MS2 Setup Help

[dskopek]

I have some but it is not anything near a stock cam. If you want them let me know and I can ship them to you.

[Maverick H1L]

Things are going backwards... Seems like the more holes I plug, more parts I get (breather tube), more bolts I tighten, the worse the vacuum leak gets (currently around 70 kPa). Seems to me that the sucking noise is coming from the back of the engine, and the only thing back there that could be causing the issue is injector o-rings. Funny thing is that I didn't have this issue before I replaced the alternator and the alt bracket and had to deal with the CKP setup. Even after replacing the fuel injectors (which had good o-rings on them when installed).

I guess that first thing tomorrow, I'm going to take off the upper plenum (hoping that the plenum gaskets don't tear again or I'll have to go and buy another set) and lift the fuel rail to check the injector rings. Other than that, IDK where to go from there.

[Maverick H1L]

Well, I've found a couple of issues...
1. #3 and #5 injectors apparently don't like to go as far down into their bores as the other 4... I may have to bend the rear fuel rail bracket lower on that side at some point...
and 2. I'm wondering if anyone seems to have the issue I'm having with the valve cover not quite being aligned properly with the back of the intake (non-thermostat end)? It looks like that may be where the mystery vac leak is coming from. The top of the valve cover is down towards the head about 3/32 of an inch while the rest of the cover is aligned properly.

Yes, I'll take the ASE and WUE curves... It's still being a royal PITA to start, especially when hot. I'm going to go back into the TS and work on the crank PW at some point, but I need to get some more threaded inserts for the valve cover screws first, to make sure I get the driver's side cover as tight as is necessary once I finally get it aligned. I did go through yesterday and get the VE table done up, and I also removed about 5* of timing from 95% of the timing table. It runs pretty well, once I can get it going...

[Maverick H1L]

Well, I put the 5* of timing back into it, seems to like it better.

Put plates on her last week. Found out my cruise MAP band was lean so I added fuel to it down there. Ended up adjusting a couple of other things and the engine idles and what not fine, except at between 1500 and 2000 RPM. I'm going to try adding more fuel to try to get the setup to allow me to drop the idle speed and open the IAC some as it's completely closed right now (adding steps when hot does absolutely nothing).

I ended up pulling off the driver's side header the other day and resealing it to the head and to the pipe down below. Still need to get back under there and tighten the pipe connection. Ended up crossing plug wires around and scratching my head until I figured it out. Ended up adding 5 points to the entire VE table this morning only to find out that the WUE is messing everything up. Starting when COLD is much easier now, haven't tried hot yet due to the fact that I had to plug the laptop into the wall inside the house right when I got home.

ASE and WUE curves are too high, idle speed too high, jerky acceleration and driving. Unfortunately, I can't do any drive tuning at the moment because the DC adapter I have for the tuning laptop broke within a month of first use (seriously, the end that goes into the laptop power port pulled right out of the plug due to shoddy manufacturing), and the battery only lasts 10 minutes (if I'm lucky). I have ordered a new one of both off of eBay. I'll get a datalog and send out files once I get the battery and stuff.

[Maverick H1L]

Well, the battery should be here shortly, according to the tracking info, so I should be able to get something done at least.

I forgot to add above that the idle speed INCREASES as the engine warms up. When first starting, it starts around 1200 RPM and ends up at about 2000. I'd like to try to close the throttle plate completely and just use the IAC for minimum air control, but I already know the adjustment screw isn't going to turn (I have a spare TB and the head came off of the screw when I tried to turn it yesterday), so I'll have to figure something out.

[dskopek]

Try increasing your IAC counts once and make sure the idle goes up and not down, you could have the IAC coils wired backwards, it will still work but inverted. Been there,done that- I am running my thottle plates closed and am just using the IAC for idle control, works pretty good, need to have the fuel mix right at idle for it not to surge sometimes.

[Maverick H1L]

I know the IAC is wired right... When the counts are increased, the idle goes down TO A POINT, and the idle goes up when the counts are decreased. All of the wiring was checked several times before being installed.

Right now, I'm stuck with what I'm pretty sure is a fouled plug. I've had this issue before, before I did the hybrid swap, but I know the results... I'll take all of them out and clean them (and replace if needed) before I go back into TS. The battery for the laptop SHOULD have been here today but wasn't (I hope it didn't go to the house across town that we keep getting mail for), so I should have time to get the plug(s) sorted out.

[robertisaar]

MS works in the opposite direction of GM? with the GM ECMs, more steps/counts = more airflow.

[Guest]

MS works in the opposite direction of GM? with the GM ECMs, more steps/counts = more airflow.

