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Does this look like a fouled plug

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Old Sep 26, 2015 | 12:41 AM
  #1  
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Does this look like a fouled plug

Having issue with car not starting. Car died out while i was driving, got it towed back to my house about two months ago. Car will crank and i can smell petrol but wont fire so i thought it might be the spark plugs. What do you guys make of these?

Edit: The background to the car breaking down is that i was out late on a friday night for some spirited driving, started it up to drive to work on the saturday morning and drove mint. When i went to drive home, she started up fine and about halfway back i had to slam on my breaks for some old lady. The abs definitely came on and that was the first time during my ownership they have (for what its worth).

Literally 30 seconds after that my car just cut out on me while i was driving, I started it back up and it drove fine for another 10 minutes when i got to an intersection and it cut out again, only this time it wouldnt fire. It would crank, and if i mashed the gas it might catch and splutter a tiny bit but really i was getting nothing.

Fast forward two months and here i am, please help me guys im desperate to get my car back on the road.





Last edited by Aramir; Sep 26, 2015 at 05:11 PM.
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Old Sep 26, 2015 | 12:47 AM
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Definitely looks fouled .

Last edited by heynoman; Sep 26, 2015 at 12:51 AM.
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Old Sep 26, 2015 | 01:36 AM
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So should i replace them, or can i try repair them and brush the crap off?
Also are these the best plugs i could be using, theyre BUR9EQ top and BUR7EQ BOTTOM

These are the plugs, im assuming they are the factory mazda ones? if so i should probably replace them since theyd be about 22 years old right

Last edited by Aramir; Sep 26, 2015 at 02:09 AM.
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Old Sep 26, 2015 | 05:00 AM
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You can go ahead and clean them up with a light bristle or brass brush and starting fluid or gasoline . But they are probably not the reason your car died on you.
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Old Sep 26, 2015 | 08:00 AM
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^Agreed. The one picture that shows the end of the plug is out of focus, but it doesn't appear to be all that bad.
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Old Sep 26, 2015 | 02:55 PM
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No, i'm gonna say since you have the plugs out, compression test it, probably won't be good readings
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Old Sep 26, 2015 | 04:56 PM
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Originally Posted by lduley
No, i'm gonna say since you have the plugs out, compression test it, probably won't be good readings
Ok, ive put up a post in my local rotary group to borrow a compression tester. What other tests should i do in the meantime, or in case my compression comes up okay?

The background to the car breaking down is that i was out late on a friday night for some spirited driving, started it up to drive to work on the saturday morning and drove mint. When i went to drive home, she started up fine and about halfway back i had to slam on my breaks for some old lady. The abs definitely came on and that was the first time during my ownership they have (for what its worth).

Literally 30 seconds after that my car just cut out on me while i was driving, I started it back up and it drove fine for another 10 minutes when i got to an intersection and it cut out again, only this time it wouldnt fire. It would crank, and if i mashed the gas it might catch and splutter a tiny bit but really i was getting nothing.

Fast forward two months and here i am, please help me guys im desperate to get my car back on the road.
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Old Sep 26, 2015 | 07:10 PM
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Update: Have compression tested the car, was getting 35 psi bounces on both front and back rotors with the release valve pressed down, and showing a max of 87 psi front and 90 rear.

What do you guys make of these results?
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Old Sep 26, 2015 | 08:19 PM
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Originally Posted by Aramir
Update: Have compression tested the car, was getting 35 psi bounces on both front and back rotors with the release valve pressed down, and showing a max of 87 psi front and 90 rear.

What do you guys make of these results?
Wait, you got 35 psi bounces but 80-90 maximum? Thats a big leap for cumulative compression

Either way, the bounces are what really matter, shes shot
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Old Sep 26, 2015 | 08:33 PM
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Originally Posted by lduley
Wait, you got 35 psi bounces but 80-90 maximum? Thats a big leap for cumulative compression

Either way, the bounces are what really matter, shes shot
The bounces were with release valve depressed ie not cumulative which is what this thread https://www.rx7club.com/1st-gen-arch...tester-597883/ says is what youre after?
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Old Sep 26, 2015 | 09:37 PM
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Ok so we're not on the same page, were did the 85-90psi come from?
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Old Sep 27, 2015 | 12:26 AM
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Originally Posted by lduley
Ok so we're not on the same page, were did the 85-90psi come from?
85-90 is the cumulative psi
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Old Sep 27, 2015 | 02:48 AM
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Nothing wrong with that at all.
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Old Sep 27, 2015 | 08:14 AM
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roTAR needz fundZ
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Originally Posted by Aramir
85-90 is the cumulative psi
Didn't i say that?

