.

Is there some kind of re-learning process the ECU needs to go through? I had to reset the ignition timing. But how about the TPS? Or idle? Something else?

I'm thinking the car might need a boost leak test, because the Haltech used MAP so minor leaks did not make a difference. Being on MAF again, it does.

*brndck* · 10-31-2016, 06:48 AM

tps for sure needs to be checked. there is a way to adjust it while monitoring with a voltmeter. idle can be adjusted as well, but the misfire i would be concerned about. can you isolate it to one particular cylinder?

rawgarage · 10-31-2016, 10:52 AM

you reverting back to stock on your own? if not a simple tune would be easiest and a selling point for the new buyer... even with those parts listed...should find and fix any issues at the same time...

derass · 10-31-2016, 07:04 PM

Quote:

Originally Posted by brndck

tps for sure needs to be checked...the misfire i would be concerned about. can you isolate it to one particular cylinder?

I'll check the TPS, but I doubt that's the cause, with Haltech you simply use the existing closed and open TPS voltages and the ECU linearizes the area in between. The misfire is going to take some diagnosing. The injectors I put back in might have got mixed up by the tuner. They appear to be stock SR, but the 2 of the pintle caps don't match and one body is more faded than the others. Might also be the plugs, kind of fouled them up before I reset the timing.

Quote:

Originally Posted by rawgarage

you reverting back to stock on your own? if not a simple tune would be easiest and a selling point for the new buyer... even with those parts listed...should find and fix any issues at the same time...

I've found buyers don't want to fork over the cash for "finished" car. They'd rather build it one up them selves or just can't afford it. I've had far more success advertising the car with stock parts and a reduced price.

derass · 11-03-2016, 04:22 PM

Any more advice? I'll be working on the car tomorrow. Pull codes, boost leak test, checking sensors and such.

10-30-2016, 10:21 PM	#1
derass Zilvia FREAK! Join Date: Jun 2010 Location: Toronto, ON Age: 37 Posts: 1,182 Trader Rating: (0) Feedback Score: 0 reviews	Need Help Going from Standalone Back to Stock Quick back story: Bought the car 5+ years ago with a stock SR swap. Ran damn near perfect. Upgraded to Haltech, 550's and a GT2871R. Now I've put the stock ECU, injectors, MAF and turbo so that I can sell the car. Everything went pretty well, it's just that the car doesn't run exactly like it used to years ago when I got it stock. It's idling rich (10-12 AFR) and misfiring a bit when the engine speed is increased. Is there some kind of re-learning process the ECU needs to go through? I had to reset the ignition timing. But how about the TPS? Or idle? Something else? I'm thinking the car might need a boost leak test, because the Haltech used MAP so minor leaks did not make a difference. Being on MAF again, it does. Last edited by derass; 10-30-2016 at 10:51 PM..

10-31-2016, 10:52 AM	#3
rawgarage Banned from the Marketplace Join Date: Oct 2007 Location: h o u s t o n Age: 36 Posts: 5,986 Trader Rating: (75) Feedback Score: 75 reviews	you reverting back to stock on your own? if not a simple tune would be easiest and a selling point for the new buyer... even with those parts listed...should find and fix any issues at the same time...

11-03-2016, 04:22 PM	#5
derass Zilvia FREAK! Join Date: Jun 2010 Location: Toronto, ON Age: 37 Posts: 1,182 Trader Rating: (0) Feedback Score: 0 reviews	Any more advice? I'll be working on the car tomorrow. Pull codes, boost leak test, checking sensors and such.