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Exhaust EGR and SMOG Systems - KOEO code 34

  • Thread starter Thread starter johnny21
  • Start date Start date Nov 16, 2020
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    egr issues smog
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7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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Kearney, NE
May 1, 2022
#21
  • May 1, 2022
  • #21
Dan02gt said:
Of that I have no doubt. People just start ripping mess out and cause tons of problems.

The EGR and air injection system are the source of lots of issues with these cars. The EGR valve has a tendency to get stuck semi open due to carbon, causing codes and the car to run like crap. The diaphragm cracks and causes vacuum leaks. The bundle of vacuum lines for the TAB/TAD solenoids have a tendency to break and leak causing more vacuum leaks and running like crap. The air pump has a tendency to lock up.

I my opinion it’s nothing but a headache. Mine is completely removed with the vapor tank and purge valve being the only thing left. I did it right by property removing everything. I now only have a couple of vacuum lines and my passenger strut tower is super clean.

I do however have a Quarterhorse with a custom tune that has the EGR and thermactor systems disabled.

If you’re going to fix it you have to do it like you did and fix it right. Working correctly it’s not a problem and really doesn’t rob any horsepower.
Click to expand...
I do not have access to a Quarterhorse, but I like the idle lope.
I have not had problems with this air pump. But my 79 flung the Air pump pulley across the parking lot and it rolled onto the fairway when it was parked. No unusual noise when I drove it there, but everything came off the shaft.
 

mattys91gt

Active Member
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#22
  • May 1, 2022
  • #22
7991LXnSHO said:
I do not have access to a Quarterhorse, but I like the idle lope.
I have not had problems with this air pump. But my 79 flung the Air pump pulley across the parking lot and it rolled onto the fairway when it was parked. No unusual noise when I drove it there, but everything came off the shaft.
Click to expand...
I'm sorry what's a quarter horse it's my first mustang I had all sport compacts my whole life or Hondas for the family
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
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Kearney, NE
May 1, 2022
#23
  • May 1, 2022
  • #23
Moates Quarterhorse

'QuarterHorse' for Fords [QH1] - $249.00 : Moates.Net

For a price of $249, the QuarterHorse delivers in unparalleled fashion. The QH plugs into the J3 port like a ordinary chip, but it allows bumpless, 100% realtime tuning AND datalogging while the engine is operating for all supported EEC-IV and EEC-V applications. You can log ANY parameter in...
www.moates.net

PMS is also good in this context.

PMS Tuning Tips

www.andersonfordmotorsport.com
 
Last edited: May 2, 2022

manicmechanic007

5 Year Member
Sep 26, 2017
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May 2, 2022
#24
  • May 2, 2022
  • #24
If you have a Ford processor and it does not see the EVP sensor move it assumes you've got a broken vacuum line or a broken EGR valve.
That makes the car run poor. Therrmactor has no effect on performance except backfire if air is going the wrong place at the wrong time.
Try making the EGR work and it needs a EVR too (the electric vent solenoid) that some of the older ones had
Then you can play with the washer size in the valve so you do no loose a ton of perf when running some EGR flow
The new Ford EGR valves came with a selection of washers. You had to pick one and stake it in place in a groove in the new valve
 

mattys91gt

Active Member
Feb 3, 2022
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May 2, 2022
#25
  • May 2, 2022
  • #25
manicmechanic007 said:
If you have a Ford processor and it does not see the EVP sensor move it assumes you've got a broken vacuum line or a broken EGR valve.
That makes the car run poor. Therrmactor has no effect on performance except backfire if air is going the wrong place at the wrong time.
Try making the EGR work and it needs a EVR too (the electric vent solenoid) that some of the older ones had
Then you can play with the washer size in the valve so you do no loose a ton of perf when running some EGR flow
The new Ford EGR valves came with a selection of washers. You had to pick one and stake it in place in a groove in the new valve
Click to expand...
so u stake a washer over the EGR ? vavle and I have the evr still hooked up but my friend butchered my vacuum lines again
 

manicmechanic007

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#26
  • May 2, 2022
  • #26
No
I am saying that a new ford valve comes with a big hole and you need to select a washer to go in the big hole
They are like one size fits all and the washer size is the difference
So if you want more performance you could select a washer with a smaller hole
The washer would just fall out of the groove in the new valve is why we had to stake them in (they designed them that way)
 

mattys91gt

Active Member
Feb 3, 2022
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Plymouth Massachusetts
May 2, 2022
#27
  • May 2, 2022
  • #27
manicmechanic007 said:
No
I am saying that a new ford valve comes with a big hole and you need to select a washer to go in the big hole
They are like one size fits all and the washer size is the difference
So if you want more performance you could select a washer with a smaller hole
The washer would just fall out of the groove in the new valve is why we had to stake them in (they designed them that way)
Click to expand...
man I wish one of you guys lived close to me u guys know so much it makes my head spin lol
 

manicmechanic007

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May 2, 2022
#28
  • May 2, 2022
  • #28
Man I wish I lived back east myself
Have an old friend in Boston
Try to keep your car stock and replace the air pump too if you can find one
They are less than a half a horse to run
PM me if you need
 

mattys91gt

Active Member
Feb 3, 2022
391
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Plymouth Massachusetts
May 2, 2022
#29
  • May 2, 2022
  • #29
manicmechanic007 said:
Man I wish I lived back east myself
Have an old friend in Boston
Try to keep your car stock and replace the air pump too if you can find one
They are less than a half a horse to run
PM me if you need
Click to expand...
I might try to put it back in I have the delete pulley in its place is it better to run the pulley or a short belt
 

