Hello People,

I’m currently having some issues with my 1996 Mazda protégé, 1.5L. Actually the car is like one block from my house in front of a store because it won’t start lol.



The car starts when it’s cool, but after driving it, when I turn it off, if I’m going to use it again it won’t start. The car does try to start!


The issue started some time ago, the check engine light came on, and when id drive it, the car “sort of loosed the power” if I hit the gas pedal too much and would start to slow down not responding. Things I’ve done:


1. 1. Took it to a mechanic, he drove it (he saw it didn’t respond when stepping on the pedal), covered with his hand the muffler hole and told me there was “no pressure”. He then told me to check the catalytic converter. I took the car to a muffler shop they ran test on it and the muffler and catalytic were fine.


2. 2. Took it to a second mechanic, told me to take it to a shop for a computer diagnostic. I got the diagnostic and they told me it was the mass air flow sensor (MAFS). I was able to get a new mass air flow sensor from a seller on eBay. Once I installed the MAFS, the car wouldn’t turn on and just shut down by its self. I contacted the seller, resend the item, and got a second one and it still does the same thing.


3. 3. While waiting for the response of the seller for me to resend the bad MAFS, a friend of mine lend me a computer diagnostic tool, and I tested the car with both (my MAFS and the new MAFS). With the old MAFS, I got Code P1195 - Baro Sensor Circuit. Kinda weird because at the computer diagnostic shop they told me it was the MAFS. With the new MAFS, I got the Code p0100 (Mass or Volume Air Flow Circuit) and this is a MAFS problem.

4. 4. I started looking on the web and found where the location of the Baro Sensor Circuit was and it had a loose line!!! I put it back on and now the car responds to the pedal perfectly, but the check engine light would still come on (meaning that the fact that the car wasn’t responding to the gas pedal properly is independent of the problem the car is having not starting after tuning it off). And that is a fact, as I stated my car is one block away!!!!


****I have noticed that the gas pump does not activate when the car doesn’t want to start. I have removed the gas lines and tried to start it and it doesn’t spit out gas. I have taken out the gas pump twice and tested it directly from the battery and it activates! I have tested the electricity that goes to the gas pump and there is electricity!!!!!

Hope you guys can give me some help, this car has been the work horse of the house, best car I have had, but it’s starting to drive me nuts!!!!!

 

Ok first question, and dont take this wrong but you would be surprised at how often this happens, do you have enough gas in the tank? If you put more in the tank (even if you know there is fuel) does it start then? If your getting power to the pump (like you tested) and its not pumping fuel the pickup tube could be blocked/broken and only works when the tank is fuller. If you power the pump directly does the car start then (you didnt say it did or didnt)? If its based on warm/hot temperatures I would say either the pump is dying or your having vapor lock issues (not impossible on fuel injection, more likely with a weak fuel pump), when was the fuel filter last changed?

 

I changed the fuel filter about 2 months ago. The last time (yesterday) the car would not start it had half a tank of gas. When I power the pump directly I meant that I remove the fuel pump from the tank, go to the front of the car and connect cables from the fuel pump direct to the battery (their is no way the car will start with the fuel pump out of the tank). And no, I cant recall trying to test the fuel pump after testing it outside. That was something that crossed mi mind (the posibility of the fuel pump "reactivating" after testing it directly from the battery). I have heard (don't know for a fact)that the energy the pump receives directly from the battery is much more than the electricity that the fuel pump normally receives resulting in an "activation" of the fuel pump.

Thanks for the timely reply!!!

 

I would hook up 12V to it while its in the car if you can reach the wires, if it starts then you have an issue "upstream" in the circuit, if not then something "upstream" of the pump. Yes you do lose some voltage in the distance from the battery to the pump but the voltage drop SHOULD be negligible and not affect it to any degree, now if your only getting 9V at the pump then something is wrong like loose/corroded wires/connections. Some cars do not turn on the pump until the computer sees either crank rotation or even oil pressure, I am not sure if the Protege has this kind of system, my 323's pump does not run with the key but only with the engine turning so if you have a bad sensor on the engine it could knock out your pump.

