Bad gas?

 

sounds like a bad fuel pump to me, and im usually right.


why? because i can hear alternations between firing on 1 rotor, 2 rotors and 0 rotors in the matter of only a few second span, which is a sign of low or no fuel pressure.

the engine would always wheeze if it was bad gas.

 

alright rotaryevolution this is the pump im going to get. the stock OEM from mazdatrix is 350.00 bucks and this one is about half that

Aeromotive 340 Stealth Fuel Pump

ive read reviews of it elsewhere. Can you recommend anything else?

 

For an NA, a 340 is going to be overkill a Walbro GCA 359 is an OEM replacement, you should be able to find one for under $150 I would check rock auto also

 

He's out've the country, so his options are limited somewhat

 

i'd double check the fuel pressure before dropping money on a new pump, still have to be sure.

the stealth is overkill but it should work fine, doesn't cause as bad of an overpressurization condition as the walbro pumps do.

 

Im woth RE on this one. You should try getting some starting fluid to see if it runs better at start. As you can tell it has spark and compression(iduley!!), because it runs a little.

Dont gotta jump the gun with a rebuild everytime it wont turn on

 

Update: Fuel pump has been purchased and is going in today. Thanks everyone for the continued support. I will update on whether or not it starts.

If I do get starting fluid, where do I spray it? Into the intake?

 

Just enough fuel to start it up. I'm thinking fuel pump as well.

 

I replaced the fuel pump and nothing has changed. When I started it the first time after changing the pump, it idled for longer than usual. What im thinking is its either a vacuum leak or a dirty fuel tank. the plastic on the floater was discolored and there is visible rust on the lower part of the pump cradle.

Next step will be to find a friend to compression test the engine.

im going to hook the fog machine up first and check for vacuum leaks.

QUESTION: where do I spray the starting fluid?

 

An easy place to spray starting fluid is unplug a vacuum port near the dynamic chamber such as the large diameter one for the AWS valve. Also maybe try funneling some engine oil into the rotor housings via on of the vacuum ports behind the throttle body (the ones for cruise control etc) to raise compression. Maybe fuel washed away the oil film inside the engine and its down on compression.

 

New developments:

-unplugged MAF Car stayed on for a while revved up to +3k and held idle with foot slightly depressed.

-Removed intake box and sprayed carb cleaner into the intake. Car held idle normally while the spray was active (MAF was plugged in during this).

-Now im thinking its a fuel starvation issue coming from the fuel pump hanger. The point where the cradle meets the pump is pretty old and the gasket isn't creating a tight seal. So this is maybe causing loss of fuel pressure?

Thanks guys, were so close. 0_0

 

With everything plugged in check the Brown/White wire of the boost sensor w/key to on to verify that the voltage is 5 volts. If it is not (like close to 0 volts) then the AFM could be shorting out the part of the ECU responsible for the injectors.

 

Most definitely check for vacuum leaks before dropping any more money on expensive mechanical parts. I had experienced very similar stalling once and assumed it was flooded, but it really just a loose hose.

Blow some smoke through it

 

Fuel pump mod S4 style

So I modded the fuel pump to bypass the area where the pump and hanger meet with some fuel hose. that didn't fix the issue but who knows, it could have been contributing to the problem. Im definitely leaning towards the AFM. I will test it today guys. Sorry I take long to do these tests but I get off work super late and usually just sleep until the next day and do it all over again.

more vids:

 

Startup VID

 

I'm kind of nervous about this but as it was idling I sprayed carb cleaner around the engine bay to find vacuum leaks and there was no change in idle behavior. I have all the gear for a smoke check and I will also do that today. thanks everyone. thanks satch. thanks for all the help.

 

vaccum system is tight. No leaks. sprayed carb cleaner around at idle with no changes and i hooked up a fog machine to the brake booster line. No smoke leaked out of anywhere except the small holes in the duct tape at the intake

 

Post #38 (takes but a minute to do).

 

Heres what i got satch. Looks like you were right.

 

Is that w/key to on? If so, then unplug the AFM and retest the same wire and see if it registers 5 volts. And make sure that Brown wire has the White stripe to it (Brown/Black is the ground wire).

 

The key was on during both tests and voltagewas at 5 voltz at the brown/white wire with AFM unplugged.

 

Then your AFM is the problem.

 

Great. Ill order the part, install and post results. I appreciate the help leading up to this point. In the meantime i am going attempt to* to disassemble and repair the faulty AFM.

 

Buying a used one will do you better than purchasing a remanufactured one, as you would be hard pressed to recall an instance where a person was happy with the reman.