Mazda MX-6 Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #1 ·
One bad thing after another. I was just driving the probe around, got to school, parked. When i came back from class i got about two block and it died at an intersection. Was able to start, barely kept it from dying and drove to a parkinglot.

Now when I try to start. It will turn on, rev up to about 1k and sputter and die. Some times i can get it to stay revving with my foot on accelerator, but as soon as i let do it drops back down and dies.

what do you think it is, a vacume hose? tb boot? I have no idea, its too dark now to look. But i do hear like a whistle type noise when i am trying to start and pumping the accelerator.

please tell me it is something simple
 

·
Registered
Joined
·
3,432 Posts
TiZBaD99 said:

Now when I try to start. It will turn on, rev up to about 1k and sputter and die. Some times i can get it to stay revving with my foot on accelerator, but as soon as i let do it drops back down and dies.
what do you think it is, a vacume hose? tb boot?
please tell me it is something simple


Simple.......probably the TB boot or a V-hose, as you mentioned.
Classic symptons, easy solutions !
 

·
Premium Member
Joined
·
4,971 Posts
FlySwat said:
Also check to make sure your VAF is plugged in.
I've driven my car 20 miles with the VAF unplugged. The car will idle and drive fine. It just has accelleration problems and shoots flames if you have no muffler.
 
G

·
Panther37 said:
The car will idle and drive fine.

It just has accelleration problems and shoots flames if you have no muffler.
I think you just proved my point, Matt.

I drove mine home with the VAF unplugged because I was afraid it would die if I stopped and I didn't know it was just the VAF. The car barely ran at at intersections, and ran super rich so I couldn't rev it over 3k.
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #7 ·
ok so i checked the vaccum lines and the tb boot, no probs with those. Then i unplugged the vaf and it worked. Do you think the vaf is bad? it would almost idle ok without the vaf

also i smell a lot of gas when i try to start it, what could cause that?
 
G

·
TiZBaD99 said:
ok so i checked the vaccum lines and the tb boot, no probs with those. Then i unplugged the vaf and it worked. Do you think the vaf is bad? it would almost idle ok without the vaf

also i smell a lot of gas when i try to start it, what could cause that?
Take your TB boot off and flex it around to look for cracks, a mere surface inspection is not suffecient.

If no cracks are found, swap the VAF from your mx-6 into it. They use the same VAF.
 

·
Registered
Joined
·
1,397 Posts
TiZBaD99 said:

also i smell a lot of gas when i try to start it, what could cause that?
That is from you cranking it a lot and it not starting. The fuel is building up in the cylinders and not burning so it smells very strongly.
 

·
Registered
Joined
·
3,432 Posts
Boot 'n vac.....

FlySwat said:
If no cracks are found, swap the VAF from your mx-6 into it. They use the same VAF.

Swat's right on, take a closer look at this stuff, as sometimes it's not always noticeably apparent.
The gas smell could be due to the VAF being disconnected, as it helps control the fuel pump.
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #11 ·
Hmm i thought the f2t used a maf compared to a vaf on f2. I guess its the fe3 that uses the mass sensor. Ok i will try to swap the vaf and then see if it works.

But what do you guys think about the EGR? could it be bad? would a faulty EGR cause my symptoms.

I will also disconnect the tb boot and take a better look at it by bending it. Am i correct to assume that most of the v-hoses are located to the rear of the engine? Are there any that I could have missed.
 
G

·
Re: Boot 'n vac.....

johniebgoode said:
Swat's right on, take a closer look at this stuff, as sometimes it's not always noticeably apparent.
The gas smell could be due to the VAF being disconnected, as it helps control the fuel pump.
The car goes into "Safety" mode with the VAF disconnected/malfunctioning, and runs extremely rich. Which is why it barely idles, and has no power above 3k rpm. This is also why you can smell gas, as a large portion of it goes through the combustion cycle unburnt.

Tizda, if you need, I can post how to check your VAF using a multimeter.

Another line to check is the vacuum line that runs to your Bypass valve.
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #13 ·
Flyswat, if you could post what voltages i should be reading off the vaf, that would be great. I recently "aquired" a multimeter because i wanted to check an 02 sensor. I havnt yet had the chance to swap vaf, as it is cold as a biotch outside and there are gale force winds right now.
 
G

·
Without unplugging the VAF, peel back the rubber insulator and check the voltages:

Starting from left:

Pin 1: ~12v
Pin 4: ~12v
Pin 5: 6 ~ 10v
Pin 6: 0.7-2.7v

Now, unplug the VAF, switch your meter to Impendence mode, and push the flapper door all the way open:

Pin 3 to Pin 6 resistance should be less than 400 ohms.
Pin 2 to Pin 1 should be continuety.

Final Check with the flapper door shut:

Pin 3 to Pin 6: Resistance should be more than 20.
Pin 3 to Pin 5: Resistance should be between 100 and 300.
Pin 3 to Pin 4: Resistance should be between 200 and 400.
Pin 2 to Pin 1: Should be continuety.

If any of these read out of spec, replace the VAF.
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #15 ·
ok guys, i would like to thank everyone, and especially flyswat for providing me with the correct specs for the vaf. Unfortunately i have checked everything that has been mentioned, tb boot, v-hoses, and vaf. Yet my problem still remains, does anyone have any more suggestions.

I am so depressed, i just got the tranny rebuilt on this car for a hefty price, can you believe that i had it for 5 hours before it died on me. I am at the point where i have no money left, and am desperate. My mechanic even helped me out for free and took a look at all the v-hoses and some other stuff, right now the car is at his place, and he hasnt charged me anything yet. He tells me that he is going to take a look at a bunch of sensors, I told him that i already tried to pull the codes and got nothing. Since he hasnt charged me anything, i think he hasnt taken a thorough look. Should i ask him to go ahead and put in some work into my car? He charges a lot $90/hr labor. I do trust him and feel that he will fix it, but like i said i am at the end of the rope in terms of money, realisticly I have about $250 left (all from working tonight and last night + some left overs).

So any more help would be deeply appreciated.

thanks in advance (hopefully)
 

·
Registered
Joined
·
1,626 Posts
When VAF gets partialy diconnected ,engine light comes on and car runs for few moments and dies.
Did your check engine come on before it died?? does it only shut off when your car is cold.
If not(no check engine light), this could be bad throttle positon sensor or whichever( there are 2 sensors radiator hose housing) one lets the engine warm up before driving.
those sensors are not too expensive.
If this is the case , even Diag. Computer would not tell you what's wrong .. maybe yes ... sometimes they screw up too:p . so dont flame me if I'm wrong....;)
 
G

·
iggypop said:
When VAF gets partialy diconnected ,engine light comes on and car runs for few moments and dies.
Did your check engine come on before it died?? does it only shut off when your car is cold.
If not(no check engine light), this could be bad throttle positon sensor or whichever( there are 2 sensors radiator hose housing) one lets the engine warm up before driving.
those sensors are not too expensive.
If this is the case , even Diag. Computer would not tell you what's wrong .. maybe yes ... sometimes they screw up too:p . so dont flame me if I'm wrong....;)
Throttle position sensor is located next to the throttle wheel on the throttle body. Not on the thermostat housing.

Your thinking of the coolant temperature sensor, and the radiator fan thermoswitch.

Tizda, I know how you feel about not having the finances to properly diagnose your car. I feel the next step is to remove your intercooler and have it pressure tested. You could possibly have a cracked/leaking end tank.
 
1 - 17 of 17 Posts
Top