Alright I have my maps Fuel And Ignition pretty much nailed for easy driving when the car is at opperating temp the engine has been broken in for about 1000 miles or so now. and she starts and iddles just fine without BAC assistance. Also the weather has been getting nicer and it has been harder and harder to tune for cold start and driving. However.
when I start my car my wide band says it is iddling at 14.6-15.9 which doesn't seem right, but the Narrow band o2 as well is pinned at lean. I am simply wondering what would make the car stuble (because it is going soo lean), I have tried Making the the coolant temp richer and richer but still to no avail... I tried making the air temp maps a little richer but then my ENTIRE map is rich... so I returned the map to it's original fine tune. So does anybody have any other suggestions, once the car is up to operating temp again it works just fine. I have played with almost every correction map... and none have really helped out.
Thanks

 

Does the stumbling happen @ idle during warmup or only when moving the throttle / during transients?

You may have to increase your coolant factor for the throttle pumps if it's only when you push on the gas.

 

I still think that's not enough miles for the motor to be properly broken in.
What are you idle vacuum values now?
Keep note of them and see how much they change over the next 3 - 6 months.


-Ted

 

it happens during transients, and when moving the thottle.

 

Alright I ramped up my correction maps for coolant-fuel and I am still getting the exact same stumbling, my WB02 Afr's go full lean, and the car hit's a brick wall it seems, and EGT's fall off to below 300 deg C (lowest Reading on gauge). Could this be timming corrected.
Because in the coolant-fuel correction it is about 60% at 40 deg C... which to me should be REALLY RICH... anybody have any thoughts?
Thanks Again.

The engine has 4000 miles on it since rebuild, I think that is plenty to start pushing more than 4 or 5 psi.

As for idle vacume values they are about -60 70 kpa. that is alot better than what I have before which was really crappy my BAC valve was going all the time to keep it iddling, now it barely comes on.

 

Try increasing the coolant factor in the throttle pump page if the stumbling occurs when you push the throttle and not @ steady states. What is it currently set to?

 

Here is a screen Shot, I am not entirely sure about this, I have done as much reading as I could... but can't find alot of info on this... so please educate me...
Thanks alot guy's after all the fighting it took to get this thing running, and figuring out all the little hook-up's are really putting me below the learning curve... but it will all be worth it in the end...

 

Increase the coolant factor, mines currently at 2.6, you should be able to get away with less if you are using the original intake manifolds and throttle. Try 1.0 but keep increasing it until the stumbling is gone when cold, this only comes into play when you are pushing the gas pedal. After the car is @ operating temperature the coolant factor is not applied (once the coolant temp correction is @ 0 because the engine has warmed up).


If you get stumbling during throttle changes @ operating temperature you may need to increase the throttle pump values also, but if the problem is only when cold change the coolant factor and the coolant temp correction maps.

 

well the cooland temp correction maps are SUPER Rich... right now at 40 deg C it is like 60% and then down from there.
But I will hook up my laptop tomorrow and fiddle with the throttle pump settings and see how it goes.
Thanks again pengarufoo.

 

I'm having the same problem. Any help is welcomed!

 

alright, the problem was gone while the weather was warm... but now it is cold again. I have my throttle pump set at 2.1
and my coolant correction maps are rich.
Now when I hit it... it is like hitting a Brick wall.. the car falls flat on it face, and then if I keep the throttle held in the car backfires. and the WBO2 gauge reads FULL LEAN. Anybody have any other suggestions, thus far you have been extremely helpfull.

 

Check air temp map?


-Ted

 

air temp fuel map? If so here it is;
does it need to be more steep? I mean 10 Deg C isn't all that rare what do you guy's have arround that area?

 

ok a made my air temp maps about 10% more rich... and the stumble is still there and still hits like a brick wall.