constant speed surge

Pagemo · Post by **Pagemo** » Wed Jul 26, 2006 12:34 pm

MS2 V3 Turbo 2.6L 4 running edis
I am having problems with a surging at constant throttle. It does not matter what RPM if you hold the throttle constant for a little while the car will eventually start a light surging. If you get on the throttle at all even very little it pulls nice and smooth. The AFR is not ranging far enough for lean conditions.. at I don't think it is I have not had a good data log yet. What else would cause this?

mops · Post by **mops** » Wed Jul 26, 2006 1:43 pm

check your ego correctiong. If ego authority is more than 5% in come cases it can cause surging (basically ego correctiong osciallates between min and max all the time). Best way to disable it and check whether that fixes the problem. Depending on the timing you are running, 16:1 afr's can cause surging... with advanced timing you whould be able to run 17:1afr's

Pagemo · Post by **Pagemo** » Thu Jul 27, 2006 4:58 am

Thanks, I checked that last night and a few other things, I ran a datalog I am pretty sure now that the problem is noise on all of my signals CLT,IAT but mostly TPS causing AE to kick in, While driving it I noticed the LED on the MS lighting almost perfectly in time with the surging.
So I looked at the datalog and all of my signals have what looks to be a good bit of noise, I changed the grounds for my EDIS to another place on the block, I have the MS and IAT, CLT grounded to a different spot on the block and tried moving my +12 wire directly to the battery just to see if it helped..No change

What should I be looking for to reduce noise across the board? Does EDIS require the dave cap or C30?

One other question I noticed when I hooked up the MS directly to the battery the injectors are making a clicking noise? I thought the injectors were fired from ground through the MS why would they energize when the MS is powered up?
The car runs pretty well other than this.
I can upload a datalog file but i need a host?

Scott

mops · Post by **mops** » Thu Jul 27, 2006 12:36 pm

injectors get constant +12v, and ecu grounds them. they should be always ticking when working..

the way to fix grounding issues is to connect ms with all sensors, including lc-1 (if you have one) to one common ground, and the run a wire from that point to battery negative.

noise on all sensors can be caused by flustuating battery voltage. if your alternator is on it's way out it can fluctuate hance all the sensors do wierd things

to fix unwanted accel enrich incerase AE treshold and that will fix your problem for now

Pagemo · Post by **Pagemo** » Fri Jul 28, 2006 5:04 am

Thanks for all of the info Mops!
As of last night I had some real improvement, I rewired all of my sensor grounds to pin 19 on the MS, Ran the other MS grounds directly to the block, and moved the EDIS ground to another point on the block. This cleared up all of the problems with AE kicking in. also moved the LC-1 analog grounds to the block with theMS. Datalog now looks really clean

I know this is more in the lines of wiring and sensors so I will move my other questions to that board.
Thanks again!
Scott