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help, i think i have a major problem!!

  • Thread starter Thread starter tomst9
  • Start date Start date Aug 19, 2004

tomst9

Founding Member
Jun 17, 2002
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Bethlehem Pa
Aug 19, 2004
#1
  • Aug 19, 2004
  • #1
My car isn't making the power it should, so i hooked up the code scanner up to it to see if i had any codes. I did a koeo test and i cam up with code 22 and code 34. I then tried to start it and it wouldn't start. I was getting spark and fuel. So i disconnected the battery cables and let it sit over night. The next morning i hooked it back up and it started, but it ran like absolute crap and the check engine light was on, which it wasn't before. So i turned it off and tried to run a koer test and when i started it the code scanner said it wasn't making a connection. So i disconnected it and tried to start it and it wouldn't start again. So i disconnected the cables again and let i sit for about four hours. I tried to start it again, and i still couldn't get it to fire. I i let it sit overnight with the cables off and in the morning i hooked them back up and it started and ran again, but real bad. I turned it off and tried to run another koeo test and it said the it couldn't make a connection. and once again after disconnecting the tool, it won't start. What the hell happened. It is getting fuel and spark. I pulled the plugs to see if it was getting floooded and the weren't wet, but i smell the fuel coming out of the exhaust. \
Any ideas?
thanks
tom
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Aug 19, 2004
#2
  • Aug 19, 2004
  • #2
o2's might have locked up.................. when they go it will in some cases run pig rich..................dump to much fuel run like ass and destroy the cats...........
 

tomst9

Founding Member
Jun 17, 2002
851
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Bethlehem Pa
Aug 19, 2004
#3
  • Aug 19, 2004
  • #3
but, if i remeber correctly, doesn't the computer run on a closed loop until it gets warmed up and then it will begin to read from the sensors?
 

tomst9

Founding Member
Jun 17, 2002
851
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Bethlehem Pa
Aug 19, 2004
#4
  • Aug 19, 2004
  • #4
ttt
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Aug 20, 2004
#5
  • Aug 20, 2004
  • #5
Tom, you are on the right track. the puter runs in OPEN loop till it warms up. O2's are not utilized during open loop or at WOT (ever).

is the pump priming? im not a MAF guy, but ive read of MAF's goin bad and not allowing one to start the car.

the lack of scanning ability is weird. can you confirm that the EEC relay and FP relay is/are working at all times?

im sorry if im asking things you addressed already, but sometimes confirmation or hitting it from a different angle can make a lightbulb illuminate (not mine, but others'. LOL).

good luck, Tom.
 

tomst9

Founding Member
Jun 17, 2002
851
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Bethlehem Pa
Aug 20, 2004
#6
  • Aug 20, 2004
  • #6
thanks for the replies,
The pump is definetly priming. Where is the eec relay? Is there an easy way to pull the computer, i was looking at it and it looks like i will have to pull the whole dash like if i were to be doing a heater core?
thank
tom
 
S

Shauns GT

Member
Feb 6, 2003
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Brandon, Manitoba, Canada
Aug 20, 2004
#7
  • Aug 20, 2004
  • #7
The EEC relay is located right above the computer in behind the kickpanel on the right hand side of the dash. You probably have to pull the compter down to get to it. Ive had to replace mine twice now. Its real easy to spot when the computer is out its the only relay there.
 
S

Shauns GT

Member
Feb 6, 2003
101
0
16
Brandon, Manitoba, Canada
Aug 20, 2004
#8
  • Aug 20, 2004
  • #8
oh yeah to pull the computer you gotta loosen out the nut on the bottom that holds the big wiring harness connector in then remove the bolt that is attached to thebottom of the plastic bracket and carefully pull the plastic bracket away and the computer should basically fall out. ITs recomended that you ground yourself so that you dont static spark the computer.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Aug 21, 2004
#9
  • Aug 21, 2004
  • #9
if the pump is priming, the EEC relay is working, as far as i know. i only asked about the FP and EEC relays above, in case you had an intermittant problem with one of the relays. does not sound so.
 

jrichker

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Dublin GA
Aug 21, 2004
#10
  • Aug 21, 2004
  • #10
Code 22 MAP (vacuum) or BARO signal out of range. The MAP or BARO sensor is pretty much the same sensor for both Mass Air & Speed Density cars. The main difference is where it is connected. Mass Air cars vent it to the atmosphere, while Speed Density cars connect it to the intake manifold vacuum. Its purpose is to help set a baseline for the air/fuel mixture and changes in barometric pressure. The MAP or BAP sensor puts out a 5 volt square wave that changes frequency with variations in atmospheric pressure. The base is 154 HZ at 29.92" of mercury - dry sunny day at sea level, about 68-72 degrees. You need an oscilloscope or frequency meter to measure it.

Baro or MAP test using frequency meter - run the test key on engine off. The noise from the ignition system will likely upset the frequency meter. I used a 10 x oscilloscope probe connected from the frequency meter to the MAP/BAP to reduce the jitter in the meter's readout.

If it is defective, your air/fuel ratio will be off and the car’s performance & emissions will suffer

Code 34 EGR voltage above closed limit - Failed sensor, bad or missing signal ground, carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the EGR valve by mouth. If you can, replace the EGR valve ($85-$95).

The combination of symptoms point to a possible bad signal ground. Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohm. Next check the resistance between the black/white wire on the MAP/BAP sensor and the negative battery post. It should be less than 1 ohm. Repeat the process for the black/white wire on the EGR sensor and the negative battery post. It also should be less than 1 ohm as well.
 
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