RB25 S14 Wiring Woes

[FinkenS14]

OK, so today I decided to wire in my wipers for my RB since the snow is starting to come in.

Turn the key on, wipers work...

We wired everything up, and then go to start the car and it sounds really odd. Kinda a rough idle. It was cold out so the car was idling a little higher. Drove it the block to my house from my friends where we did the wiring and let the car sit and idle while I pulled the ecu and dash plug back out. While I was doing this idle was changing the whole time. It'd get real rough, and stumble, and then catch, and then soemtimes idle perfectly normal, it was only doing this when i would move wires around...

I kept trying to mess with wires and then it fianlly just stumbled and died.

I tryed restarting the car but nothing. Just cranks. Fuel pump IS NOT priming.

So far Ive disconnected the wipers completely to rule that out.

So i take out the fuel pump fuse, good. Crank the car without it in a few times. Put it In, crank more, still nothing.

I go through every single wire that I have (from doing to conversion), and every one is good. Take the top off my ECU red light comes on with key on, and no burnt spots or anything that looks peculiar.

Could one of my relays gone bad or soemthing, or soemthing worse?

Any ideas/advice

thanks guys
Modified by FinkenS14 at 6:28 PM 10/8/2009

[FinkenS14]

I searched and only found people directly wiring the fuel pump to the battery

[FinkenS14]

OK so I just went out and messed with the car some more.

I had a spare relay and i switched it with my fuel pump relay and nothing.

And weird thing

After I turned the key off one of the relays kept clicking on the passenger side. I heard one of the relays clicking. and the ECU light stayed on with the key totally out of the car.

It kept clicking. Id take the relay out, and itd switch to the other relay and start clicking. Put that reelay back in, and itd switch back. Red light on the who0le time. Only way to get it to stop was taking the positive side of the battery off.

What the f*** is going on.

Only thing that i can think of is how I have my power for my injectors hooked up. With an RB25 is an S14 I was told you have to give them a key on 12v source so I tapped into the black/red wire on the ECM relay...

Any help guys?

[FinkenS14]

Found my problem out

Wiring pin in the dash plug for the fuel pump was way loose. Fixed it and the car started to idle, but still like it had a miss.

Started messing with wires and when I came to my injector wires by the ECU and moved them around, the idle cleared up. But it wasnt a reliable idle.

So I turned off the car, peeled back the tape from them out about 4 inches from the ECU and the idle is totally normal now no matter what.

Weird huh? I know there might still be a problem. Anybody got any ideas lemme know.

BTW, might add, my injector harness had been cut when I got the motor, so I had to repair it...

[spolitte]

Hey, I am having a similar problem on my s14 with an rb20det in it. Originally what was happening was pretty similar to what happened with your rough idle, except the car would also drive poorly at random times (i.e. would drop in revs, have no throttle response etc). I found that when I twisted the ecu around it would sometimes fix the problem. Since then, I have gotten an new AEM ems, and the problem multiplied when the stock ecu was pulled off. What happened when the AEM was installed is that when the key was turned on either a) the fuel pump wouldnt prime, or b) the injectors would not get power. This also depended on which way the AEM was twisted. So, back to the stock ecu, but the same problem now on the stock ecu; one way no fuel pump, the other way no power to injectors. At this point I think the connector on the whole harness to the ecu is just worn from being connected/disconnected/reconnected so many times; so, I am now waiting for a new/used connector coming in the mail so I can go switch it out with the old one and hopefully get the car running again so the AEM can finally be tuned!

[FinkenS14]

Hmmm thanks man! Nice to finally get a reply. Ill let you know and update.

I am also having no throttle response issues sometimes, but who knows it could have been becasue of the loose fuel pump wire.

Id like to just get a whole new RB harness but its kinda hard to come across a Series 1 harness ya know

[sickness14]

you should PM Carl H, search for him. he's great at wiring RB's into S14's. he did my harness. cool guy too

[spolitte]

Yeah, from what I've heard and have picked up from talking to him, Carl H is a G when it comes to the wiring on rb240's. When my wiring started going funky I was pretty worried thinking I had a cross or short somewhere in the wires and would spend hours finding it. I was kinda worried that I'd have to have a friend in Asia track me down a new rb20 harness or that I'd have to send mine to Carl to have him go over it from top to bottom, but both of those options would have cost 300+. So, I had a buddy at a shop go over the wires with a multimeter looking for the issue (hoping we could find and fix it). Thats when it was diagnosed as a faulty connector from the harness to the ecu. As I mentioned, I'm still waiting on the replacement connector, which should get here on Monday. As soon as it comes in the mail, up to Fort Collins for me to go cutting/splicing/fixing some wires. I'll let you know if this solves the issues when I go put it in.

[FinkenS14]

Id do that but Im kinda short on gas right now.

Im thinking my repair on the injector ahrness towards the ecu is my culprit...

[spolitte]

Hey, was up in fort collins this week, and my friends helped me repin the whole ecu.... that was fun. Anyways, we get thru repinning this thing, run all the plugs back to their sensors and everything, plug the battery back in and go to start the car, but guess what, when the key is turned to the on position everything in the car turns on, except the fuel pump doesnt prime, which is exactly what part of the original problem is and why we repinned it. Well, a about 1 hour, multiple cigarettes, and even a few random loud and obscene screams later we get back in the car and took a look at the harness again. This is when the kid who basically repinned the whole thing realizes that the white clip coming off the harness (about 12" from the main connector and goes into a plug in front of the passanger door) was not connected tightly. By the way, on first inspection this clip is designed really stupidly because of the way it latches down to make a 'tight' connection. You will know which clip it is when you look at it. Anyways, many of these wires on this connection are already clipped from the rb20 swap, but the problem was that the crucial ones that are still hooked up (i.e. the fuel pump relay) were not getting a proper connection. Sometimes when jiggling this clip around and pushing it in we could get the fuel pump relay to click repeatedly and the fuel pump would try to prime when the ignition was on. Well, we finally got that clip plugged in tightly, the fuel pump would prime correctly when the ignition was turned on. Well, one turn of the key later and SUCCESS!!! The car turned on, even if only for a second before it died, which is probably because of the new AEM ems with only the base maps and probably even uncalibrated timing from all this nonsense... Luckily the car is sitting in the shop this weekend and waiting to get tuned on the dyno! Well, I hope that my wiring issues are solved for now, and I hope this helps you with your problem Finken if you haven't already taken care of it. Keep me updated how yours is coming tho cuz its always nice to have the experience of others when trying to trouble shoot wiring problems, or any problem for that matter