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cant keep the car running!!!

  • Thread starter Thread starter NO BRAKES
  • Start date Start date Feb 9, 2006

NO BRAKES

New Member
Feb 8, 2006
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Avon Lake, Ohio
Feb 9, 2006
#1
  • Feb 9, 2006
  • #1
ok... I am more or less a carburater guy. I am trying to get this fuel injected car to run right. I have a basically stock bottom end. I have been told i made a mistake with the e303 cam. GT40 intake and heads. I have a new tps. A new IAC valve. Two new o2 sensors. I have the tps adjusted properly. With the IAC valve unpluged the car wont start, so i guess the iac valve works. The car when cold will idle at 800 with very little problem. Once the car gets warm at an idle the car seems to start to lope. the idle goes from 700 to 1000rpm's. Then it goes down and eventually stalls. What can i do to keepit running? Right now i have it adjusted to idle at 1000 just to keep it running. Do i maybe have a bad mass air meter? I believe it is a 70mm. the mass air is clean if that matters.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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129
Feb 9, 2006
#2
  • Feb 9, 2006
  • #2
I would yank codes first, but it seems to me your idle is set too low. The computer cant take away air (not really an issue for you) but it can add air. So the surging could be from the IAC trying to get the idle somewhere decent.

On a MAF car, a lot of folks (esp with a cam like that) set the warm idle with the IAC disconnected (so it isnt needed for a hot idle with no load). Then you know when the IAC is connected, it will have enough air (ergo idle without stalling).

I have been playing this game on my 94. I now have a side effect of a cold idle of 1500 RPM for 5 seconds, before it settles down to 1000 and then 800 RPM (all within 30 seconds).

My two cents. Good luck.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Feb 9, 2006
#3
  • Feb 9, 2006
  • #3
Here is some ancillary info that might be useful.

Good luck.
 

NO BRAKES

New Member
Feb 8, 2006
129
0
0
Avon Lake, Ohio
Feb 10, 2006
#4
  • Feb 10, 2006
  • #4
that sounds like a good idea. I never thought of unplugging the IAC when the car was hot. i will give that a try. Thanks for the input!!
 

hotrodredneck

New Member
Jul 28, 2004
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0
Newport News Va
Feb 10, 2006
#5
  • Feb 10, 2006
  • #5
the cam might be confusing the comp man
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Feb 10, 2006
#6
  • Feb 10, 2006
  • #6
somethings not right. its not the cams fault.
 

NO BRAKES

New Member
Feb 8, 2006
129
0
0
Avon Lake, Ohio
Feb 10, 2006
#7
  • Feb 10, 2006
  • #7
i really dont know what to do about this. I just took the car for a spin and it stalled when i went to stop!! I dont get it!!!!
 

legalize420

Active Member
May 21, 2005
1,541
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37
South Florida
Feb 10, 2006
#8
  • Feb 10, 2006
  • #8
my car never really just died like that, and if you have a fox your computer gets along with the cam better then mine. i do get the cold start surge in the morning but it goes away. it used to do it on hot starts but i recently changed the ect and it got better. only happened once or twice since changing it but thats better then everytime. as hissin said, its a good idea to see if any codes come up. what maf and injectors do you have?
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
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37
Jersey Shore
Feb 10, 2006
#9
  • Feb 10, 2006
  • #9
I have the same cam but Windsor Jr heads still cast iron. I used to have the same problem for a few months but after some little work now she runs stable real nice hot or cold. At one time it would surge cold then run good hot and another time it would run good cool then suck when getting hot...Start from scratch, go down the whole reset base idle list and dont forget reset the tps when ur done and disconnect the battery to reset the computer, also try cleaning the mass air sensor...I disconnected the battery on mine the other day and WOW it feels like a new car and ran MINT,had tons of more power, ran soooo smooth etc. but its starting to go back to its oldself so I got to pull the codes and see why its doing that.
 

jrichker

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Dublin GA
Feb 10, 2006
#10
  • Feb 10, 2006
  • #10
See the sticky "Help me create the Surging Idle Checklist" at the top of the forum for help with your idle problems. The first post in the sticky has almost all the details you need.
 
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