s14 sr wiring issue? Hesitant Idle and btwn 4-5k RPM

[Phoenix4987]

Posted in the wrong forum before. So here goes round 2.

Hey what's goin on everybody? Just came back from deployment and got a s14 front clip and went to SR20 store in Gardena, CA to do the swap in my s14. The swap is complete, but there were some problems that Marco associated with the wiring in the car itself and not from the SR setup. After a few weeks, Marco is calling it quits. Kinda brings me down, I had a lot of faith in him but hey, shit happens.

My question is, what are some shops or maybe even some of YOU can help with this issue near Camp Pendleton/San Clemente area. I don't mind driving or having my car trailered to a shop who can diagnose the issue as follows:

The engine runs good some days and others it really hesitates (misfires) on idle (will shut off some times) and through the 4k - 5k rpm range. The ECU, ignitor chip, coil packs, spark plugs and the fuel injection harnesses have all been replaced. The timing has been checked, so have all of the grounds and all of the power for the ECU. The check engine light comes on, but it won't drop any codes.
The MAF was never changed.

There was some janky things that the previous owner did. He said someone was doing some work and grounded out the wiring harness. So he replaced the fuse box and also the fender harness. The fender harness came from a "96 s14 obd2." The chassis is a '95, don't know if there's any issues there.

I strongly agree with Marco that the issue is with the main harness off of the car itself since I redid a lot of other dumb shit that the previous owner did. Who is good with these issues? The car runs, I just want it to run smooth so I can really enjoy my sr. Thanks.

[Phoenix4987]

Here's a video of it at idle. With and without the mag plugged in.

S14 sr idle problem - YouTube (http://youtu.be/qejUZSTyYQ0)

Setup:
S14 SR
Blitz FMIC
HKS SSQV BOV
Apexi Intake
Mishimoto Rad
Nismo thermostat
NGK Spark plugs
Stock injectors
Stock ECU
Walboro 255 pump
Apexi N1 exhaust

There's other shit, but these are the only parts that will affect the running of the engine. As in a clutch and flywheel, etc.

[Phoenix4987]

Cleaned MAF, IACV. Put in new fuel filter. Unplugged o2 sensor to see if that would do anything. Nothing.

[Phoenix4987]

Regapped spark plugs to .030 (+/- .01-.02) and it seemed to idle a lot better. The plugs I found in there had no fucking gap! wtf! But! under mild acceleration would sputter and flash the check engine light. Gonna go get spark plugs and a new MAF. But was wondering if .030 is the stock gap? I've been reading a lot and I find a new answer everytime I look for the gap size. Any help on this would be greatly appreciated. I'm trying to do all I can by myself before I send it into a shop again.

[Phoenix4987]

Ok here's the results. I got grey/black. white in the middle. and the red striped.

Grey/black .004v. Throttle doesn't affect.
White in middle .237 at closed throttle, 3.755 at wot.
Red stripe 5.133 steady

[Phoenix4987]

adjust tps. couldn't get it exactly at .45 throttle fully released, but near there. at full throttle only got around 4.0-4.1v

on the maf. voltage checks at idle, but signal voltage is kinda high at around 14.v.

will idle fine now. however, drive it for 5 minutes and come to a stop and car will want to die. still misfires sometimes at idle and above a certain throttle percentage. wot not even possible. will misfire and jerk before you even get there.

what are your thoughts? i could use some serious help.

[Phoenix4987]

Welp, my findings:

Threw in new plugs and a fuel pump on a whim and problem solved. Can finally enjoy my sr now. Hopefully this thread helps out someone cause I read so much shit trying to get to the bottom of this. But yup. Turns out my walbro was dying/dead and I just picked up a stock one from the auto parts store to see if it would work and it did!

So if your sr starts missing at wot and throws on the CEL while it's doing it, and then goes away when you back off the throttle. Check your fuel pump!