themayor500

My fuel pump went out about 3 weeks ago in my 1984 Gsl se, i replaced it with a Bosch pump and havent had any problems with it(except its load as hell). This week after driving my car about 10 miles on the way to work, i let it sit for about 3 hours and when i got in it wouldnt start.

It turned out to be horribly flooded, worse than i had ever seen. I unflooded it and drove it around the block, shut it off and it started up no problem. I took the car out to eat, it sat for about an hour and it was flooded again, not quite as bad this time. I took it into work today(i work in a shop.) when i got there i checked my fuel pressure, and coolant temp sensor, and the checked out fine, i then pulled the fuel rail off to take a look at the injectors, they were dry, i let the fuel pump run for 10 mins while monitoring the injectors, not so much as a drop leaked.

Does anyone have any other idea on what may be causing my flooding problem?

Rx-7Doctor

iTrader: (13)

When you turn the key to the on position, do you hear the fuel pump come on before you start cranking the engine over?

Also it takes longer than 10 minutes for a leaky injector to show up. That's why you can shut the car off, go into the store and come back and it will start. But if you let it sit for hours then their is a issue.

themayor500

No the fuel pump does not come on when the key is in the on position, its not suppose to be. I jumped the fuel pump with the test lead and turned the key on to check for leaks under pressure. I also left the injectors sit all day on a dry cloth without the fuel pump on and no fuel accumulated.

Rx-7Doctor

iTrader: (13)

You are correct. The reason I always ask this question is if the fuel pump is coming on when you turn the key to the on position then you have a defective AFM.

How did you secure the injectors to the fuel rail to keep them from popping out of the rail under pressure?

themayor500

I wired them to the rail, as instructed in the mazda workshop manual.

Rx-7Doctor

iTrader: (13)

Make sure that the connector at the coolant temp sensor is tight.

Could be cranking compression is low. I would perform a compression test.
Also make sure that the engine is cranking well. If there is marginal engine compression and the engine is not turning fast enough it will also flood.

Flooding on the SE is caused by one or more of the following.

Leaking injector(s)
Faulty AFM.
Faulty coolant temp sensor or loose connector at sensor.
Low engine compression (seals down to limits)
Slower than normal cranking speed with starting engine.
Faulty leading ignition (ignitor intermittently working) could be due to loose connector at ignitor or just failing ignitor.

themayor500

I know the causes, and test for each of them, My ignitors are new, coolant temp sensor in good working order, compression is fine, injectors do not leak, AFM is working. Im stumped on this one.

mazdaverx713b

iTrader: (91)

if all of that is in order then you should not have any flooding issues. i would suspect that the injectors are leaking. www.witchhunter.com. best place around for injector servicing!

MadDuck

I found this thread after search on similar problem with my GSL-SE.

I'm wondering if my problem is the leaky injectors. My car will fire like a champ, instantly, in AM, to go to work. I'll drive home for lunch, car will sit for 1 hour, go out and I have to crank it for a minute to get it to fire. Now, just within last week, when I leave work for the day (car sits from 2 pm to 5 pm) the car has difficulty starting. Smells heavily of fuel when it fires... but I wasn't sure that was just from cranking it for a minute?

Anyways, the fuel evaporation over night sound like it might explain why it fires so well in the morning after sitting over night.


Let me know if anybody reads anything different here.

I have an LED on the ECU mounted in the glove box, so I am going to check for any codes while starting also. In case the AFM is throwing a code.

Best regards,
Jon K
Ann Arbor Michigan

themayor500

I never really found out what caused my flooding problem, as i said before everything that seemed to be a possible cause checked out fine. I took the intake off and did a check of the injectors. When i put the whole thing back together it seemed to have solved the problem. your best bet is to check all the things the doc listed. AFM, injectors, pressure regulator, and the coolant temp sensor.