S130 running real rich

[akumazedex]

After hours of trying to figure this out I'm completely stumped. Here's the problem. When the car is cold, start it up and it'll idle and run just fine. As soon as it warms up te idle drops real low, begins to run really rich. Looses power until fuel is cleared out at the high rpm 4k+. Also vacuum drops from 18 to 14, and I'm almost in boost cruising at 75mph.

 

Here's some background on the car. '82 280zx stock L28e converted to turbo, running N/A ecu, harness dizzy etc. never have me any problems until about a week ago.

 

What I've checked.

 

Afm - good ground, ~5v idle (set idle a bit high)

CHTS - ~2v fully warmed up.

No fuel in pressure regulator and runs even more rich when unplugged.

 

What it has new

O2s

Injector connectors

Spark plugs

Alternator

 

I've also tried swapping out CHTS,AFM and ECU's with no difference.

 

So now I'm stumped, any ideas or advice would be amazing!

[akumazedex]

So I just went thru the entire efi yesterday and everything that is hooked up is working as it should. Just did an alternator test on the new alternator I put in and it failed at 12.45v and 5 amps with all the accessories on (lights fan etc) having the parts store order two and testing them there. Hopefully one is good. My fault for not having them test it before I put it in. So my original assumption of my alternator being bad was correct. Low charging voltage and low amp output will cause problems with the computer reading the correct signals. Hopefully this will take care of it.

[NewZed]

After hours of trying to figure this out

 

 

'82 280zx stock L28e converted to turbo, running N/A ecu, harness dizzy etc. never have me any problems until about a week ago.

 

 

What I've checked.

 

Afm - good ground, ~5v idle (set idle a bit high)

CHTS - ~2v fully warmed up.

 

 

What it has new

O2s

Injector connectors

Spark plugs

Alternator

 

I've also tried swapping out CHTS,AFM and ECU's with no difference.

 

 

Most people spend days, months or years trying to figure their engine problems out. You are outside the lines with the turbo on the NA EFI system which may be why you didn't get much feedback. It's the "asking for trouble, you're on your own" path. Plus reporting voltages for the AFM and CTS test doesn't really mean anything since the tests describe measuring resistance.

 

I'm not a turbo guy but the fact that you're boosting early seems to suggest a problem with the turbo and boost control (of course)(Edit - had written something else but it was backward thinking). Reporting RPM instead of MPH would probably be more useful too.

Edited October 22, 2012 by NewZed

[akumazedex]

I know I'm going an unorthodox route with my motor, but it's proven that it'll work just fine. I had this set up for probably a year now with no problems. Like I said in The earlier post, I went through the whole efi and tested the resistance values as per the fsm. Everything I found was right in the middle of the min/max resistance values the fsm gives you. I did find that my tps was out of adjustment and that my afm had a bad temp sensor. All that has been sorted out. My only thought would be the alternator that tested bad. I'll put that in today and see how it goes.

[akumazedex]

So with a new alternator I'm still having the same problem. I actually found out that its only when I put a load on the alternator that it stops charging. I did a bit of digging yesterday and found my black (acc) fuse link was corroded pretty bad. Replaced that and still no change. From what I gathered that fuse link is what brings voltage to the alternator + and the energize wire (white). I'm gonna go thru the charging circuits later and see if I have any problems there.