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New car. Different issues.

  • Thread starter Thread starter a1machinista1
  • Start date Start date Nov 8, 2023
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A

a1machinista1

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Nov 8, 2023
#1
  • Nov 8, 2023
  • #1
So after my last Fox was hit. I just bought a new one and had it shipped home. No surprises but I was prepared for a few kinks to sort out. So how about some opinions? I'm certain you all will have a few. 89 GT GT40 HEADS E303 BBK Shortys, BBK X-PIPE with cats. Borla exhaust, 4.10s, EGR delete, smog pump delete, it runs well but a few issues, 1st runs rich when cold not as bad when warm, surges (jumps lightly)while cruising in 2nd or 3rd maybe 2k rpm.
Thoughts?
I don't plan on trying to emission test it. Looking to getting fuel under control and low rpm cruising a little better.. thanks guys and gals.
Besides these two things
 
A

a1machinista1

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#2
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I'm going to go out on a limb and guess that the general consensus is to put the emissions stuff back? I still have access to my one that was wrecked so parts are available to me. I'm hesitant to do that because in my head I'm doubtful that these cars are ever truly fully "fixed" ? Is it possible to get these running permanently with no CELs and no issues?
do I carb it? Pro flo 4?
Can the ecu be altered to work with what I have?
 

General karthief

wonder how much it would cost to ship you a pair
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#3
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I don't care for 4.10 gears so I'll leave that alone, I do think the E cam has to go, a more modern cam would make low rpm shelp'n around smoother.
You asked for opinions.
 

General karthief

wonder how much it would cost to ship you a pair
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#4
  • Nov 8, 2023
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a1machinista1 said:
Is it possible to get these running permanently with no CELs and no issues
Click to expand...
No CELs? yes, issues? No, it's an old car.
OH, NO carbs.
jmo
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#5
  • Nov 8, 2023
  • #5
I had an e303 cam and loved it in my 89 gt with similar mods as yours. Its old technology but works decent and sounds good. I ran one with cobra intake, gt40 heads, and a hit of nitrous. Made that ole 302 skidatle.

If it runs rich when cold check the iac sensor in the coolant bypass pipe. Would be better to pull codes though.

The emissions stuff doesn't need to go back on but you should get a tune. The mspnp2 is good ( I have one in my car ). It plugs right in and gives full control. Diyautotune is the place to go for that. Way more flexible than the factory computers. MS3 is even better but more for heavier modifications.

https://www.diyautotune.com/
 
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a1machinista1

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Ok, I bought a code reader for the last car so I'll that tomorrow after work. Is the mpnp2 the same as Microsquirt? I'll look at that now. I do have access to a tuner with a dyno. He offered to help me out before I bought this car.
Thank you
 
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a1machinista1

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#7
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Someone on corral was talking about this in an old post. Is this what you are talking about or equivalent?
 
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a1machinista1

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General karthief said:
I don't care for 4.10 gears so I'll leave that alone, I do think the E cam has to go, a more modern cam would make low rpm shelp'n around smoother.
You asked for opinions.
Click to expand...
I have been going with the attitude that the 4.10s won't be around long. A cam could be doable soon. I just got it a couple hours ago so I'll drive it around fir a week and see how it goes...
 

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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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#9
  • Nov 9, 2023
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Check codes, as stated above and look for vacuum leaks.
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#10
  • Nov 9, 2023
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All of the above and check the following:
What is the fuel pressure?
Is the MAF element clean?
What the condition of the air filter?
Are the valves adjusted correctly?
Injectors could be dirty and need cleaning - Pull the ones from the other car?
Tune up - fuel filter, cap, rotor, plug wires, and plugs - Pull the ones from the other car (obviously not the fuel filter)?
Check TPS and make sure it is functioning as intended.
Base idle reset?

Just things of the top of my head that I would do if did not know the car.
 
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a1machinista1

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#11
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I'm just thinking out loud until I get home tonight.
 

Mustang5L5

That is…until I whipped out my Bissell
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#12
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  • #12
My first thought is vacuum leak. I would smoke test and look for leaks and perform other diagnostic tsts before firing the parts cannon at it
 
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a1machinista1

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#13
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Mustang5L5 said:
My first thought is vacuum leak. I would smoke test and look for leaks and perform other diagnostic tsts before firing the parts cannon at it
Click to expand...
After work I will pull the codes and see what is there. Luckily I just bought a smoker for the last car so I'll do that as soon as I can. Doing home repairs and looking for a new house. So time is valuable. Thanks for the push
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#14
  • Nov 9, 2023
  • #14
I feel you on the house stuff. We close on the new one in a couple weeks and sell ours at the end of the month. Move all our crap in between and then settle in for the rest of the holidays and it’s Chili Bowl, a quick vacation, and then start building my long awaited shop.

Mike’s smoke test idea should definitely be at the top of my list every time but I just cannot seem to remember to suggest that.
 

2000xp8

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#15
  • Nov 11, 2023
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That is a very basic combo, been done a million times, doesn't need an aftermarket computer.
Carb? Hell no.
The E cam is fine, it's not a max power combination. Personally when i had one i kinda liked it, but the internet tends to not agree with that.
Regardless you will be wasting your time and money pulling and changing it.

How exactly do you know it's rich? Smell?
Pushrod engines with no emission equipment pretty much always smell like gas at start up.
It's probably the reason it has 4 cats, two pre-cats (which i believe are to work when the engine is not up to temp yet) and 2 cats.
 
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a1machinista1

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Nov 12, 2023
#16
  • Nov 12, 2023
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So my Sunday plans just got screwed up. No tile work or looking at houses today. Last night before bed I pulled codes.
35
67
10
34
41
91......
Ill pull out the smoker today.


It's rich when cold. I know because my wife told me, two or three times. It hasn't been started in a couple days. I'm thinking at some point today I'll clear the codes and take it for a drive.
As soon as I get some coffee in me I will go pull out the smoker.
 
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a1machinista1

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#17
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I need to see if I can track down the guy that built this car. Atleast I can get an idea of where he left off. The guy I bought it from didn't seem to know much. Or he did and he wasn't saying?
 
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a1machinista1

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#18
  • Nov 12, 2023
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Ok, I'm going to slow down and back up a bit. I need to evaluate what my starting point is. I need to figure out some history of what has been done..I'm going to pull out the smoker and then take a look around.
 

2000xp8

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#19
  • Nov 12, 2023
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I doubt the previous owners would be any help, if they knew what they were doing, they probably would have fixed it themselves.
You are probably the first guy to ever run codes on it.

Cross reference your code list and check to see if all the parts in those codes are in fact installed and the wiring is intact.

I'd put the EGR back on.

Just chip away at the list.
 
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a1machinista1

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#20
  • Nov 12, 2023
  • #20
Ok, I think we have a winner on the vacuum leak. There are two vacuum ports on the underside of the plenum. A large one above the driver's valve cover and on the bottom of the plenum.
 
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