Super rich running on my 86
07-30-2010, 12:10 PM
#16
Racer
Thread Starter
I checked to see if the element in the maf glows when the ignition is on and it doesnt glow.
I then tested to see if the car ran differently with the maf unplugged andwhen I started it without the maf the idle didnt search from 200-1500 rpm like it used to and the smoking went away. What it did do was search from 800-850rpm, which it has never done, but other than that it didn't seem to be all that upset.
I set the maf back to 580ish ohms and plugged it in, like it was before I put the car under the knife, and it started the same but died 2 seconds later. I tried again and it started fine and almost died but recovered and reved to 2k rpm and then fell back down and up and down and died.... unsure of level of fumes it didnt run long enough.
......?
I then tested to see if the car ran differently with the maf unplugged andwhen I started it without the maf the idle didnt search from 200-1500 rpm like it used to and the smoking went away. What it did do was search from 800-850rpm, which it has never done, but other than that it didn't seem to be all that upset.
I set the maf back to 580ish ohms and plugged it in, like it was before I put the car under the knife, and it started the same but died 2 seconds later. I tried again and it started fine and almost died but recovered and reved to 2k rpm and then fell back down and up and down and died.... unsure of level of fumes it didnt run long enough.
......?
07-30-2010, 12:12 PM
#17
Captain Obvious
Super User
Super User
If the above is true the how come, when I had one injector disconnected, it passed the emision test with flying colours? I also idled fine but was down on power and felt a bit unballanced under load.
07-30-2010, 12:56 PM
#18
Rennlist Member
Wrong assumption - the MAF wire glows for a couple of seconds after the ignition is shut off (to burn off any accumulated deposits), not while it is running. Also, the burn-off is so fast that you cannot see it if you are working alone. You would need to watch the MAF wires while someone shut down the engine. And observing the burn-off cycle is no indicator that the MAF is in spec/calibration.
07-30-2010, 01:10 PM
#19
Nordschleife Master
Gaz,
reread John Speake's post.
Chris,
I would try finding another MAF to swap for giggles.
Imre,
I have dont that in the past to pass emissions with some vehicles. You need to disconnect the O2 for it to work. Or have a dead one already in there.
reread John Speake's post.
Chris,
I would try finding another MAF to swap for giggles.
Imre,
I have dont that in the past to pass emissions with some vehicles. You need to disconnect the O2 for it to work. Or have a dead one already in there.
07-30-2010, 01:10 PM
#20
Racer
Thread Starter
I was following john Speake's suggestion that if it DOES glow then there is a problem. The point was that it didn't glow and that was good.
I was more concerned with the two paragraphs that followed that. Any clues as to what that means?
I was more concerned with the two paragraphs that followed that. Any clues as to what that means?
07-30-2010, 01:20 PM
#21
Rennlist Member
Your tests seem to confirm that the rich running isn't due to leaky injectors.....
Maybe an O2 sensor problem ? Try unplugging the O2 sensor, the LH ECU will revert to mid range of the loop, the car should then run pretty well if the O2sensor is the problem.
Maybe an O2 sensor problem ? Try unplugging the O2 sensor, the LH ECU will revert to mid range of the loop, the car should then run pretty well if the O2sensor is the problem.
07-30-2010, 01:33 PM
#23
Inventor
Rennlist Member
Rennlist Member
Has anyone mentioned Temp II, yet?
If disconnected or bad, it will run rich.
If disconnected or bad, it will run rich.
07-30-2010, 02:35 PM
#25
Rennlist Member
MAF may still be the problem. Try to measure MAFoutput volts while engine running at idle. Should be about 2.7v. If much higher, then that is the problem.
Pin 5 on MAF, pin 7 on LH ECU.
Pin 5 on MAF, pin 7 on LH ECU.
07-30-2010, 02:39 PM
#26
Racer
Thread Starter
so measure voltage at the 7 pin on the LH connecting the other lead to ground? There is no way to test at the maf directly when running so I assume this is what you mean...?
07-30-2010, 02:44 PM
#27
Rennlist Member
07-30-2010, 02:46 PM
#29
Rennlist Member