Mass air to Speed Density?

JenkinsBS

Founding Member
Apr 16, 2002
1,001
1
39
Washington
Whats up guys, long time no post :p But ive got a quick question about my old Mustang that i sold to my Grandfather.

I did alot of work to the engine on the car (bored to 306, ported polished e7 heads) and had bought 30# (or 33#, whichever the red ones are) and a MAF that matched the injectors. I never got the project finished which is why i sold it.

Well my Grandfather got the car back from the shop he took it to, and i was just looking at how they did things, and have a few concerns.

The main one is that the MAF is gone, and the stock 16# (yellow) injectors are back in. The car has a rough idle and lack of power on acceleration, but wants to get up and move after you start letting off the gas, and you can definatly smell that it is running rich.

Could this be caused by the removal of the MAF from the car? Or just a Timing issue.

I also had a 6AL msd box i gave to him, but they didnt use it (i dont know why), but said they couldnt get it to work until they did what they did... im thinking they just took the good parts and sold them for money personaly...
 
I thought Id would ask cause if they didnt change the computer, he is running a SD car with a ecu for mass air.

Im kinda curious what could or would happen if thats the case
 
Need a little more info. What year is the car? It was speed density before and you converted it to mas air? How did you do it?

Now the maf is gone completely? And the stock 19# injectors are back? So it's running maf less? If so, what computer is in the car?
 
I need to, problem is the shop isnt open on the weekends, and i work mon - fri, getting off at 5, shop is closed by then.

So the best thing i think i can do at the moment is inform my Grandpa of whats going on, and see if the shop is smart enough to fix it.


The car when i bought it was already converted to MAF, i did have to replace the ECU one time, i think i got it out of an 89, which from what the mechanic i was dealing with said would work, and it did.

So i just told him that we need to find out if the shop replaced the ECU back to an older one, or just to put the MAF back on there with the Red injectors i had already put in (the MAF and Injectors were calibrated by Pro-M), and the problem should be fixed

Is there any problem putting 30# injectors on a stock motor?
 
Its my god darn lucky day today! I got my pony back! My Grandfather gave it back to me, because he had planned to all along for my birthday! :jaw: Now i get to put on my nittos, lowering springs, and exhaust!

So the question is basicly the same, I found the MAF plug just hanging in the engine bay, no MAF sensor plugged into it. The car idles fine after a few moments of kind of pressing the gas pedal to keep it from dying, but when driving, it kind of hesitates before it takes off...

Is this typical of what would happen if no MAF sensor was attached and the CPU is looking for it? Im planning on picking one up tomorrow, but dont know if the shady shop would have done somthing to bypass it... any suggestions or indications i can look for?
 
Pull the pass kick panel off and look at the ECU. Get the computer code off it. We need to know if it's running on a MA computer or a SD??

Most likely, the car has a MA comp and the shop just disconnected the MAF and found it ran better. I bet if you ran the check engine codes, your find a few. That will be the next step after confirming ECU
 
Ill confirm the ECU code once i get home and look it up to make sure its out of somthing higher than an '86.

I really just hope the shop didnt do anythng to the MAF sensor wires (clip and tape and just f it up in general) so i cant put the stock MAF back on.
 
Ok, pulled the kick pannel off, computer says em073, which from what i am reading, is what is needed for the MAF conversion, so since the MAF sensor isnt hooked up, it is causing some problems.

Im about to go try to get a MAF unit now, hopefully this corrects some of the hesitation issues.

On a side note, the battery died this morning for no apparent reason. I can only assume alternator, but do not want to take it off to bring it to a place to test, is there any way to test it w/o taking it out.

Im thinking of jump starting the car to see if continues to run, and if it dosent, than the alternator is bad...
 
alright, so i jumped the pony, holding an idle after the cables are off, so to me that means the alternator is good, just have a weak battery, so ill be getting a new one today along with the MAF unit.

Anyone else have any other ideas?
 
That is a Mass air computer.

So you have a MA computer, 19# injectors and stock MAF??

As for the alt issue..how did it behave before it died? Did it slowly lose power? or did you try to start it and car was dead? Do you have a digital volt meter?
 
That is a Mass air computer.

So you have a MA computer, 19# injectors and stock MAF??

As for the alt issue..how did it behave before it died? Did it slowly lose power? or did you try to start it and car was dead? Do you have a digital volt meter?

Stock injectors, no MAF unit at the moment, the wire it connects to is just hanging there, the shop couldnt figure it out??? so they just disconnected and tossed the piece, dont know where it is now, not going to find out.

As for the car dying, i was backing out my driveway this morning, killed it 2 times, tried to start it on the 3rd try and it just half way cranked, and kept doing that.

I just let the car run for about 10 mins with out the cables, going to try to start it in a minute, see what happens

*edit*
Tried to start it, Now its just a fast clicking sound...
 
new battery fixed the starting issue beautifully.

now im just waiting on the MAF sensor to be delivered from a warehouse in federal way. I should be picking it up within the next few hours, hopefully thats all i have to do to get it to daily driver status.
 
Plug it in and dump the codes. Let's make sure the car's really happy. Kinda strange for the shop to just remove the maf.

To be honest, kinda thinking those parts are on someone elses car now. Shop saw your grandpa, and some tech took the injectors and maf and swapped them out and jut got the car to run. Prob figured he wouldn't miss them.
 
Plug it in and dump the codes. Let's make sure the car's really happy. Kinda strange for the shop to just remove the maf.

To be honest, kinda thinking those parts are on someone elses car now. Shop saw your grandpa, and some tech took the injectors and maf and swapped them out and jut got the car to run. Prob figured he wouldn't miss them.

Thats what i told him. I gave him roughly $300 worth of parts to put on the car, and the only one i can still see on there is the pro 5.0 shifter, which im thankfull for.

Plus he paid me for the car and gave it back for free, i cant complain :D


So basicly just hook up the MAF, take the positive lead off the battery for like, 20 minutes, then should be good to go?
 
Thats what i told him. I gave him roughly $300 worth of parts to put on the car, and the only one i can still see on there is the pro 5.0 shifter, which im thankfull for.

Plus he paid me for the car and gave it back for free, i cant complain :D


So basicly just hook up the MAF, take the positive lead off the battery for like, 20 minutes, then should be good to go?


you remove the negative if you are going to remove a cable.

just like you always remove the NEG. cable 1st before removing the POS and always put the NEG cable on last