Supra Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
9,670 Posts
Discussion Starter #1
Does this problem still exist after the fuel system is replaced? I am planning on upgrading, and I need to know if I can go back to an OBD1 setup...I really hate the CEL frequency+no trac of the OBD2.

Jason
 

·
Registered
Joined
·
6,785 Posts
Jason, IIRC while i was searching for this topic a while back. The lean spot is still there, but most singles spool hard right after the rpm's where the lean spot is. I am going by memory though, so dnt hold me to that. Not sure what the smaller singled cars do if they have obd1
 

·
'95 TT
Joined
·
668 Posts
The problem with the OBDI lean spot is that OBDI ECU does not increase the injector duty cycle enough to compensate for increased air flow for those RPMs. I would imagine that if you replace your fuel system with something with more flow, like larger injectors that the duty cycle during that lean spot may now be high enough to keep it from going lean.
let's say the duty cycle during that lean spot maxes out at 70%

70% on a 550cc injector may create a lean spot, whereas 70% on a 800cc injector may provide enough fuel.

With that said, it also depends on your turbo size. It's likely with a decent size single that you'll hit max boost AFTER the rpm range where that lean occurs.

All in all, the problem will still be there just more hidden than before.
 
1 - 3 of 3 Posts
Top