L-Jet going full Rich on Deceleration Options

[Brian Fuerbach]

1974 1.8 with L- jet. Been playing with a wide band air fuel meter and noticed that when I lift the throttle the AFR goes to max value on the gauge. I thought it was supposed to go lean. I checked the throttle position switch and it checks out fine. Going to check the wiring harness next.

What else should I check? Decel valve?

[wonkipop]

@Brian Fuerbach
that description above about L jet really having no way to adjust for how much fuel its actually putting in provoked the next inprovement. closed loop systems with 02 sensors at the end of the track. at least then it could adjust itself on the fly and compensate for another part of the system that might be screwing up slightly.

thanks to your question i know that the harmless looking fuel pressure regulator is doing an important job with its vacuum section in the L jet cars. all the electronic injection german hokum pokem, then its got a cuckoo clock vacuum unit controlling half the hand cuffs on the amount of fuel coming out of the injector.

in a funny way you have given yourself a closed loop system?
you know too much about what its doing but there is no capacity to adjust itself on the fly.

i am sort of glad i don't know whats going on when i lift off the gas. (IMG:style_emoticons/default/smile.gif)
probably worse than yours.


what you said about getting to the bottom of the hills and having a rough idle -
sounds like its dumping a bit of gas in its not able to burn and fouling the plugs a bit?

[Brian Fuerbach]

@Brian Fuerbach
that description above about L jet really having no way to adjust for how much fuel its actually putting in provoked the next inprovement. closed loop systems with 02 sensors at the end of the track. at least then it could adjust itself on the fly and compensate for another part of the system that might be screwing up slightly.

thanks to your question i know that the harmless looking fuel pressure regulator is doing an important job with its vacuum section in the L jet cars. all the electronic injection german hokum pokem, then its got a cuckoo clock vacuum unit controlling half the hand cuffs on the amount of fuel coming out of the injector.

in a funny way you have given yourself a closed loop system?
you know too much about what its doing but there is no capacity to adjust itself on the fly.

i am sort of glad i don't know whats going on when i lift off the gas. (IMG:style_emoticons/default/smile.gif)
probably worse than yours.


what you said about getting to the bottom of the hills and having a rough idle -
sounds like its dumping a bit of gas in its not able to burn and fouling the plugs a bit?

I am always looking for something to fix even if doesnt need it. I started using the wideband meter because I bought a rebuilt AFM from Fuel Injection Corp. and it was setup pig rich when initially delivered. The clock wheel was a half turn off. I have my AFR's pretty dialed now and all the other l-jet systems are functioning properly. I just wanted to get the decel afr's in line but sounds like that is just the way it operates.

This is what led me to think the TPS was malfunctioning. Just so I am clear, the only two pins used on the TPS are #18 and 3 which are input and WOT. The TPS switch is open between 18 and 3 at idle and closed just after tip in all the way to WOT. This is how mine is behaving.