Car won't stay started now.

So if it's guesses are that bad, my car would run like total shit? Because it didn't. It ran awesome. I'm going to do the old stock maf and see if the AF numbers jump up with the throttle.
 
Put the old maf back in, changed the setting on the translator to stock maf in/out and the AF on the scanmaster still jumps when I hit the gas :( You sure this isn't supposed to happen? :(
 
A stock style MAF doesn't plug into a translator. It plugs into the cars harness (just like it did in 87).


And I'm positive. If the ECM sees a MAF signal it reports the signal. Flooring it with the engine off will have a steady state reading since there's no airflow.

With a translator it can get kinda confusing. If the MAF is bad, the translator can still talk to the ECM. In your case that's not a factor is the ECM isn't being talked to.
 
earlbrown said:
A stock style MAF doesn't plug into a translator. It plugs into the cars harness (just like it did in 87).


And I'm positive. If the ECM sees a MAF signal it reports the signal. Flooring it with the engine off will have a steady state reading since there's no airflow.

With a translator it can get kinda confusing. If the MAF is bad, the translator can still talk to the ECM. In your case that's not a factor is the ECM isn't being talked to.
Click to expand...

I wonder what's causing my car to do this.
 
TurboBuRick said:
What is af # reading with gas on the floor?
Click to expand...

It's odd. It doesn't measure how deep my foot's in it-it measures how fast I depress it. Example: Just sittin there it's 4. When I floor it slowly, you'll see the numbers creep up to about 10 or so and then they're gone again right back down to 4. (with my foot still in it) It's only ten for that one second. If I mash it like there was a mustang next to me, it'll rise up very fast to a 20 or so, but then just like the last, go right back down the 4 again. It's like it measures rate rather than position, if you will. If you need a video, I could certainly post one somewhere for you guys to see. But with your experience I'm sure you already know what's up. Let me know. I'll do anything you want me to do. But if you ask me to trace wire, you must be super specific, because I'm not that good at electronics-haven't taken that class yet lol. You can't assume I know a base amount of knowledge, and that I'll already know where you're wanting me to look. I need colors, locations, everything lol. I know I'm not making this easy. :D
 
So now that's throttle enrichment?
You said if my numbers stay static-no change when I hit the gas pedal I'm good, and that if they change when I hit the gas pedal my equipment's malfunctioning. So... Now I'm confused.
 
If the maf signal is lost the chip will generate a maf signal based on the throttle position. The maf number will follow the throttle.

A momentary jump maf when throttle is hit is the gen2 sending throttle enrichment via the maf circuit.

Make sense?

Rick
 
So the AF numbers that are jumping around are different? So do the numbers I not want to see stay in relation to my throttle position? As in if I keep it half way down, the number stays there?
 
Turbo6Smackdown said:
It's odd. It doesn't measure how deep my foot's in it-it measures how fast I depress it. Example: Just sittin there it's 4. When I floor it slowly, you'll see the numbers creep up to about 10 or so and then they're gone again right back down to 4. (with my foot still in it) It's only ten for that one second. If I mash it like there was a mustang next to me, it'll rise up very fast to a 20 or so, but then just like the last, go right back down the 4 again. It's like it measures rate rather than position, if you will. If you need a video, I could certainly post one somewhere for you guys to see. But with your experience I'm sure you already know what's up. Let me know. I'll do anything you want me to do. But if you ask me to trace wire, you must be super specific, because I'm not that good at electronics-haven't taken that class yet lol. You can't assume I know a base amount of knowledge, and that I'll already know where you're wanting me to look. I need colors, locations, everything lol. I know I'm not making this easy. :D
Click to expand...


Do this 'test'. And do it EXACTLY like I type it here...

Go under the hook and unplug EVERYTHING MAF related from the car's harness. You should have a factory harness with a factory 3-wire MAF plug hanging loose with NOTHING attached to it.

then, go do the KOEO test while watching AF. That will show you what it looks like when the ECM doesn't have a MAF signal. From that point on, that will be your 'given' when doing this test.


When the factory came up with this method, they were counting on having a stock MAF talking to the ECM with nothing in between. when the MAF fails or comes unpluged, the ECM has a solution to get you to the dealer.

When you add a translator into the mix, it's possible for the MAF to fail and not give the translator any data. The potential troubleshooting problem can arise from the ECM having something to talk to (the translator box) but not getting good data due to faulty intel from the MAF.

-OR-....

You could possibly have a good MAF and a bad translator. From the ECMs point of view, since it sees the Translator first and thinks it's a MAF (sorta like people that go to Thiland to get laid and end up being surprised) if the translator flakes out, the ECM with report a MAF problem.
 
Got it.

Ok, I unplugged everything, put the key to key on engine off and mashed the throttle back and forth-same results. Plugged the maf back in, re did the test, same results. Started the car, it started up find and idled fine-pulled the plug on the maf and it sputtered and died. Whaddya say?


By the way, were you prior military? Navy maybe? Just curious.
 
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OK I just went out to my car.

With nothing hooked up from my car it reads 6 at idle and 10 at WOT. Rock solid and doesn't care about application rate.

With just the translator hooked up it reads 3 not matter the throttle. (It's set for an extender to it's reporting 1/2 of 'actual'. With a conventional chip it would be reporting 6)

With the translator and the MAF hooked up it reads 3 no matter where the pedal is.


Moral of the story, if the ECM has a MAF signal you should be reading 3 or 6 (depending on the chip) no matter what. If the ECM can't communicate it will be throttle dependent.

It sounds like you might have a wiring problem, a bad ECM, a wet/corroded ECM connector or a chip that needs to be reseated.


Nope, no military here. I like to sleep too late. :)
 
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I don't know if the test will work the same way when a gen2 translator is being used. It has tps based enrichments that use the maf circuit.

Try unplugging the translator and do the test again..

Rick
 
The 6 to 10 test was with nothing at all hooked to the car. It takes everything out of the equation.
 
Yea. I was a little confused. My translator hooks up wayyyyyy different than the 40 year old ones most on here use. Mines wired in to the ecm. You unplug it, the entire operation is dead in the water.

I have the turbo tweak in there.
 
The Scanmaster and the test should work with gen 2 ten pin connector unplugged. I just did it with mine. It worked.
 
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