Still, your bounces are really low, even if you do get it to start, it probably won't run worth a crap, and probably won't start back up hot
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Old Sep 27, 2015 | 08:50 AM
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Compression seems a little low, but from your account it sounded like it hot-started OK. If you're getting fuel, I think I might check ignition...coils to start.

Last edited by Sgtblue; Sep 27, 2015 at 08:54 AM.
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Old Sep 27, 2015 | 04:20 PM
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Originally Posted by Sgtblue
Compression seems a little low, but from your account it sounded like it hot-started OK. If you're getting fuel, I think I might check ignition...coils to start.
Do you have a link to a decent guide on how to?
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Old Sep 28, 2015 | 04:14 AM
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Originally Posted by Aramir
Do you have a link to a decent guide on how to?
Did you ever get the car running? what was the problem after all ?
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Old Sep 28, 2015 | 04:27 AM
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Originally Posted by Red-Dragon_Akuma
Did you ever get the car running? what was the problem after all ?
Nah mate, only really have time to work on the car in the weekends Im hoping this weekend is the one, ill deff report back on what the issue was though.
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Old Sep 29, 2015 | 05:08 AM
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Originally Posted by Aramir
Do you have a link to a decent guide on how to?
Bench testing is set out in Factory Service Manual, page G-21.
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Old Sep 29, 2015 | 08:43 AM
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holding the release valve on the tester is the lame way of doing a compression test. remove the schraeder valve from the hose on the tester and don't touch the release valve on the gauge for a more accurate result.

35 is rather normal for the lame test though, so i doubt your engine is toast just yet.

i'd start by checking the fuses, EGI and engine in particular.

if you want any more advice you should probably list what model car you have.......

Last edited by RotaryEvolution; Sep 29, 2015 at 08:45 AM.
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Old Sep 30, 2015 | 06:42 AM
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Originally Posted by Aramir
Nah mate, only really have time to work on the car in the weekends Im hoping this weekend is the one, ill deff report back on what the issue was though.
Okay, hope you get it up and running again. I will be checking up on this tread to see if you ever got it on the road again mate. please keep us posted in any update or issues that you came across.
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Old Oct 1, 2015 | 05:49 PM
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You should get new plugs if anything regardless. Mines always get fouled and i have to changes them pretty often. The 1st time it happen to me i was car less for 3 weeks trying to figure out what was wrong. I put new spark plugs in.. the car started in the 1st try.
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Old Oct 2, 2015 | 06:22 AM
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roTAR needz fundZ
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Originally Posted by aeenox
You should get new plugs if anything regardless. Mines always get fouled and i have to changes them pretty often. The 1st time it happen to me i was car less for 3 weeks trying to figure out what was wrong. I put new spark plugs in.. the car started in the 1st try.
If your going thru plugs that fast, you have another issue
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Old Oct 10, 2015 | 02:49 AM
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Originally Posted by lduley
If your going thru plugs that fast, you have another issue
^What he said.
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Old Oct 18, 2015 | 02:39 AM
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Ok guys so today my car is officially back on the road.
What I found was that my fuel pump power feed was broken somewhere, I'm not sure where to be honest because I just ran a new 4mm cable straight from the battery (which I relocated to the boot) into the fuel pump, switched by a relay that is triggered from the ignition being switched on.

For those that are wondering, by passing 9v/12v two stage system and running constant 12v to the pump has next to no effect, car seems to run exactly the same as before.

Anyways, what I think my issues with the starting was, when I had the auto electrician around and he diagnosed the fuel pump problem, he ran a temporary feed to the pump and turned the car over. It started of course but he killed it after a second. This flooded the engine I'm guessing, as when I compression tested the car a heap of fuel vapour streamed out. As soon as the new spark plugs were I she fired right up
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