how critical is the mass air meter

[llvllanifest]

i have a question guys...i just swaped body..from an 87 lx 5.0 to a 90 gt ..my question is..my 87 didnt come with a mass air meter.obviously..but right now,,i just got engine and everything transfered to the 90 gt body..and i just tried to start it up to make sure everything was in good shape and that it started up..well..it fires up and it dies within 5 seconds..if i try to give it gas..it stalls quickly..i know i need the mass air meter..but i didnt think it would cause it to not run...my question i guess is..do i need the mass air meter period to get the car to run?

 

[HISSIN50]

It's arguably the most important sensory input the computer receives.

 

[Nibbie]

I would think if it was disconected it would run horrible and make the check engine light to come on. Say if i unplug mine and start it, it will start but run crappy and a check engine light will come on. I dont think it would cause it to die with in 5 seconds. It might be somthing els, is it throwing a check engine light or any other lights??

 

[vristang]

There is a lot of potential for error in the conversion you just did. You have not provided anywhere near enough detail for us to help you...

Yes, the car should run with out the MAF, assuming there are no other issues...

The 87 was SD, and the 90 was MAF?
What ecu are you using?
Did you hook the BAP up to manifold vac?

Better yet, just start by pulling the diagnostic codes from the ecu...


Let us know,
jason

 

[llvllanifest]

no no light are triggered..but i just noticed that none of my gauges are working..so i assume it a fuse...on that circuit along with the gauges..it includes what they call the carburetor circuits..could that be it also...and the car had gas in it as well...could it be bad gasoline also..i just bought the body so it could be old gas too

 

[llvllanifest]

as far as the ecu and and everything else..the car i bought came with everything..wiring processor..ect..all i did was put in the 302 and tranny which is all it needed ..i also hooked up the bap too

 

[mrmustangman357]

a fuel issue would usually let the car start and immediately die. maybe it is the cold start circuit. My car occasionally dies when i start it but if i crank it again it acts like theres no problem. if you give it gas will it stay on?

 

[vristang]

as far as the ecu and and everything else..the car i bought came with everything..wiring processor..ect..all i did was put in the 302 and tranny which is all it needed ..i also hooked up the bap too

This is where things get sketchy...

IF you have a MAF ecu, then the BAP should be sampling Barometric air pressure, not Manifold pressure.

If you have a SD ecu, then the MAP should be sampling the Manifold pressure.

A MAP sensor and BAP sensor are the exact same parts (same part number), but they sample the pressure of the air from different locations.
MAF ecu's need to know Barometric pressure
SD ecu's need to know Manifold pressure


What is the catch code of your ecu?

jason

 

[Alexa]

I had a Mercedes as my first car. It was not new. It didn’t have Mercedes Benz Air Mass Meter. At first, I though it was fine without it. But later on, I realized that there is something in it that is very important. It is the one that measure the bulk of air intake that passes through the filters, which helps in the accurate calculation of the amount of fuel that is to be injected for better combustion efficiency and less fuel wastage. That is the only time I decided to put one in my engine.

 

[Mustank]

If you're using a MAF ECU, you should have a MAF sensor - so even if that's not your problem, you need to buy one. I assume your car already has the correct wiring harness for it, so it won't cost you too much. Get a MAF, see if it helps - if it doesn't, start looking at other potential problems.

I'd also recommend draining the gas tank and replacing the fuel filter - then fill it back up with high octane gas and some injector cleaner. If the car sat too long there is probably water in the gas.