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ok here we go. Today it was nice so I decided to work on my car.

1st I wanted to diagnose why my horn wasnt working. Ends up being that the relay is bad.

2nd I wanted to bondo my fenders. Thought that I didnt have any hardner so I skipped that task(later found the hardner)

3rd Heat shrink the power wire that enters the engine bay and joins together with the upper and lower engine harness.

4th relocated my s-afc with the extended ash tray thing that I found at the junk yard.

So after all was done I decided to crank her up. Noticed that the throttle and afm wasnt reading anything. Both read 0. So I started to jiggle a few wired and nothing.

went over to the throttle body and unpluged it and the car dies. Normally the revs increase a lil bit but not cut off. Then I went over to the maf and unpluged it. Nothing happened. Now during this whole thing I noticed a lil smoke coming out the tail pipe(just a little bit) So I placed a rag over the maf sensor and nothing changed. I know there is something wrong here but then again why is the maf and throttle not reading on the safc???

When I peg the throttle the engine does like a delayed 2 step and the turbo builds boost. I guess somehow the timing is retarding causing this effect.

Does anyone have any ideas?? I drove the car for the past 3-4 months with no problems. I mean everything I did this afternoon was minor stuff. Any advice would be greatly appreciated.

Mods:

-1989 240sx

-rb25det

-safc

-boost controller 12psi

-3 inch exhaust with cat delete

-freddy intake manifold

-q45 throttle body

-fmic with RFL bov

-aftermarket radiator with slim fans (2 fans)

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ok here we go. Today it was nice so I decided to work on my car.

1st I wanted to diagnose why my horn wasnt working. Ends up being that the relay is bad.

2nd I wanted to bondo my fenders. Thought that I didnt have any hardner so I skipped that task(later found the hardner)

3rd Heat shrink the power wire that enters the engine bay and joins together with the upper and lower engine harness.

4th relocated my s-afc with the extended ash tray thing that I found at the junk yard.

So after all was done I decided to crank her up. Noticed that the throttle and afm wasnt reading anything. Both read 0. So I started to jiggle a few wired and nothing.

went over to the throttle body and unpluged it and the car dies. Normally the revs increase a lil bit but not cut off. Then I went over to the maf and unpluged it. Nothing happened. Now during this whole thing I noticed a lil smoke coming out the tail pipe(just a little bit) So I placed a rag over the maf sensor and nothing changed. I know there is something wrong here but then again why is the maf and throttle not reading on the safc???

When I peg the throttle the engine does like a delayed 2 step and the turbo builds boost. I guess somehow the timing is retarding causing this effect.

Does anyone have any ideas?? I drove the car for the past 3-4 months with no problems. I mean everything I did this afternoon was minor stuff. Any advice would be greatly appreciated.

Mods:

-1989 240sx

-rb25det

-safc

-boost controller 12psi

-3 inch exhaust with cat delete

-freddy intake manifold

-q45 throttle body

-fmic with RFL bov

-aftermarket radiator with slim fans (2 fans)

What about limp mode?? I noticed anouther cat on NICOclub had the same issue. Never told what it was or if he fixed it but it is the doing the exact thing. Would this happen if im throwing a code?? Im sure that I wired the check engine light into the cluster but not really sure how to check codes.

It will have something to do with the AFM wire that you have to use for the SAFC. Probably a dry solder join or it's come loose.

EDIT: Or you changed the settings on the SAFC accidentally where you have to program what type of AFM you are using.

Edited by PM-R33
What about limp mode?? I noticed anouther cat on NICOclub had the same issue. Never told what it was or if he fixed it but it is the doing the exact thing. Would this happen if im throwing a code?? Im sure that I wired the check engine light into the cluster but not really sure how to check codes.

Nah. All my settings on the safc where the same after reconnecting the battry. The power wire,blk and brn wires broke off but I soldered those back. Everything is still the same.

I pulled code 12(MAf) once. Could not get it to pop up again.

I als code code 55. I read here

http://www.northwestnissans.com/board/showthread.php?t=26965

that this means all ok. When I get home today I guess ill check over all wiring with the maf,tb, and safc

found the problem....

comes to find out that when I went to relocate my safc that I pulled just a lil to hard. At the end of the wires is a plug. Well the plug goes inside the safc and plugs into some computer board inside the afc. I had to seperate it in order to plug it back in. Plus my plugs where fouled out from the none maf voltage. cleaned plugs and reinstalled. All good.

Oh yeah. I noticed that everyone says that the rb25's run rich. Well I have huge throttle body and freddy intake so I subtracted 2% from 5500 rpms to 7 grand. She pulled like a champ

found the problem....

comes to find out that when I went to relocate my safc that I pulled just a lil to hard. At the end of the wires is a plug. Well the plug goes inside the safc and plugs into some computer board inside the afc. I had to seperate it in order to plug it back in. Plus my plugs where fouled out from the none maf voltage. cleaned plugs and reinstalled. All good.

Oh yeah. I noticed that everyone says that the rb25's run rich. Well I have huge throttle body and freddy intake so I subtracted 2% from 5500 rpms to 7 grand. She pulled like a champ

And you pulled the 2% without putting a wide band on it? f**king smart...

Get it on a dyno NOW and check the AFRs.

Not "every" RB25 runs rich. Some have minor issues and make them run lean, although they seem to run perfect. Just guess working is bad

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