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Does this look like a fouled plug

Old 09-26-15, 12:41 AM
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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; 09-26-15 at 05:11 PM.
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Old 09-26-15, 12:47 AM
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Definitely looks fouled .

Last edited by heynoman; 09-26-15 at 12:51 AM.
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Old 09-26-15, 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; 09-26-15 at 02:09 AM.
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Old 09-26-15, 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 09-26-15, 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 09-26-15, 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 09-26-15, 04:56 PM
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Originally Posted by lduley View Post
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 09-26-15, 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 09-26-15, 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 09-26-15, 08:33 PM
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Originally Posted by lduley View Post
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 09-26-15, 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 09-27-15, 12:26 AM
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Originally Posted by lduley View Post
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 09-27-15, 02:48 AM
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Nothing wrong with that at all.
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Old 09-27-15, 08:14 AM
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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 09-27-15, 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; 09-27-15 at 08:54 AM.
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Old 09-27-15, 04:20 PM
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Originally Posted by Sgtblue View Post
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 09-28-15, 04:14 AM
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TX

Originally Posted by Aramir View Post
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 09-28-15, 04:27 AM
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Originally Posted by Red-Dragon_Akuma View Post
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 09-29-15, 05:08 AM
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Originally Posted by Aramir View Post
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 09-29-15, 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; 09-29-15 at 08:45 AM.
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Old 09-30-15, 06:42 AM
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TX Okay

Originally Posted by Aramir View Post
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 10-01-15, 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 10-02-15, 06:22 AM
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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 10-10-15, 02:49 AM
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Originally Posted by lduley View Post
If your going thru plugs that fast, you have another issue
^What he said.
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Old 10-18-15, 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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