datsun280zxt

when i start running the car on 1st gear at 5000 rpm it creates backfire, i checked the fuel injections they're fine.. i have a 1981 280zx turbo with a t5 swap from auto to std. i have a 3 inch pipe strait with a skunk2 muffler, any suggestions of what could it be.. thanks

NismoPick

It's probably running too lean. Check your a/f ratio.

datsun280zxt

i was thinking probably it could be the regulator cause the maf i replaced it like a yr ago.. but thanks i will check that

WildmaN

Sometimes you have to set the AFM, or MAF to the engine it is in. I bought a brand new AFM for my '82 N/A. And it didn't run right. I still had to screw around with the A/F mixture. When you pop off the black cover. Just barely push the mechanism that moves up and down. If it starts to bog, when you barely push it down. You should be at the right A/F ratio mixture. If it doesn't bog down. Hold the wheel with the teeth on it. And loosen the phillips screw. Be careful, and don't let the wheel slip. Or you will have to rewind it. And that will be a pain in the butt. Also, make sure you mark it with a sharpie. Where it is set at. In case you need to put it back in that place. Anyway, as soon as you get it where you want it. Mark the new position on the tooth. After tightening the screw that holds the wheel in place. I don't know how much different a turbo is from an n/a. But I would imagine they are almost the same inside.

Another thing you can do. Is check your TPS. When you hold the throttle lever at a steady spot. If the engine runs an erradic idle. You are too lean. So barely move it counter clockwise (to the left) Until it runs even on a steady throttle. Then tighten the screws while holding the TPS in the right spot.

Now these tips are from adjusting an n/a. I don't know how much different they are from a turbo. But hopefully it helps. Good luck.

datsun280zxt

thanks i just changes the timing chain and found out that is it was the pickup coil that was bad so i change the distributor from an 82 turbo and it fixed the problem with the back fire, know i need to check like u said the MAF due to is not putting enough gas to pick up the 6 1/2 rpm.. it only goes to 5 1/2