mattys91gt

Active Member
Feb 3, 2022
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May 2, 2022
#30
  • May 2, 2022
  • #30
manicmechanic007 said:
Man I wish I lived back east myself
Have an old friend in Boston
Try to keep your car stock and replace the air pump too if you can find one
They are less than a half a horse to run
PM me if you need
Click to expand...
I have a question my engine bay is so hot but the gauge it's even half way I think I got sold a 160 thermostat is that the issue I'm heading home now to change the radiator fluid and see if that helps
 

manicmechanic007

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#31
  • May 2, 2022
  • #31
Sometimes if there is air on the temp sender instead of coolant they will read cold when they are hot
The underhood temp should be real hot and the thremostat if fuel injected should be 192 or 195
The underhood temp would be about the same with either stat
Think fan and shroud for any overheat (are they there and working)? Is the fan clutch any god etc.
 

mattys91gt

Active Member
Feb 3, 2022
391
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38
Plymouth Massachusetts
May 2, 2022
#32
  • May 2, 2022
  • #32
manicmechanic007 said:
Sometimes if there is air on the temp sender instead of coolant they will read cold when they are hot
The underhood temp should be real hot and the thremostat if fuel injected should be 192 or 195
The underhood temp would be about the same with either stat
Think fan and shroud for any overheat (are they there and working)? Is the fan clutch any god etc.
Click to expand...
that's all new but I think I have a 160 thermostat I'm going take it out and see, the fan shroud it's a little broken at the bottom and no plastic shroud under the car
 

manicmechanic007

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#33
  • May 2, 2022
  • #33
Also what you are thinking overheat may not be overheating at all?
The gauges are not real inaccurate but they are not all that accurate either
So, those older ones with electric fans just about do overheat before the processor commands cooling fan operation
Guys like me disregard the gauge and listen for the coolant to boil in the block
That sounds like holy crap loud Chonk, Chonk! Chonk!
That is overheat followed by blowing the radiator cap off
 

manicmechanic007

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Sep 26, 2017
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May 2, 2022
#34
  • May 2, 2022
  • #34
How many blades on the fan? Has a clutch or not? Close to the shroud?
All those matter some
 

mattys91gt

Active Member
Feb 3, 2022
391
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Plymouth Massachusetts
May 2, 2022
#35
  • May 2, 2022
  • #35
manicmechanic007 said:
Also what you are thinking overheat may not be overheating at all?
The gauges are not real inaccurate but they are not all that accurate either
So, those older ones with electric fans just about do overheat before the processor commands cooling fan operation
Guys like me disregard the gauge and listen for the coolant to boil in the block
That sounds like holy crap loud Chonk, Chonk! Chonk!
That is overheat followed by blowing the radiator cap off
Click to expand...
it's so hot under the hood but I wasn't sure if that's from the vacuum and EGR issue I have going on I open the hood and it's like I opened the oven
 

mattys91gt

Active Member
Feb 3, 2022
391
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38
Plymouth Massachusetts
May 2, 2022
#36
  • May 2, 2022
  • #36
manicmechanic007 said:
How many blades on the fan? Has a clutch or not? Close to the shroud?
All those matter some
Click to expand...
here's a picture I'm outside with the car
 

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manicmechanic007

5 Year Member
Sep 26, 2017
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Roy, Utah
May 2, 2022
#37
  • May 2, 2022
  • #37
That is the good fan setup IMHO
So if that fan clutch still has some resistance and has not lost any of its oil you should be good
The shroud should surround it
Someone may have cut yours to aid in removal
You could rivet or bolt in a piece of thin plastic to replace what is missing
 

mattys91gt

Active Member
Feb 3, 2022
391
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38
Plymouth Massachusetts
May 2, 2022
#38
  • May 2, 2022
  • #38
manicmechanic007 said:
That is the good fan setup IMHO
So if that bclutch still has some resistance and has not lost any of its oil you should be good
The shroud should surround it
Someone may have cut yours to aid in removal
You could rivet or bolt in a piece to replace what is missi
Click to expand...

manicmechanic007 said:
That is the good fan setup IMHO
So if that fan clutch still has some resistance and has not lost any of its oil you should be good
The shroud should surround it
Someone may have cut yours to aid in removal
You could rivet or bolt in a piece of thin plastic to replace what is missing
Click to expand...
o ya the heater core is bypassed
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,531
713
143
Roy, Utah
May 2, 2022
#39
  • May 2, 2022
  • #39
Plan on replacing that leaking heater core
It needs that heater core as an auxiliary heat exchanger
You can cheat if I remember right and pull the dash pad and the glovebox
Then pull the rh side of the dash back some and go in from the top
 

mattys91gt

Active Member
Feb 3, 2022
391
26
38
Plymouth Massachusetts
May 2, 2022
#40
  • May 2, 2022
  • #40
manicmechanic007 said:
Plan on replacing that leaking heater core
It needs that heater core as an auxiliary heat exchanger
You can cheat if I remember right and pull the dash pad and the glovebox
Then pull the rh side of the dash back some and go in from the top
Click to expand...
I watched that video I was like nope I'm not sure if it's bad over the summer I was baking in the car and it didn't have heat the car sat for a while before I got it that's why it has so many issues
 
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