RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   starts when i pour gas down the intake but then dies (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/starts-when-i-pour-gas-down-intake-but-then-dies-743186/)

ITSWILL 03-28-08 03:55 PM

starts when i pour gas down the intake but then dies
 
all the fuses are good

i tried switching the feed and return line around just to make sure that wasn't it but that didn't work.

right now i have the return line closer to the firewall.

when i crank it fuel comes pouring out the feed line ( when unhooked)

i got it to stay running for a while a couple months ago but had to prime it then too.

I would appreciate any help i can get as i just broke the tranny in my truck and i need the rx7 to get to work and school.

I know i have a couple threads here but there a a bunch of non major problems with the car that keep leading me astray.

xfeastonarsex 03-28-08 04:01 PM

Are the injectors working? Sounds like fuel is being pumped but it isnt reaching the combustion chamber.

ITSWILL 03-28-08 04:08 PM

im not sure if they are working.

but i did get it to keep running like two months ago, so im not sure.

Is there an easy way to test them with out taking the intake manifold apart?

I have heard that you can hear them but im not sure what im listening for?

Sojin 03-28-08 04:23 PM

yes u can hear them pulse but that just tells u that its getting trigger but still fuel might not come out it might be clogged but that might be a food start

ITSWILL 03-28-08 04:38 PM

ok so how do i check the injectors?

and do i have my fuel lines right?

ITSWILL 03-28-08 06:02 PM

ok i primed it a couple more times and it started and kept running is guess i got the line in the right position.

Only problem is when i shut it off it will not start back up on its own.

any ideas?

HAILERS 03-28-08 06:32 PM

Low compression. Badly leaking injectors. Stuff. OR the water thermo sensor is disconnected. IF that were so, the engine would be hard to Start cold, but when the engine is HOT, it would start in a normal fashion.

Remember the sensor signal defaults to 180* and that is the reason it would start if the engine was HOT even if the sensor was disconnected. It's COLD starts that are difficult when that sensor is disconnected.

TehMonkay 03-28-08 06:34 PM

How is the filter? Is the pump getting enough power? Maybe the fuel pump is dying? Have you run out of gas recently?

ITSWILL 03-28-08 06:41 PM

It was supposedly rebuilt recently but I will check the compression tomorrow.

I haven't ran it enough for it to be completely warmed up so i will try that too.

Where would that water thermo sensor be? And if it is bad is there a way i can test it.

And how can i tell if an injector is leaking?

I should also mention that it has larger injectors installed by the previous owner so im not sure what exactly they are, and it has an safc as well. But would any of that have any affect on it starting?

ITSWILL 03-28-08 06:43 PM

i just filled up 2 liter with gas from the feed line in about 30 seconds by pushing on the afm. (I would imagine it is flowing properly.)

TehMonkay 03-28-08 06:52 PM

Well that whould mean you probably have a walbro. Is it T2? Does it have a T2 secondary rail with the T2 fpr? Are you getting good voltage to the pump?

ITSWILL 03-28-08 09:33 PM

the car is a TII so i would imagine the secondary rail and pressure reg are stock, but i wouldn't be surprised if the fuel pump is a walbro as the previous owner made quite a few modifications.

ITSWILL 03-29-08 09:31 PM

ok i did the compression test and i got 70psi on one rotor and 75 on the other

i tried to listen to the injectors while starting and i heard nothing.

someone told me that the primary injectors run from idle on or from idle to 3000rpm or something and that the secondary injectors kick on at around 3000rpm

is it possible that when i pour gas in the engine to get it to start, the primaries aren't working but when it fires on the gas i pour in and it gets to 3000 rpm the secondary injectors fire and keep the car running?

Nitrometano 03-29-08 09:53 PM

Use a multimeter in the AC position. Put each probe on each injector connector (ECU wiring side) .Then when you start the engine the meter shoud read alternative voltage. Also, when you put the ignition swith in ON position, one of the injector cables shoul read 12 volts. To get that reading, put the meter on the DC setting, put the black probe on a good ground and use the red one to find the injector cable that have the 12v. If you get that readings, your problem is in another part. You can check also the fuel pump wiring. There is one cable that needs to have 12v and the other one is ground. If you dont get that voltage, maybe you have problems with the fuel pump wiring or relay. If that is the problem, you can use and install an external relay just by passing the original one.

Also you can chek the fuel pump pressure at the return hose. You need a fuel pressure gauge and the fuel press needs to be between 37 and 39 psi.

I notice that your rotors have a compression ratio about 70 psi There are supouse to have 90 psi at minimun. Just try to squirt a bit of engine oil thru the spark plugs. This will help to seal the gap between the apex seals and the housings. This will rise your compression necessary to start your engine. If your engine start, you will have compression problems.

Just try this tests.


All times are GMT -5. The time now is 05:28 AM.


© 2024 MH Sub I, LLC dba Internet Brands