 

Locate the fuel pump relay it should be in the engine compartment. There are probably two other interchangeable relays with it. Swap it with one of them, give that a try. If nothing, you need to check for voltage with key on to the relay open contact terminal. If nothing, it might be a fuse. That particular circuit is hot with key on (fused). The relay coil is controlled via keyswitch, and probably generated from the ecm, with inputs to it to determine if it wants the relay to energize. I don't have your circuit to look at, but this is a suggestion, if nothing else to rule out the pump or not. If the relay is energizing, and you have the 12 volts, pump won't run, it's pump. If the relay isn't getting energized, pull it, with a paper clip go across the relay open contact terminals to the 12 volt source, pump runs, or dosen't, dosen't run, pump is defective, or wire issue to it.

 

You had codes. Made some changes. Did you re-set computer after? You still may want to do this to re-set ECU anyway!
Please do the Following: Disconnect negative terminal of battery, press on brake pedal for 5 seconds. Let car sit for 10-15 minutes. Re-hook up battery. Start car and let idle for 10 minutes. Now the ECU is re-set and re-learning has begun. 50-100 miles for re-learning.

 

Thanks guy's!!!

The car is currently running so I wont be able to know well until it goes out on me again. I'm trying to contact the seller of the mass air flow sensor for a refund.

One thing i forgot to mention was that the mechanic told me the fuel pump was good, that he had tested it. When I asked how??? He responded that while the car was on, he "chocked" the gas line (I believe that is the one that sends back the gas to the tank) making the car "tremble" because it was flooding with gas towards the engine.

I'm still stuck on mass air flow sensor!!!!

 

hey do you have an owners manual for your 96 protege that u can make a pdf of and email to me? would greatly appreciate it if so...

 

The first people to run a scan were the people from Autozone and they told me it was the "Mass Air Flow Sensor", I got it, and once installed, the car started "trembling" and turned off.

After that:

I scanned the old Mas Air flow Sensor, I got the code: p1195 Baro Sensor Circuit.

I scanned the new Mas Air flow Sensor, I got the code: p0100 Mass or Volume Air Flow Circuit.

The mechanic did the same and he got the same results with a different scanner.

I sent back the "faulty" Mass Air Flow Sensor, within days got a new one (the same brand) and got again the same result as the one sent back: p0100 Mass or Volume Air Flow Circuit.

With my original MAFS, the mechanic was able to erase the check engine light, but it comes back. Neither of us were able to reset the check engine with the scanner on the new MAFS. While trying to reset it the check engine light would blink back on.

Given the 2 issues with the MAFS, the mechanic final diagnosis was that the vehicle had a bad flow meter!

Just wished I new someone with the same car (good MAFS) to test mine

Thanks in advance for the timely reply!

 

The first people to run a scan were the people from Autozone and they told me it was the "Mass Air Flow Sensor", I got it, and once installed, the car started "trembling" and turned off.

After that:

I scanned the old Mas Air flow Sensor, I got the code: p1195 Baro Sensor Circuit.

I scanned the new Mas Air flow Sensor, I got the code: p0100 Mass or Volume Air Flow Circuit.

The mechanic did the same and he got the same results with a different scanner.

I sent back the "faulty" Mass Air Flow Sensor, within days got a new one (the same brand) and got again the same result as the one sent back: p0100 Mass or Volume Air Flow Circuit.

With my original MAFS, the mechanic was able to erase the check engine light, but it comes back. Neither of us were able to reset the check engine with the scanner on the new MAFS. While trying to reset it the check engine light would blink back on.

Given the 2 issues with the MAFS, the mechanic final diagnosis was that the vehicle had a bad flow meter!

Just wished I new someone with the same car (good MAFS) to test mine

Thanks in advance for the timely reply!