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Wierdest Idle Issue Ever!!!!

  • Thread starter Thread starter Ford50HO
  • Start date Start date Aug 28, 2005
F

Ford50HO

New Member
Jan 27, 2004
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Sacramento, California
Aug 28, 2005
#1
  • Aug 28, 2005
  • #1
I've searched the threads but have had no luck. My car is all stock with an e cam. it idles just fine with my mass air meter unplugged and it even drives, its slow and runs lean and heats up quickly but is driveable. if the car is idling and i plug in the mass air it immediately putters and dies.

so far i have cleaned the throttle body and egr and valve and mass air meter to the point where you could eat off of them. i have checked the pcv valve and all my vaccum lines. i have a new idle air, tps and o2 sensors. basically an all new ignition system from plugs to coil. everyone i know is completely stumped. we have put on 4 different mass air meters including ones of of perfectly running cars. nothing seems to work.

engine computer maybe?

any help would be appreciated. its been sitting on my driveway since ive gotten it because i havent been able to fix the problem. ive been spending spare time doing body work and interior and stereo work. but its time for the car to drive. thanks guys
 

ram360

Founding Member
Oct 19, 2002
2,162
1
59
Pennsylvania
Aug 28, 2005
#2
  • Aug 28, 2005
  • #2
did you try pulling any codes? If you didn't I would say that would be a good start.
 
F

Ford50HO

New Member
Jan 27, 2004
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Sacramento, California
Aug 28, 2005
#3
  • Aug 28, 2005
  • #3
i want to do that but i dont have a code scanner. and its not driveable to take it to a shop really. im thinking of going and buying one from kragen for 70 bucks just cuz this is pissing me off so bad.
 
N

newbee90gt

New Member
Aug 24, 2003
32
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0
Oceanside,Ca
Aug 28, 2005
#4
  • Aug 28, 2005
  • #4
i did a Trickflow cam to my friends cobra and we had the same problem couldn't keep it running. come to find out the little wire in the mass air meter was broken. hard to notice for us but it was a simple fix
 

ram360

Founding Member
Oct 19, 2002
2,162
1
59
Pennsylvania
Aug 28, 2005
#5
  • Aug 28, 2005
  • #5
Ford50HO said:
i want to do that but i dont have a code scanner. and its not driveable to take it to a shop really. im thinking of going and buying one from kragen for 70 bucks just cuz this is pissing me off so bad.
Click to expand...

You don't need a scanner. Just use a test light and jumper wire.clicky
 

bubba-dough

Active Member
Dec 28, 2004
1,044
2
38
Indiana
Aug 28, 2005
#6
  • Aug 28, 2005
  • #6
By any chance where the fuel injectors changed by the previous owner (since you said that it has been like this since you bought it) and the mass air meter never changed? Just a thought.
 
F

Ford50HO

New Member
Jan 27, 2004
19
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0
Sacramento, California
Aug 28, 2005
#7
  • Aug 28, 2005
  • #7
i unplugged my battery all last night so that the computer would reset. i had to unplug the mass air so it would idle when i started it today so it could have codes pop up. the i did the koeoff and the koeon tests and i pulled two different egr valve codes and a tps voltage to low to read code and also the mass air meter unplugged code. i also got some valve body code. and the shift solenoid 1 malfunction code. i had to have the meter unplugged so it could idle.

it idles even with the tps and the valve codes with the meter unplugged. i am changing my egr to the one off my old car and resetting my tps tomorrow. anyone have any ideas? thanks guys.

anyone know where the shift solenoid is and how to replace that too?

i know i have alot of questions but i really need the help thanks guys.
 
F

Ford50HO

New Member
Jan 27, 2004
19
0
0
Sacramento, California
Aug 28, 2005
#8
  • Aug 28, 2005
  • #8
the car is an 89 but the motor is out of a 91 :damnit: but it does have the stock injectors. if the stuff i listed above doesnt fix it im gonna try and swap the injectors and harness and the engine computer. im so confused.
 
M

mcclean

New Member
Oct 24, 2004
14
0
1
Oct 16, 2005
#9
  • Oct 16, 2005
  • #9
you need a DVOM and some values for the mass air to figure this out. Start by using a good MAF. Even KOEO the maf should have some values. With KOEO the mass air should be at 0 gps 0v DC and 4-8 gps at idle (.6-.8v DC). Make sure these values are at thier respected pins on the ECM. Make sure there is continuity in all the wires from harness end to pin. Could be a short in the harness for the mass air causing bad values to get to the computer. With it unplugged its getting no values and stays in limp home mode. But if its plugged in and getting bad values it could stun the computer causing it to die.
 

jrichker

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Mar 10, 2000
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Dublin GA
Oct 17, 2005
#10
  • Oct 17, 2005
  • #10
Post the exact codes. Some of the EGR codes point to wiring faults that can major mess up the way the car runs. The TPS too low is also a pointer in that direction.

Once you have posted the codes, I can tell if it is a wiring problem and give you some ponters th help get it fixed.
 
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