Took car too shop due to light on they said mad replaced 3 times and now when it's plugged in car goes too about 3000 rpm and then bottoms out sometimes dieing Today I replaced Egr at recommendation of 2 mechanics plugged Mas back in and it's still doing it.
engine light on (94) hard to get specific codes
Backfires threw exhaust
Blowing black carbon from exhaust
Mpg 8 n twn 17 hwywy
Black smoke from rear and side of vehicle
NON OF THIS STARTED BEFORE REPLACING MAS the only reason I had codes read was because light annoyed me car ran great
I have replaced Mas, Erg, and brain please help me
I need to know what year your Mazda is and engine size?
The sensor you are referring to MAD would that be the MAF (mass air flow sensor)?
Are you sure the code is 94, I can't locate it any where.
If you can have an auto parts store like Auto Zone scan your vehicle that would be a good second opinion and they do it for free. While at Auto Zone check the part number to the sensor you keep plugging in it could be the wrong part. You said you didn't have the problem until you replaced that part.
Get back to me with the updated information when you can, we can diagnosis the problem further from there.
It is a 94 Mazda Navajo 6 cyl 2 wheel drive. I am not a mechanic in any way but when it's a couple bolts it's something I can do.
Everything on this motor reads Ford Explore including fuse box.
I took it too a shop for code reading, it cost a 120.00 for them to tell me the mass air flow sensor and followed that with saying they'd have to read it again after that because it might lead to something else. I replaced the MAF myself 4 bolts, got that I started revving up and almost dying. So I took it to Tires Plus, They kept it 3 days and didn't have a clue they thought it was a bad part so they replaced it twice and recommended the brain inside the car so again 4 screws. I replaced it but no help yesterday at recommendation of 2 mechanics. I replaced erg it got worse the high idle has stopped but now the idle drops so low it dies or almost dies I can not find a free code place in mobile Alabama due to age of vehicle I also can't afford the 120 an hour the shop wants I'm home on medical leave income extremely limited please help please it's my only vehicle.
You didn't mention if you can drive the vehicle. A relearn process is needed which is why the mechanic said it may need to be scanned again so they can monitor the other sensor for this process.
When you replaced the PCM (computer) you lost all of the stored memory for some sensors needed for proper drive ability. Even though your engine is racing and then trying to stall there is a relearn period where you would need to drive according to the manufacturer is about 10 miles for the new computer to relearn the proper values of the sensors which include the mass air flow and the idle air control valve.
Also check all of the rubber ducting from the mass air flow sensor to the engine making sure there are no cracks or air leaks, these cracks can make the mass air flow sensor give false information to the PCM causing drivability issues.
After you start the vehicle just put it into drive with your foot on the brake and when it tries to stall press on the accelerator just enough to keep it running. This can help with the learning process. If and when you can keep the engine running in park or neutral with out your foot on the brake try to drive around a little to see how it operates. Remember, when you first start to drive it will not run good. The longer you can drive it the better it should run as the PCM learns.
Try these suggestions and get back to me with your results
May not get much help from a part's store identifying trouble codes because this is a pre-OBDII (1995 or earlier) system.
Here's a link with instructions to pull codes with the use of a digital multimeter (voltmeter).
Disconnect and reconnect the battery. Start the engine and tell us if the light comes on immediately. If it does, that directs us towards a hard electrical failure. If it takes a while of running badly before the light comes on may indicate a mechanical or fuel related problem.
Either way you need to accurately read the trouble code before going any further.