2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

car has some starting problem

Old Jan 26, 2008 | 06:16 PM
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car has some starting problem

Hello,

Just now I have encountered some problem trying to start my car.

I drove my car for around 20mins freeway, then parked for about 30mins and i had a hard time to start the engine.

i tried to start the engine as usual (clutch in, turn key), it turns but just failed to pick up and died off. Symptom is the rpm wouldn't go above 1k and then died for couple of times.

i then pressed the gas pedal and gave gas while turning and the engine finally fired up. (I did this step for 3 times before the engine fired up)
While driving there was no problem at all, idle is normal (about 800rpm)

Any thoughts? what is possibly causing the problem? could it be a bad fuelpump?

Thanks in advance.


ps: Car is a 88 turbo complete stock besides an aftermarket BOV. All spark plugs and plugs wire were changed 1k miles ago.
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Old Jan 26, 2008 | 06:57 PM
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Sounds like a flooded engine.
Possible Culprits are
1. Leaky Fuel Injectors
2. Low Compression
3. Both

Solutions
1. Get Leaky Injectors Sonically Cleaned.
2. Install a Fuel Cut Switch
3. Wait until motor is gone and rebuild.

Quick Fix
1. Pull the fuel fuse in the engine, crank a bit, replace fuse,start car
2. If 1 doesn't work a few times, push start
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Old Jan 26, 2008 | 08:06 PM
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^^ thanks. will look into it.

others if you have any inputs please feel free.
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Old Jan 26, 2008 | 08:15 PM
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Originally Posted by farberio
Sounds like a flooded engine.
Possible Culprits are
1. Leaky Fuel Injectors
2. Low Compression
3. Both

Solutions
1. Get Leaky Injectors Sonically Cleaned.
2. Install a Fuel Cut Switch
3. Wait until motor is gone and rebuild.

Quick Fix
1. Pull the fuel fuse in the engine, crank a bit, replace fuse,start car
2. If 1 doesn't work a few times, push start
but I thought fuel cut switch is for people who want to run higher boost? how does it solve flooding?

"This switch is mandatory for any modifications that will be increasing boost. The computer is pre-programmed for shut down of fuel to the rear rotor at a boost of 8.6 PSI. The fuel cut out switch tells the computer that the boost is lower than it actually is. " -> from mazdatrix fuel cut off switch desciption.

thanks
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Old Jan 26, 2008 | 08:53 PM
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Originally Posted by r33
but I thought fuel cut switch is for people who want to run higher boost? how does it solve flooding?

"This switch is mandatory for any modifications that will be increasing boost. The computer is pre-programmed for shut down of fuel to the rear rotor at a boost of 8.6 PSI. The fuel cut out switch tells the computer that the boost is lower than it actually is. " -> from mazdatrix fuel cut off switch desciption.

thanks
You are confusing a Fuel cut switch with the boost cut sensor.

Too much boost will cut the fuel to the engine. That is what the Mazdatrix part you are posting about does.... prevents the boost cut.

A fuel cut switch cuts the fuel pump when starting on engines that have poor compression.
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Old Jan 26, 2008 | 09:04 PM
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Originally Posted by Icemark
You are confusing a Fuel cut switch with the boost cut sensor.

Too much boost will cut the fuel to the engine. That is what the Mazdatrix part you are posting about does.... prevents the boost cut.

A fuel cut switch cuts the fuel pump when starting on engines that have poor compression.
thanks for clarifying. Where can i buy one of those Fuel cut switch? thanks
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Old Jan 26, 2008 | 09:57 PM
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From: bay area
Originally Posted by farberio
Sounds like a flooded engine.
Possible Culprits are
1. Leaky Fuel Injectors
2. Low Compression
3. Both

Solutions
1. Get Leaky Injectors Sonically Cleaned.
2. Install a Fuel Cut Switch
3. Wait until motor is gone and rebuild.

Quick Fix
1. Pull the fuel fuse in the engine, crank a bit, replace fuse,start car
2. If 1 doesn't work a few times, push start
Which fuse to pull? the EGI fuse??
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Old Jan 27, 2008 | 02:52 PM
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From: bay area
so where's fuel pump fuse? or i just simply pull EGI fuse if i want to cutoff power of fuelpump to deflood?

where can i get one of those fuel pump cutoff switch?

thanks
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Old Jan 27, 2008 | 03:22 PM
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1. You have to make your own cutoff switch. I think (although am not positive...search) that you rewire the fuel pump power line through a switch. Then you can mount that near the driver area.

2. I think its the EGI fuse, its called two different things in S4/S5 so I can't tell you for certain. I can tell you its none of the others that don't make any sense.
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Old Jan 28, 2008 | 01:04 PM
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Originally Posted by farberio
1. You have to make your own cutoff switch. I think (although am not positive...search) that you rewire the fuel pump power line through a switch. Then you can mount that near the driver area.

2. I think its the EGI fuse, its called two different things in S4/S5 so I can't tell you for certain. I can tell you its none of the others that don't make any sense.
Thanks for the info.

So basically with the "home made" switch what I want to do is to switch off the power to the fuel pump after I shutoff the engine to prevent any fuel leak?

Or I only switch off the fuel pump while I m having hardtime doing a hot start?

Sorry I m still learning, hence the question...........
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Old Jan 28, 2008 | 01:14 PM
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I had the same issues with my 87 i couldnt figure out the problem I installed a fuel cut switch. an nothing still the same only thing i didnt check were the injectors
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Old Jan 28, 2008 | 03:21 PM
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Originally Posted by r33
Thanks for the info.

So basically with the "home made" switch what I want to do is to switch off the power to the fuel pump after I shutoff the engine to prevent any fuel leak?

Or I only switch off the fuel pump while I m having hardtime doing a hot start?

Sorry I m still learning, hence the question...........
We all have to start somewhere, but believe me most people are not as helpful with new people because of the endless amounts of knowledge on the boards. The search tool is your best friend. That and lurking the threads, read every problem post and sooner or later you learn little by little.

You will want to shutoff your car by cutting the fuel pump and then turning the key. The idea is to use up all the fuel that would have leaked into the motor.
You can do this at all times to turn off the car, it then doubles as an anti-theft device.
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Old Jan 28, 2008 | 03:23 PM
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Originally Posted by zilubak
I had the same issues with my 87 i couldnt figure out the problem I installed a fuel cut switch. an nothing still the same only thing i didnt check were the injectors
Remember that low compression, according to AaronCake, increases a flooding chance by 1000x, eventually this will cancel out your fuel cut off switch. Check your compression, if that checks out then it's probably your injectors.
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