This ^^

In GM control, a lower IAC count means that the pintel is more extended, which means there is less air flow. The pintle when fully extended seats into a hole that block airflow, and is when the pintle is at 0 steps (theoretically). Some IAC steppers have a max count of 160, which means fully retracted. Others are less steps, I want to say 120 steps is fully retracted.

[dskopek]

On my setup with MS 0 = less air and 170 is max count. On cold idle I run about 45 counts and 1300 rpm idle speed and hot is 10 counts and 900rpm.

[Guest]

On my setup with MS 0 = less air and 170 is max count. On cold idle I run about 45 counts and 1300 rpm idle speed and hot is 10 counts and 900rpm.

Looks to be the same as GM set it up then.

[Maverick H1L]

IDK why it works the way it does... I can get the IAC counts to a certain point before the idle starts going UP (and I'm talking 3000+ RPM). It will be at a certain # of counts one second, and if you add say, 10 counts, it jumps UP. Yes, it's confusing. I'm not sure what's going on. The idle speed was WAY high with the base IAC step settings, and I'm running at minimum around 150 counts (cold) and over 200 hot.

I haven't yet pulled the intake to basically put new gaskets and everything in and make sure it's sealed. Today I got a couple cans of starting fluid to check for the vacuum leak, sprayed all over the place, and found NOTHING. Not only that, I didn't hear anything either (normally sounds like a vacuum cleaner). So I went and hooked up the charcoal canister and it was fine. Until it warmed up. Which is when I shut it off to check the hot start PW, which was a mistake. Rough start, as usual (partially the starter's fault, but the extended crank isn't), won't idle without holding the throttle slightly open for a little bit before letting go, and the idle pressure was around 40 kPa (normally idling at about 32 at the moment). It takes FOREVER to almost settle to normal.

I'm going to try again tomorrow. I wish I had one of those evap system leak testers... I'll get busy tomorrow and get the intake taken care of before I get a datalog.

[Maverick H1L]

Well, today I tore the engine down and replaced the intake manifold gaskets. I used RTV on both ends of the engine from one head to the other on both entire ends of the engine. I also replaced the intake end injector o-rings. I haven't started the engine yet due to it getting dark by the time I got everything bolted back up. Right now, I'm just hoping that I set the valves properly and I won't have the pull the valve covers back off (and then fight with the driver's side spark plugs so I can get the compression gauge in).

After that, I'm going to go into the MSII software and reset the IAC counts... Going to need some help clarifying things here.

From what I understand, if the IAC is closed, the counts start at 0. Then, the MSII pulls back on the IAC to a certain number of counts before pushing the pintle back again to a number of counts to the "starting counts" and then the IAC moves from there?

Which is kind of confusing since what I understand about the GM system is that when the engine is shut off, the IAC pintle EXTENDS until it's closed (I've heard it do so when shut down as mine used to be LOUD, and I've also seen it do so with the IAC not mounted in the TB), and the system keeps it closed until the engine is started again, whereupon it opens to allow a certain amount of air into the engine to mix with X amount of fuel to produce Y engine idle speed... Like a carb's choke plate.

Seems to me things would be easier if, instead of setting IAC counts in the MS software, one just set a desired idle speed and the MS controller would handle the IAC accordingly for the amount of fuel injected...

[Maverick H1L]

Man, this "get rid of one problem and another pops up" thing is getting old...

I readjusted the valves again today. And reset the IAC counts (now at 170 hot), along with the VE table (needed more fuel for some reason).

The result? I'm now down between 26 and 28 kPa at idle. Not sure if it was the additional RTV, new manifold gaskets, or the injector o-rings, but it's down there. The evap canister is still giving me fits (I think... I hadn't yet adjusted the VE table when I disconnected the 2 vac hoses but the engine picked right up once it was disconnected).

New issue... Valvetrain sounds like a wasp's nest (rockers are all loose even though they're adjusted to max compression). Have to wait until the engine cools down before I can adjust them AGAIN. I'm definitely going to have to replace the rocker assemblies with stock 3100 parts...

[Maverick H1L]

Update:

Got the valves adjusted and now they're nice and quiet.

Need some serious help here as I can't get this thing right no matter what I do. If I can get it to idle right, it doesn't accelerate. Give it more fuel or less fuel in the VE table, it doesn't seem to work. I'm using the generated VEtable since my older ones aren't right, took a couple degrees out of the spark table, adjusted the upper end of the IAC curve, readjusted the warmup and afterstart enrichments, and I still can't get this thing to accelerate without bucking.

IAC counts are over 210 hot, which seems quite excessive.
Max VE cell WAS in the 130s, and the car absolutely refused to do anything besides backfire while accelerating (but idle was nice, when it wanted to idle). Now the max is in the 115 range.

I'm at the point where I'm considering selling this basket case and getting something more reliable. If there is possibly anyone on here who can give me a hand, especially in the local area, LMK.