Bone stock car knocking on load
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Eff Dee Three Ess
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Bone stock car knocking on load
Hi everyone. I bought a 93 LHD touring model. When I bought it I noticed it knocked when I put my foot into it. I figured it was the old fuel and forgot abbot it.
I've since run 2 tanks of 91 through it and it still does it. I don't think it's the fuel.
And I can't adjust timing on this engine. SDI what an I left with?
Fuel filter? Fuel screen if any?
Not sure what wise it could be. The engine is 5000km old, built at Mazda. Boost pattern is correct. Runs perfectly side from a small stumble when accelerating lightly around 2000 rpm.
Should I check my tps? Anyone know the readings I need offhand?
I've since run 2 tanks of 91 through it and it still does it. I don't think it's the fuel.
And I can't adjust timing on this engine. SDI what an I left with?
Fuel filter? Fuel screen if any?
Not sure what wise it could be. The engine is 5000km old, built at Mazda. Boost pattern is correct. Runs perfectly side from a small stumble when accelerating lightly around 2000 rpm.
Should I check my tps? Anyone know the readings I need offhand?
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Eff Dee Three Ess
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It's definitely knocking, the car runs perfectly, all wires are giving spark. the plugs are 5000km old.
you can hear it clearly through the firewall. I dont put my foot into it anymore because of this. does anyone have any insight?
you can hear it clearly through the firewall. I dont put my foot into it anymore because of this. does anyone have any insight?
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Checked TPS, sitting within spec. I'm officially lost now.
(green wire with red strip) Closed throttle +V range is 0.75 to 1.25. Fully open throttle +V range is 4.8 to 5.0.
(black wire with green strip) Closed throttle +V range is 0.1 to 0.7. Fully open throttle +v range is 4.2 to 4.6.
(green wire with red strip) Closed throttle +V range is 0.75 to 1.25. Fully open throttle +V range is 4.8 to 5.0.
(black wire with green strip) Closed throttle +V range is 0.1 to 0.7. Fully open throttle +v range is 4.2 to 4.6.
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every time i've seen a stock FD knock, its been a bad plug wire. not sure why that makes them knock, but it does.
the wires need to be the correct type, the resistance spec should be in the FSM. you also may wanna make sure the wires are on the coils all the way, people screw this up all the time/crap wires fall off.
next step is to make sure it has the correct plugs in it.
if it still does it, you might wanna check that the fuel pressure regulator vacuum line is hooked up correctly, and then maybe you need fuel filters. there is a sock in the tank
the wires need to be the correct type, the resistance spec should be in the FSM. you also may wanna make sure the wires are on the coils all the way, people screw this up all the time/crap wires fall off.
next step is to make sure it has the correct plugs in it.
if it still does it, you might wanna check that the fuel pressure regulator vacuum line is hooked up correctly, and then maybe you need fuel filters. there is a sock in the tank
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Eff Dee Three Ess
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Very weird that a lack of spark would cause knock.
So i guess i should add plug wires and plugs to my list.
- Fuel filter
- Plug wires
- Platinum plugs, heat range 7 leading, 9 trailing.
So i guess i should add plug wires and plugs to my list.
- Fuel filter
- Plug wires
- Platinum plugs, heat range 7 leading, 9 trailing.
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it might be a cross fire, for sure i've seen more than one wire set installed badly...
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Eff Dee Three Ess
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That's an interesting idea. the engine was replaced 5000km ago at the mazda dealership in Vancouver. It didn't cross my mind because I assumed Mazda would know how to do something as simple as plug wires, but i'll have a look at that as well when i do the plugs.
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ok, so i took a look at the plugs and wires today. Everything looks like it was replaced when the new engine was installed 5000km ago. The plugs are a nice dark brown, looks like good even combustion
The plugs are in the right places. BUR7EQP Leading (bottom). and BUR9EQP trailing (top). Plug wires are going in the right places as per the attached picture.
All 4 wires show good continuity, and almost exactly the same resistance.
The plugs are in the right places. BUR7EQP Leading (bottom). and BUR9EQP trailing (top). Plug wires are going in the right places as per the attached picture.
All 4 wires show good continuity, and almost exactly the same resistance.
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ok, so i took a look at the plugs and wires today. Everything looks like it was replaced when the new engine was installed 5000km ago. The plugs are a nice dark brown, looks like good even combustion
The plugs are in the right places. BUR7EQP Leading (bottom). and BUR9EQP trailing (top). Plug wires are going in the right places as per the attached picture.
All 4 wires show good continuity, and almost exactly the same resistance.
The plugs are in the right places. BUR7EQP Leading (bottom). and BUR9EQP trailing (top). Plug wires are going in the right places as per the attached picture.
All 4 wires show good continuity, and almost exactly the same resistance.
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Eff Dee Three Ess
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Tried filling up with 94 octane from an empty tank, still some knock at wot.
this thing is starting to make me upset. would be a shame to blow up a brand new engine.
this thing is starting to make me upset. would be a shame to blow up a brand new engine.
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#21
"Elusive, not deceptive!”
The stock plugs run a lot of gap. About .060" if I remember right.
I found that a HKS Twinpower was the best addition to a nearly stock (and up to 550 hp) engine.
It is easy for the spark to blow out with boost and a wide gap.
Could the pick-up coils have their plugs reversed?
You might try to decarbonize the rotors... maybe you have a buildup of carbon.
Chevron Techron is a great injector cleaner but also cleans internal carbon buildup.
Also, do people still use Seafoam as a cleaner?
Some thoughts,
Barry
I found that a HKS Twinpower was the best addition to a nearly stock (and up to 550 hp) engine.
It is easy for the spark to blow out with boost and a wide gap.
Could the pick-up coils have their plugs reversed?
You might try to decarbonize the rotors... maybe you have a buildup of carbon.
Chevron Techron is a great injector cleaner but also cleans internal carbon buildup.
Also, do people still use Seafoam as a cleaner?
Some thoughts,
Barry
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I thought it was detonation and looked at everything I could including performing a crude version of an injector pressure drop test. Finally got to the point I concluded the running of the car was fine. After a while the disk started rattling at idle which made the diagnosis easy.
Anyway, rattling clutch disk a possibility to consider.