Engine 87 lx mass air conv. Now codes...

[KZGUNS]

So did the conversation and now I’m getting 66 and 22 ugh!
I have battery voltage at the maf sensor.
Not sure what to check next. It’s a new bbk sensor.
Idle is rough and RPMs seem to hang. ECU is from encore mpw.

I totally see why people go backwards to carb. Which I definitely don’t wanna do. But I get it lol

 

[KZGUNS]

Ok a trip around the block cleared code 22

 

[KZGUNS]

So the plot thickens. When I probe brown wire (signal ground) the rough idle went away and everything smoothed out. Once I pull the meter probe it runs rough and stalls.

 

[KZGUNS]

Can anyone point me in the right direction? Please

 

[KZGUNS]

When I take reading from the brown and blue wire while running the idle pops to ~1200 and smooth running and I get 1.15v
Why does it seem to smooth out when that’s being tested?

 

[KZGUNS]

The 2 signal wired give me .4 ohms from plug to ecu plug at pin 50/9
I tried to get an ohm reading from maf plug to ground on each signal wire and I can get a reading? Could this be the issue? If so what’s the next test?
These readings were all done with battery disconnected by the way

 

[KZGUNS]

@jrichker I’m following your test procedures. Do you see where things are going wrong from the data I provided?


Is this the right sub forum?

 

[General karthief]

Your in the right forum, give it some time, jrichker will help you out.
sorry I can't help ya.

 

[KZGUNS]

Thanks, just frustrated.

Did some more testing. I do quickly get ~17k ohms on the brown wire to ground but it goes to zero right away. Nothing on the blue though. This is with plug disconnected from maf sensor. I’ve checked all my repinning and splices and they are all good. I did this many times now. I cleaned and resecured the ground at the ecm as well.

 

[General karthief]

There are 4 grounds in the engine compartment that are important for the computer and gauges to work properly, drivers side back of head to firewall, injector harness to engine, computer ground between the battery and solenoid and the battery to engine ground, I think I'm missing one, I'll look and get back to you.

 

[KZGUNS]

More testing... I switched my ohm meter to read up to 200k and I get 100k on blue and 30k on brown

 

[KZGUNS]

Quiet over here in the 5.0 tech area.

I have a factory replacement maf and housing that I’ll have today to see if I have a bad maf from bbk. I called lmr today and he’s gonna swap out the bbk I bought since he’s leaning toward a bad unit. I’ll update later.

 

[General karthief]

Check out the surging idle checklist in the tech/how to thread, it gives you steps on checking things like the maf. I guess I should have mentioned it earlier.

 

[KZGUNS]

Ya I did. My wiring etc seems to check out so I’m hoping it was a bad sensor from bbk.

 

[KZGUNS]

Ok it runs fine with factory replacement maf. Getting about .8 volts at idle with a 900rpm idle. I’ll dial it down a bit. Happy to get this figured out. Hopefully it’s not a fluke lol

 

[General karthief]

There are instructions for resetting the base idle in there too.

 

[KZGUNS]

Thanks! I’m all too familiar with that now. Lol one thing I’ll say is I’m good with cars etc. built many engines but this FI is all new to me but I’m learning quick!

 

[KZGUNS]

Also code is all gone now.

 

[General karthief]

Been fooling around with fox efi long enough I have trouble remembering what a carb looks like.

 

[Mstng93SSP]

My wife said carbs are bad, she told me high protein, low fat is the best diet.............