Who has installed a PRO-M mass flow sensor?

wastintime · 02-09-2005, 01:51 PM

Hi everyone,

I know some of you have installed a PRO-M mass flow sensor, i've seen posts about it. If anyone has installed a pro-m mass flow sensor on their car I could really use some help right now.

the current problem is this: I have installed the PRO-M mass flow sensor kit. According to them everything is hooked up correctly, and should work, but the car doesn't start. I'm starting to think mine is the first 3.6 kit they've ever made. It was terrible how many other parts I had to buy just to get it installed.

I don't think the 3.2 carreras are that different, in fact, I thought they used the same airflow sensor, and if they do, then hopefully I was just sent the wrong wiring, but basically it looks like the DME in my car wants to see a temp reading coming off of the sensor in k ohms, and an airflow reading in volts, and their harness is wired for the opposite. Does anyone know if 3.2s are different than this?

Another question is this:

The airflow sensor uses a 4 pin connector, pin 1 is for the air temp, pin 2 is for the airflow, pin 3 may be power, i'm not sure, and pin 4 is the ground/signal return. They had me not hook anything up to pin 3... does this correspond to anyone else's installation?

I'm really desperate for help guys... thanks.

89911 · 02-09-2005, 03:33 PM

I've got a Huntley Racing MAF sitting in my basement that I took off my 3.2. It also works for 964's so it may be similar.

In the instructions, it has the connections needed for a 964. If these look like they may help, my instruction for a 964 says:

ECU signal input (Connect to DME terminal #7)
ECU Temperature Input (Connect to terminal #44)
Throttle Position Switch Signal Output (Connect to terminal #52)

All other connections are power, grounds and lighting.

I am also selling this if anyone is interested.

asphaltgambler · 02-09-2005, 03:38 PM

Does'nt it have directions?? What year is your car? I thought the 3.6 had Mass by then.

That thing has got to have 12 volts to work, gorund, air flow (metered) and temp. That's four wires.

wastintime · 02-09-2005, 06:39 PM

lol, asphalt, of course it didn't come with directions... and that i'm not mad at, they just forgot to put them in the box, but having followed the directions on the phone, it doesn't work. No, 3.6s didn't have them until the 993s.

okay, the car's plug only have a 5v power source, so... imagine the 12vs is independant of the other wires. You then have ground, airflow, and temp... these are the three wires that we hooked up on the 4pin connector... this is what bothers me that we left pin 3 hooked to nothing, although Pro-M claims this is how all other 911 applications have worked.

i'm not sure if the diagram in the instructions can be taken word for word since it's a completely different kit, but... without the throttle switch and panel lights, it looks about the same as how mine is wired. The only thing that could be different is that on my kit, both ground, and signal return wires go to pin 4 on the car's connector.

wastintime · 02-09-2005, 06:42 PM

btw, thanks for the pics '89 I appreciate it

ZCAT3 · 02-10-2005, 06:35 AM

Andrew - I got you PM. Unfortuantely I sent my notes on the install off to the person who I sold the MAF to. Just out of curiosity, do you have the MAF tuner module and if so is it plugged in? The car will not start without it plugged in. I do seem to remember that one of the pins in the car's MAF plug was left unattached when I hooked up the MAF.

siverson · siverson's Garage

Yes, I got a used Authority MAF kit to work on my 914 (w/ 3.6), and uses the PRO-M sensor.

I only used 3 of the 4 wires because I believe the PRO-M sensor does not have air temp. PWR on the factory AFM plug is +5V as you pointed out, so I ended up getting +12V from the then unused blower plug which was nearby.

In my application, the Authority chip did need to be installed for it to work. The scaling/mapping is entirely different and won't start without that correction.

Good luck!

-Steve

wastintime · 02-10-2005, 07:52 AM

Bill, yes I do have the maf tuner plugged in... right now they're getting me to check it to see if it went out without being programmed correctly.

wastintime · 02-10-2005, 08:34 AM

well, my new problem is that i don't have a laptop old enough to have a serial port, and i don't know if it's the adapter or MAF tuner that's not working

project935 · 09:04 AM

I think you can get serial-to-USB adapters at your local computer store.

Not that this will help, but ...
I stopped by Pro-M a couple years ago (local here in Detroit area) when I was looking for some assistance on a Mustang project of mine. They kinda just roughly develop their stuff and float it out on the market leaving the customers to figure it out. They got rid of all their chassis dyno work (unless it's one of their personal projects). About the only tuning they do is flowbench testing of their MAFs for different pre-MAF restrictions (filters, elbows, etc).

About the only useful tip I got from them is that MAFs hate fan 'noise' - make sure your air filter is either enclosed or completely out of the fan wash. A lot of my problems went away once I enclosed my air filter.

