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Engine Occasional misfires normal for a HCI?

  • Thread starter Thread starter AnthonyA1234
  • Start date Start date Jan 26, 2023
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AnthonyA1234

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#41
  • Jan 30, 2023
  • #41
AeroCoupe said:
Have never used a gasket on the front or rear of the lower intake. Good bead of RTV and let it skin up for about 30 min then install the intake.

If the EGR leaks smoke then the engine can suck air into it the same route which is unmetered are going into the intake.
Click to expand...
Alright sounds good so that lower intake seal will be the next project.

Dang man I don’t know I put 4 different brand new egrs and every one of them leaked smoke. Is there anything I could spray on the egr while it’s running to see if it changes the idle?
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#42
  • Jan 30, 2023
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I could very well be wrong but it doesn’t make sense. Where did the smoke come from on the EGR?
 

AnthonyA1234

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#43
  • Jan 30, 2023
  • #43
It’s hard to tell but I believe it’s around the metal shaft inside the egr where it goes into that red bladder
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
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#44
  • Jan 30, 2023
  • #44
Searched and found where Mustang5L5 had a really good thought on why an EGR will always leak smoke during a smoke test. I’m going to noodle around on this more tomorrow.
 

AnthonyA1234

5 Year Member
Aug 17, 2020
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Jan 30, 2023
#45
  • Jan 30, 2023
  • #45
AeroCoupe said:
Searched and found where Mustang5L5 had a really good thought on why an EGR will always leak smoke during a smoke test. I’m going to noodle around on this more tomorrow.
Click to expand...
Yea I’m telling you you’ll find a bunch of people online saying smoke comes out of their egr on smoke tests and there’s always some that say it’s normal and some that say it’s not. I had a good month where I’d be changing egrs and doing smoke tests all the time. The smell of that baby oil smoke is the worst!

What do you guys recommend for spraying on a running engine to see if it changes the idle for finding vac leaks. I’d be spraying it on the egr and around the rear lower intake seal.
 

General karthief

wonder how much it would cost to ship you a pair
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#46
  • Jan 30, 2023
  • #46
I've used brake cleaner in the past, I think the new stuff is not flammable, I've also used WD40, I just rinse the engine off after it cools down.
 
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AnthonyA1234

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#47
  • Feb 1, 2023
  • #47
Cars been running really good lately. It did misfire that first night I took it out after changing the plugs but it hasn’t done it again.

One thing I’m wondering is, being that I had some oil on the plugs, would I benefit from adding in a catch can to beef up my Pcv system?
 

General karthief

wonder how much it would cost to ship you a pair
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#48
  • Feb 1, 2023
  • #48
No catch can. Don't need it.
If you have a rich condition I would check if the fuel pressure regulator is bad by pulling the vac line and smelling it for fuel, if you smell fuel in the vac line the fpr is bad.
 
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AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
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Feb 1, 2023
#49
  • Feb 1, 2023
  • #49
This is just me but I would pull the plugs and look at them. I know you just put them in but it doesn’t take long for them to tell a story.
 
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