ok so i was driving my 1983 280zx turbo and downshifted to speed up... and then all of a sudden sounded like tons of backfiring and stuff. i see the pressure relief valve next to the EGR is popping and backfiring out of airbox i think? i can get it started by pumping the gas.... then by hitting the accelerator i get the pop off valve going off and backfiring.

when i drive it i have nooooo power hardly when i hit the gas just popping noise's but when i hit the throttle slow it speeds up. OH and when i downshift no popping just rpms rev with no problems, so engine is fine thank goodness lol.


so i wonder what i screwed up. plz help

 

Have you tried doing a boost leak test?

 

how do i perform that?

 

How do you see this? Are you driving w/ no hood, or are you revving it in park w/ the hood up?

 

im reving it with my hand in nuetral, and listening to the engine...

 

So it's backfiring out the intake, which means it's running lean. I suggest checking your CHTS & AFM & connections. Also, I suggest pulling your spark plugs & reading the tips to see if one cylinder isn't firing.

 

ok i will do this tonight and check back.. Thanks

 

I'm not sure if I want to know how you got your hand in neutral...

 

me either

Well i looked at the car and i cant find it out, i think im gonna have to sink in and go to a mechanic

 

any more ideas before i take it in monday? i got fuel and compression is there.. so an air issue im assuming. sparks is there too. i just am stumped lol. Very hard to start it now.

 

A small rubber hose may have come loose. Your air flow meter could be bad.
I do not think it is the POV on the intake manifold. That thing flutters when it releases air.

 

Did you double check your timing? The distributor could have moved...

 

Is the parking brake on?

 

I took it to the mechanic the other day, dont know what was up, but im thinking its a valve bent or stuck. Well see what he says

 

When was the last time you replaced the fuel filter?

 

just recently like a week or two before. i checked it aswell

 

I got a call from the mechanic today, it was a rocker that fell off

Didn't break anything, still had that rough idle, so there looking into that as well, might have them fix it all up while its in the shop.

 

ok i was driving and my rocker fell off (playing to hard)... anyways i took the valve cover off and one of the rockers in the middle was sitting off nothing bent just pushed off. soooo i was wondering how do i get that back on the cam guide. do i have to take off camshaft? or can i slip it on again?

ty in advance

 

Merged with your previous thread... in which you stated the shop found the rocker problem... so... did they fix it and it fell off again? Or is this the same problem?

Also, time to break open that HAYNES manual or FSM.

Click: https://www.zdriver.com/forums/240z-280zxt-s30-s130-tech-tips-275/aftermarket-cams-cam-removal-installation-pics-19939/

 

Thanks.. they fixed it and i drove it again till i played to hard and it came off again, but i wanna fix it myself not a 150 dollar bill. i just need to slip the rocker on the guide. so whats the easy way to do this. i got a new guide btw.

 

i can simply just push the valve down and slip it on?

 

Dude... did you look at the link I posted? Do you have a Haynes manual?

You can download the FSM from www.xenons130.com/reference and it has detailed steps on rocker R&R.