rolfs_7

Messed with tps lag and now it idles great! No tpsaccel coming on at all. Only problem is lag factor is at 12, fuel ve in the idle bin is 90.... idles fantastic though but probably won't drive for anything

rolfs_7

Tpsaccel not coming on at idle I mean

Aaron Cake

iTrader: (1)

With that much jitter, you need to fix your underlying electrical problem.

Also, lag isn't necessarily the best adjustment for this. The accel pump has a delta-TPS adjustment which defines when it starts to trigger.

rolfs_7

I know, I've done almost everything I can think of aside from a new alternator. Any more suggestions on how to get this noise out, grounds are ALL good, any specific size capacitor between the ground and signal that would be best? Ill try adjusting the delta-TPS and see what happens. Thanks Aaron.

NativeBeggars

iTrader: (1)

Can someone post a link to that ultimate regrounding thread? It seems relevant here,and I have been searching for hours with no result.

rolfs_7

Only one I remember is Aarons site. The chassis is completely regrounded, New powers new grounds everywhere. http://www.aaroncake.net/rx-7/grounding.htm

Black13B

iTrader: (1)

NativeBeggars, If you are unsure of how good your grounds are, take a set of booster cables and clamp engine block and chassis one side, and battery negative x2 on the other side. I've used this a number of times on FC RX7s to diagnose bad idling on OEM ECUs. Usually every car I dealt with needed a new ground going to the leading coilpack body ground. Some cars barely ran without having a new 4 gauge wire going to the coil mount.

rolfs_7, what kind of voltage are you seeing at idle now? 12.4 is minimum "charging" voltage. You should see around 13 to 13.5 volts.

NativeBeggars

iTrader: (1)

Thanks Rolf. I totally forgot Aaron had a great grounding page.
Black, thanks for the info. I'll give it a shot for sure. I'm not having any idling issues or anything. Car runs fine. I just want to make the reat of my interior lights work.

rolfs_7

Woke up today and logged my 20minute drive to work voltage is a lot more steady than it used to be, my stock gauge in the car used to fluctuate pretty bad until I rewired the alternator. Now that I look at it in megasquirt it drops way lower that it ever should at idle especially for nothing load inductive kicking on. I'll swap my alternator tonight and post results. It doesn't seem like I'm getting noise in any of the other sensors though that's what I found weird. Thanks guys

Black13B

iTrader: (1)

Interesting.

I have seen Cummins ECMs refuse to start an engine during cranking. Voltage dropping is normal during crank load, but turns out the Cummins ECM will not fire injectors with under 10 volts.

It can be confusing, since it will crank over just fine, but will not fire at all.

rolfs_7

Put a cap in and it helped some but not completely, I may have to isolate the tps portion of the harness. Anyone think it could possibly be noise in the MS?