I seem to recall they had a somewhat informative website - www.pro-flow.com

wastintime · 02-10-2005, 02:18 PM

yeah, i ended up buying two different usb to serial adapters... neither of them worked, i don't know if that means they didn't work or the tuner didn't work.

wastintime · 02-10-2005, 02:34 PM

you know how horrible it is when you have so many hours invested in a project, and you've already modified enough stuff that you just can't bring yourself to give up and go backwards.... i'm hoping i know when that point should be.... *sigh* aftermarket b@stards...

wastintime · 02-10-2005, 03:09 PM

HA! the car started! I should probably be more excited, there are some weird issues still going on. First of all, it had really been bothering me that the car wanted to start so badly, so... i started playing with the gas pedal while starting it... it only startes with the gas pedal about half open... now since I know the airflow signal was too low, I'm thinking that maybe it finally draws enough air over the wire to be normal at about that throttle position and let the car start. Who knows... once it started it didn't want to run for a little, but then the idle smoothed out and it actually was not running that badly... now this is going to sound really screwed up, but i swear the exhaust smells funny all of a sudden, and i don't know how to describe the smell... it may be that i ended up starting the car with the garage door closed since I didn't really expect it to start and I just noticed too much exhaust as the smell, but who knows.

the bad news is the check engine light never goes out, but this could still have to do with the airflow signal being wrong, I just don't know... and since I can't get the laptop to talk to the tuner or vice versa I'm really kind of afraid to drive the car and see what will happen... lol, this was definitely not worth it...

wastintime · 02-10-2005, 03:51 PM

oh the joys of having an adaptive control unit... now the will not fail to start! not that i'm complaining, but it's just a pain in the but... it's the old catch 22 about adapting the DME with the bosch hammer... you have to adapt it for it to run, but it has to be at operating temp to adapt it... oh well. At least the car seems to like to sensor now though... I did confirm by looking at the airflow LEDs on the MAF tuner that the airflow signal is very low, it never really gets out of the idle range, so if I can just get a damn laptop to talk to it I can adjust it and hopefully drive it after that.

ZCAT3 · 02-10-2005, 08:06 PM

Andrew - it took me a while to figure out how to tune the MAF using the software. Of course I had no problem hooking it up to my laptop. Hopefully they gave you instructions for this, but as I remember it you would download the map from the tuner into a file on your laptop and then you can change the map point by point. You then upload the changed map into the MAF tuner and it is your new baseline. You cna make changes with the "pot" tuner dials on the MAF tuner itself as well. What I did was once I got the car running o.k. with manual tweaking, I took the car to a dyno and ran some tests for A/F ratio and power. I saved a few of the maps from my dyno day - one that was an the lean side and one on the richer side. I then fine tuned the map using the tuner software later. The car ran great, started fine, idled fine - etc.

wastintime · 02-11-2005, 03:28 AM

Thanks Bill, sounds like i definitely have a problem then because it absolutely will not talk to the laptop.

wastintime · 02-11-2005, 11:00 AM

Well, we finally got the computer and the tuner talking... it was a computer problem, but just another really insanely annoying thing.

well, I think the car is actually running pretty well. The check engine light won't go out so I disconnected the battery, and I'm going to wait and see if that clears the fault memory, if not I may try to drive it to work and grab a bosch hammer and clear it out. I'm hoping that throughout this process somehow it just had some faults bad enough that it doesn't want to erase them without having the hammer put on it.

wastintime · 02-11-2005, 01:30 PM

The car actually drove pretty well... disconnecting the battery worked, and the check engine light never came back on. The car drove fine the first time i drove it, but in heavier traffic I noticed a surge at idle. I can't decided if it's a rich or lean surge, but it doesn't like initially taking gas, and it backfired twice coming off of idle.

I don't think I'm going to drive it much more until I get a wideband O2 sensor on it and really get the mixture tuned right, because right now I'm afraid of damaging the motor if I drive it hard. Tomorrow my boss and I are making a bracket to support it in the engine compartment.

Anyway, I guess I'll post more as stuff develops.

ZCAT3 · 02-11-2005, 01:45 PM

Andrew - if it hesitates or stumbles off idle, then it is likely running rich down low. After I got it tuned in nicely on a chassis dyno, the most difficult issue I had was getting it to not be rich at the low end. If it is too lean, you probably would not notice anything off idle, but would upon acceleration - the most obvious sing is pinging. I would highly recommend you book an hour of dyno time and get it tuned to a decent A/F ratio. You cna then fine tune it with the software on your own. Good luck.

wastintime · 02-11-2005, 02:27 PM

Bill,
Yeah, I know I really need to tune it before driving. I'm probably not doing it on a dyno, but we've got a wideband O2 sensor at the shop and we're just going to use that to tune it. I will probably lean it up some before driving it over there tomorrow though. Thanks.

btw, I meant to say that the sound is great... much more sportscar sound than the airbox.

Thread Tools
Show Printable Version Email this Page
Rate This Thread
Rate This Thread: