MS2 Setup Help

[Maverick H1L]

Well, I went through a couple months ago and fine-tuned the sensor sample rates and got rid of the TPS and MAP spikes to get a nice flat signal. And my TPS wiring isn't anywhere near any plug wires. Only my 7x is... The TPS wire runs down the driver's front of the engine under the crank pulley, and down by the starter (RWD, remember) before coming up and joining the rest of the engine harness. The plug wires run around the back of the upper plenum.

It still seems like the engine doesn't like AE at all. Not sure what was with the WUE but it's gone now. I can get her to start pretty quick as long as she's not hot...

Now I'm just waiting on the fuel pressure regulator diaphragm I ordered on SUNDAY to show up... Supposedly wasn't shipped until Thursday and it's coming from Indiana... Anyways, the cheapo diaphragm in my FPR has gone bad and is spewing fuel into my intake. Between the excess fuel and the low injector pressure, my engine is running like crap over 2000 RPM loaded...

Bought and installed a set of 22# Ford injectors to replace the Multitecs I had installed. We'll see what happens... Runs great at idle, even with the low fuel pressure, so we'll have to wait and see what happens when I get the FPR fixed.

:edit: Also bought and installed a NEW IAC. Had to set the IAC steps quite a few points higher but the IAC is still acting the exact same as the old one... It still seems like it's not moving at all when cold (idle speed GOES UP) and working fine when hot...

[Maverick H1L]

Well, ended up replacing the entire pressure regulator... The first diaphragm was the wrong one and the second didn't help as the thing was still spewing fuel out of the vacuum hose port.

Now the engine bucks BADLY on acceleration. AE still disabled. What could possibly be the difference that acceleration was just fine before (except for a bit of hiccuping) and now it doesn't want to go AT ALL?

[Guest]

A lot changed.

With non controlled fuel pressure, assuming higher than it should have been and a ripped diaphragm would allow more fuel than needed to enter the engine, both through the injectors and through the vacuum hose. Now that the diaphragm is not damaged, the fueling dynamics will change greatly.

[Maverick H1L]

That doesn't make any sense. The tune is nearly the same as it was before the diaphragm in the original FPR went bad.

The only thing I can think of is the Ford injectors. I put them in before I found out the FPR was bad. Is it possible that there is a difference in the injectors? They're supposed to be Bosch IIIs, and from what I understand, they are a different style of injector with a different powering scheme?

[Guest]

That doesn't make any sense. The tune is nearly the same as it was before the diaphragm in the original FPR went bad.

The only thing I can think of is the Ford injectors. I put them in before I found out the FPR was bad. Is it possible that there is a difference in the injectors? They're supposed to be Bosch IIIs, and from what I understand, they are a different style of injector with a different powering scheme?

Well, it sounded like you made a lot of changes to the tune while the diaphragm was bad, which will change a lot.

A change in injectors can change a lot as well.

Basically, from what you are posting this seems pretty normal to me.

[Maverick H1L]

Here's the timeline:

12/29: Went through and adjusted crank PW to get consistant quick start. No issues with loss of fuel pressure associated with FPR diaphragm damage. Car completely driveable with no serious issues. Only minor tweaks to VE table made as AE was disabled a while before. Fuel injectors are 350 22# Multitecs from a Vette.
12/31: Ford 22# fuel injectors were sent through the mail by seller.
1/1 or 1/2: Started noticing extended crank time and necessary to hold accelerator pedal to start engine.
1/2 or 1/3: Ford fuel injectors arrive through mail.
1/3: Car inspected. No driveability issues except slight hiccup due to leaking FPR.
1/4: Installed Ford injectors. Later found FPR diaphragm torn. Ordered replacement.
---Car was NOT driven with bad FPR. Also due to bad weather.---
1/9: FPR diaphragm shipped from Indiana. For whatever reason, they held onto it for 5 days.
1/13: FPR diaphragm arrives and found to be not correct one (Aeromotive 13003 kit). Ordered Aeromotive 13001 kit.
1/15: Aeromotive 13001 arrives and FPR still spewing fuel. Ordered Summit FPR, which is overnighted.
1/16 (today): Summit FPR arrives and is installed. No changes made to tune since 1/3 (adjusted WUE and ASE a touch to cure stalling after start). Engine runs like garbage above 2000 RPM. Engine ran bad with bad FPR but this is 100X worse.

