Thread: HELP!!!!

Okay, so im to the point where I'm about to throw in the white towel. (Not literally) But about to call it quits for a while. LOL. So anyway, I recently installed a brand new 255 Walbro fuel pump, along with some 370CC injectors, Z32 MAF, and a JWT ECU re-programmed for all of these items plus turbo. So after the install, my car runs really rough, like it won't go past 3k rpm, and when it idles, it idles like its huffing and puffin for air, then dies. I did some research and some say its a bad ground when I spliced into the harness (3 wire to 4 wire). After stripping the harness apart again, I re-wired correct according to the JWT Z32 diagram for the B14. Everything was twisted and electrical taped tightly so that no water can get into the splices. And so it looks cleaner. Car idled solid and the car ran fine. I drove it around for 15-20 minutes no problem. Then I came back 5 hours later and tried starting it up and of course it won't let me go past 3k rpm again. This time, I couldn't even drive the car. I would hear popping noises coming from the pop-charger like the engine is misfiring. When I turn off the car, then start it back up, I can rev it past 3k but then once I start driving, it drops below 1k then starts to pop again.

Anyone ever had these issues? And if so, how did you fix the issue? Codes that came up was P0100 (MAF malfunction). I've researched how to troubleshoot bad MAFs and one of the ways is to pull the MAF sensor when the car is idling and if the car still runs, that means the MAF is bad, if it dies, then the MAF is still in good condition. Is that correct? Any help would be greatly appreciated! Good weather is finally near, and I would like to get this beast back on the road.

Yeah sounds like it could be the maf. Did you check continuity from the maf pins to the ecu plug? I'd also solder the wires not just twist them. You can also check the maf voltage at idle should be around 1v iirc

Sent from my SM-N900V using Tapatalk

*ALWAYS* Make a proper wire connection - twisting wires and electrical tape in not a *PROPER* wire connection.

If the MAF was mis-wired you may have damaged the MAF Driver inside the JWT ECU.

Is your MAF setup as a draw through or blow through?

A pic of the engine bay helps allot.

As mentioned, it is a MAF problem. Had this same code (P0100) a month ago (N/A application).

In regards to the wiring, there is no problem with twist connections, provided the wires are clean and the connections are tight. I seal twist connections with electrical tape, followed by 2 layers of heat shrink tubing. The second layer should be longer than the first. A good twist connection will be stronger than a dirty or weak solder connection. I don't bother soldering unless making connections on an electrical board or similar. If there is proper continuity, then there is proper continuity.

If you are positive that the wiring is proper, the MAF ground is good and continutiy exists between all connections, you can then look at other areas. (*Don't forget to check that the engine harness has a clean and secure engine ground connection*)

Have you recently oiled the air filter? Try this and see what happens...

1) Check all connections for proper continuity and voltage.
2) Check MAF voltage with ignition on (car probably won't idle to warm-up condition)
3) If all seems good so far, remove key from ignition and disconnect the negative lead on the battery.
4) Remove MAF harness connector and check the harness and MAF pins for damage and debris.
5) Remove hose clamps & MAF from car. Clean sensor hot wire w/ CRC MAF cleaner (follow instructions on can)
6) Let MAF dry completely and reinstall, making sure all hose clamps are tight and NOT leaking.
7) Re-connect the MAF harness and make sure it is properly and fully seated.
8) Check to make sure everything is how it sould be
9) Re-connect negative lead on the battery (the time disconnected should clear the P0100 code)
10) Start the car and see what happens..

^^^^ Bad advice. A twisted pair is NEVER a proper repair. Butt connectors are ok for a temporary fix, but a solder repair is a lot better IF you know what you are doing. I will also argue that when you twist those wire together, you are getting oil on the wire from your fingers, this will cause corrosion. This can be prevented through the heating of the wire during soldering.

What's your timing at?

Should be 15* degrees as per JWT, if not stated otherwise. My setup backfired, ran rough and didn't boost 'right' til timed correctly.

I have been wiring electronices for many years and I have NEVER had a problem with a proper twist connection. As I said "there is no problem with twist connections, provided the wires are clean and the connections are tight". When I wire, I use powder-free latex gloves. It isn't absolutely required.

Most people don't know how to properly solder and as such, their connections are dirty and weak. Clean and properly sealed twist or butt connections will generally be better in this case.

Skin oil on the wires is NOT his problem here. I guarantee that.

No one is saying that skin oil is his problem. And that is good you have not had any problem. However, in any profession that I can think of off the top of my head, aside from house elec, twisting the wires is never "ok". Plain and simple bad advice, and two other people have already posted stating the same thing. And I can guarantee a professional mechanic will laugh you out of their shop if they saw twisted connection in a wiring harness.

Skin oil is not ever going to be a problem (in the car's lifetime) on a twist connection, on a harness for a sensor. Not at (120V household electircs and certainly not for a 12V automotive application). As I said, clean connections are clean connections. Resistance is a differnt story but once you break the original solid wire, you have changed that factor anyway.

I never said a proper twist connection was the be-all and end-all for wiring connections. I said it would be more than fine for him. I absolutely stand by that advice! Does the OP solder? Is he really skilled at it? Good enough to have a soldered connection in a hot vibrating engine bay without any fear of solder crack? I recommend twist connections (to most novices) in the engine compartment for just those reasons. A properly done twist connection WILL be better than a brittle twisted, hooked or straight solder conection. Also, you will not have to worry about corrosion on the wires if you properly prep them. Fresh cut-back, clean wires and a proper seal.

You are picking at straws here, that don't exist. If I saw a professional mechanic (who was charging in excess of $100/hr for electrical work) do twist connections and seal with just tape, I wouldn't be happy with that either. If the OP was a professional mechanic/wiring expert, he probably wouldn't have made this thread.

I appreciate your right to having an opinion, however, I absolutely stand by my instructions and the advice is not bad! A proper twist connection will never be his problem here! I never at any point in this thread said it was the best or the only method for carrying electrical current. The key to the longevity of a twisted connection centres around proper wire prep (as I mentioned before), a tight braid with fully intact/non-brittle wire, then sealing with electrical tape and minimum two layers of heat-shrink tubing in staggered length (long/longer). A strong connection will be a good connection.


If we are talking about by-the-book, 100% percent, absolute best wire connections...that belongs in another thread.


O.P. - Good luck.

http://www.nicoclub.com/FSM/Sentra/1996/EC.pdf
Start at page 93. Let us know what you find. Make any wiring repairs the right way.