How to burn through gas with a MSII!!!

[Shades]

So first thing is insert a faulty coolant sensor... one of the leads into the sensor was broken but still made contact once in a while. What this did was put the car in warm up mode and off warm up mode... so in turn this dump fuel and then goes back to normal.

Second thing is run old code... if you're running a wideband it makes your AF's go all over the place. This makes the car dump fuel and cut fuel back and forth, back and forth... not fun.

Third and new thing for me this week is while cruising... that is on the highway with your foot at one position on the pedal and not moving. You watch the accel enrichments kick in and watch the decel cut kick in right after. What this does is dump a bunch of fuel and you loose a wack of power, and then when the decel cut kicks in the car bucks a bit. I drove 100km's today and burnt up half a tank of fuel.

I have yet to find out what the problem is... let you know when I do, so if anyone else has this hopefully this will help them.

So much money has been spent on gas trying to break in my new engine also... and I don't think that these big fuel dumps are good for the engine either, but it's better than having it lean out.

[Lex]

Hey Jon, I will post the reply I sent you to your e-mail here for anyone that may have the issue. This is to resolve the last issue, hitting accel enrichment randomly:

"Just briefly went through the logs and you are activating the accel enrich because it is probably seeing noise on the TPS line. It seems to see a TPSDot (rate of change of TPS) of 5.1 and activate the enrichment. You can set the threshold in the Accel Wizard menu under Tuning and the parameter is called TPSDot Threshold. Set it to something like 6.0 and see if you get the spikes anymore. It should resolve the problem."

[therieldeal]

yeah just increase the accell enrichment threshold for whatever type you are using... TPSdot or MAPdot

[Shades]

Yup, I upped the TPSdot... it seemed to fix that problem.

The new one is that on accel it'll go lean (16's) then go rich like it should... then on decel it'll go rich (10's) then go back to stoic like it should. I've never noticed this before... normal, yes/no?

I'm thinking this weather is making things go all funny.

[Lex]

Maybe you added too much of a threshold. The threshold should be low enough so that you register the change in TPS and high enough so you don't falsely trigger it. Play around with it until the car has a nice crisp response to accel. It should not go lean if you completely stomp on it quickly.

On decel, you are not removing any fuel last I remember the tune (it is at 100&#37, so it is normal to kick slightly rich and go back to normal. Having decel at 100% makes shifts smoother I noticed.

[FE3-323]

sounds like me when i had a hole not firing off 70% of the time..

[therieldeal]

the lean/rich spikes are normal like alex said... i have my decel fuel cut on 90% and it seems to reduce that rich spike a little and still shift smoothly. as for the lean spike you may need to tune your accel enrichments a little more. but a short lean spike wont hurt anything, just tune it so the car doesnt stumble when you stab the throttle.

[Shades]

Ok kewl... fixed most of the problems with help from Lex...

I'm trying to turn for start-ups and I know you only get one chance until it totally cools down and you try again.

So I'm wondering what Priming Pulse and what Cranking Pulse numbers do you have for your start ups? Say for instance if you were to make the graph using the linear function, what do you insert for -40 and 160?

Right now I've set it to 8.7 @ -40 and 2.0 @ 160. When warm it fires up first turn key... on cold start up, it takes about 2-3 tries (3 seconds each try, don't wanna burn out my starter).

[therieldeal]

what size injectors do you have?

and your priming pulse you can set the whole table to something small like .5 or less ... thats mostly for TBI.

[Lex]

Try a little bit richer on the cold start and see if it helps Jon. I noticed a little more fuel really helps when it's cold.

[Shades]

I'll try a little richer... I have stock injectors, what are they 240cc?

[FE3-323]

256cc

[svtfast]

DAMN I just noticed this thread but 5-6 gallons for 62 miles? Sounds like my 1.9 Escort at 4400rpm but I got just over 100 miles with 5-6 gallons.

[Shades]

Well, my engine is tuned decently...

But I am still burning through a lot of gas... I guess it's cause I'm running a GTR intake manifold with short runners and I'm only giving it 15-25% throttle and it's reading the MAP values for WOT, 100kpa.

This tank around I got about 250km's... I'm hoping when I go turbo that it will get better.

Fixed my cranking issue, someone changed the cranking to 250rpm's cut rather than 300rpm's, cause I checked the rpm's when cranking and it's cranking at around 260rpm's... so the starting cranking and priming pulses did not apply.

[Lex]

So does it start much easier now?

Well, my engine is tuned decently...

But I am still burning through a lot of gas... I guess it's cause I'm running a GTR intake manifold with short runners and I'm only giving it 15-25% throttle and it's reading the MAP values for WOT, 100kpa.

This tank around I got about 250km's... I'm hoping when I go turbo that it will get better.

Fixed my cranking issue, someone changed the cranking to 250rpm's cut rather than 300rpm's, cause I checked the rpm's when cranking and it's cranking at around 260rpm's... so the starting cranking and priming pulses did not apply.