I'm going to limp the car back and forth to work tomorrow on the back streets and then I'll swap the fuel injectors (Multitecs for the Ford ones) this weekend to see what happens.

[Maverick H1L]

Sooo...

Yesterday, after going shopping for food and the car running halfway decent on the way there and like absolute crap on the way back, the Ford injectors got yanked and the Multitecs went back in. Most problems are gone now. Acceleration isn't easy above 2500 RPM (kind of levels off and then refuses to go, but at least it doesn't kick like the Ford injectors did). Not quite sure if I'm going lean or rich because the O2S reading drops to 0 during and skyrockets after I let off the gas.

VE Analyze Live isn't helping me AT ALL. 95% of the time it gives the message "O2S out of range" and doesn't do anything at all. Kind of ridiculous when the O2S voltage is reading just under .4V or just over .5 . Guess I'm going to have to rely on the EGO Control and Automatic Mixture Correction. And the analyzer in MegaLog Viewer only analyzes the first 5000 records of a datalog (whatever that means) because I refuse to shell out another $30 for one lousy function of the program.

[caffeine]

Good to hear you're starting to fix all the problems.

[Maverick H1L]

Is there somewhere I can find a chart with NBO2S volts vs. AFR? It might help me out a bit... Looking at the log, 2 issues seem to have become apparent. 1. O2SV staying about .68V and 2. O2SV dropping during acceleration to 0 and staying there. Looks like I'm running rich, but dropping the VE numbers while going makes things worse?

[robertisaar]

low volts = lean.

hovering at .68, i can't really comment on, but your results of seeing worse performance with less fuel being delivered agrees with the O2 sensor.

[Maverick H1L]

Ok, I backed fuel out of the VE table AND turned down my fuel pressure a bit and got some get up and go back.

Seems I'm still a bit rich but I'm heading in the right direction.

Reason I'd like some sort of O2 volts vs AFR table/chart is to help figure out what I'm looking at. I'm looking for about 15:1 at cruise, and I know that's not 0 volts.

Right now, I'm working on getting some sort of solid mount for the DB9 connector as it seems my ECM mounting has pulled on it and it needed to be straightened back out. Also still having an issue with some sort of connection error via the factory harness connector where if the harness connectors' terminals shift ever so slightly, the engine runs like crap. I've already gone through and pulled each and every terminal out of the connector bodies and pinched them to make them tighter, to no avail. I think I'm going to have to modify the ECM mount to give a little more slack in the wiring, which is going to be difficult considering I'm running a dash out of a 93 Camaro and there isn't really any room under there...

[45es]

Here's a really old link that may help with the o2 vs volts question. Scan down the page to o2 sensors and indicators paragraph. There is some data from notes Bruce made while observing a nb sensor.

[carbon]

Here's a really old link that may help with the o2 vs volts question. Scan down the page to o2 sensors and indicators paragraph. There is some data from notes Bruce made while observing a nb sensor.

No link?

[45es]

Sorry. Like I said it is a really old link with just a little data from some notes that were made then.

Also, if you look in the MS manual there is a little data regarding nb o2 voltage vs afr.

http://www.diy-efi.org/gmecm/papers/tunetip.html#o2

[Maverick H1L]

Well, I finally broke down and ordered an Innovate LC-1 wideband kit. Should be here next week.

Removed the MS from the car and fixed the issue with the DB9. And changed the mounting under the dash (flipped the ECM over).

Turned fuel pressure back up to 43 PSI. Autotune is working when it wants but keeps adding fuel, so I backed the Autotune numbers out of the VE table and I'm going to turn the fuel pressure up some more (autotune keeps adding fuel across the board). Then I'll try autotune again.

Which means I'm going to have to retune the crank PW, ASE, and WUE along with my IAC steps (or the idle part of the VE table again).

Still having the same issue with the IAC. Except that the idle speed doesn't change now every single time I start the engine above full cold start. Now I have to restart the engine at least once after cold start. Startup idle is about 1500 and it goes up to about 23-2500 unless I shut it off and restart it again. Still not sure why the MS is doing this. And this is between 2 IAC motors. Idle intake pressure, when warmed up and idling about 1100 RPM, is still about 28 kPa, so no vacuum leaks.