Well when I was driving back to school yesterday (took 6 hours), I stopped and got some gas. Then hit traffic inched forward for maybe 30 minutes. And then after we got going again, I noticed that in vacuum between like 5"-18" about, the car would bog down for just a second then go normal then bog down again. The zeitronix showed it going way rich (10:1 or 9:1) when this happened. Car runs fine in boost and in vacuum greater than 20"hg. So either the megasquirt is deciding to add fuel for some reason in that area, maybe the map sensor is seeing less vacuum than is there, I'll have to take a log but my laptop battery is crapping out on me. Or maybe theres something wrong with the ignition, but then I would think it would happen under boost as well. Any other ideas?

Are you talking about while you are lightly cruising with steady pressure on the gas pedal? If its that, it could be your EGO settings.

Honestly i think its in your map. 18" is down at the bottom of the VE table. the very bottom bins are probably rich because you hardly ever use them. Look at your logs to see what bins you were drawing drom and check the ve number that was being added to confirm. Then adjust as necassary.

Terry

The map looks good nice and uniform. The weird thing is I didn't change any settings from before and it was running just great. Then when I stopped and got gas, got back in started driving and it started happenning. K here's a screen shot of the datalog. You can see on the top graph the afr fluctuating.

did it stabilize after it ran for a while? could have been heatsoak from sitting at the gas station for 5 mins. I have never had it go rich and i really cant use the garph much since i cant scroll around to compare map values, ego corr value, and temp.

Nah it didn't get any better, that log was from a couple hours ago. I can send you my msq if you want to browse through it.

sure, cant hurt. send me the Log as well.

After it cools down its no better? So it keeps doing this? Any changes in the weather? Different gas? Wait after you filled up it started.......thats interesting.

Send the logs/msq anyway, also send me a log from the day before. I want to see how you are tuning. In the mean time burn through that tank quickly. Lets rule out a possible gas issue.

Terry

Originally posted by Star Turbo Talon
sure, cant hurt. send me the Log as well. After it cools down its no better? So it keeps doing this? Any changes in the weather? Different gas? Wait after you filled up it started.......thats interesting. Send the logs/msq anyway, also send me a log from the day before. I want to see how you are tuning. In the mean time burn through that tank quickly. Lets rule out a possible gas issue. Terry

Alright sent the logs and the MSQ file. And no after it cools down it's not any better, it's the same hot or cold, weather doesn't matter. Yea I was a little curious that it started after I filled up as well, maybe I got a bad tank, oh well I didn't fill it all the way up so it shouldn't take long to go through. Oh and the MSQ is on the 029t firmware. Thanks a bunch.

No idea who you sent it to. my email is terrence.godfrey@sbcglobal.net

Terry

Wierd that's where I sent it, oh well I just sent it again. Did you get it?

Well I got a new tank of gas, gone about 70 miles on it so far, and it's still there. Now the idle is getting rich and jumping around a lot. It'll rev itself up and down from like 500-2000rpms sometimes. I feel like a ricer whenever I'm at a stoplight because people keep looking at me thinking I'm trying to race. Sometimes it will idle fine, and other times it'll be really lumpy and rich. I'm very confused.

Alright well just so you guys know I figured out what it was. The acceleration enrichment was going whack because of something with the tps signal. I haven't had a chance to examine it further, I'm hoping it's just a lose wire or something, or maybe the sensor is going bad I don't know. Anyways I just switched it over to map sensor based acceleration enrichment and it got a lot better, don't have the settings quite right for it yet but definitely better. Can someone tell me what they used for the map accel enrich values. Like the threshold and stuff, I would appreciate it.

What was your TPS threshold value? I have mine in the 1.5-1.6v/s range to keep the noise induced, false triggers at bay..

I think the TPS one was like 1.172V if I remember correctly.

Originally posted by BlackMagic
I think the TPS one was like 1.172V if I remember correctly.

Try raising the value somewhat..Try 1.5v/s or around there, and then open up the "tuning"- "realtime display", and watch the TPS if it blips at all. It should not move. If it still twitches a bit, increase the value in small steps until it stops. I've played around with map accel, but i never had good luck with it, although i didnt spend much time with it either.

Alright cool I'll give it a shot. I wonder why it just randomly started to do this though. Oh well if it works it works.