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Car runs like chit all the sudden????

  • Thread starter Thread starter gcomfx.com
  • Start date Start date Nov 12, 2004
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gcomfx.com

Founding Member
Oct 22, 2002
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Republic, MO
Nov 12, 2004
#1
  • Nov 12, 2004
  • #1
Car runs like chit all the sudden???? EGR problems...

Car ran fine when I went to lunch yesterday. I started it up to go home and it runs like an old beat up truck. Idles like it has a monster cam, but sounds like crap. Hesitates, and doesn't show power until 4,000+ and then it just doesn't feel like it's all there.

I backed it out of the garage this morning for work and it was still doing it. Didn't have much time, but I did pop the hood and heard my EGR tube leaking. It has the heat boot on it and I could move or squeeze it and the sound would change.

Could that be the only problem? Going to try to run the codes this w/e.
 

OrangeMustangGt

Founding Member
Mar 7, 2002
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Cape Cod, MA
Nov 12, 2004
#2
  • Nov 12, 2004
  • #2
hmm i wouldent think an egr would casue so much problems,
 

SN95StangMan

New Member
Jul 5, 2003
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Lynwood, CA
Nov 12, 2004
#3
  • Nov 12, 2004
  • #3
It did for me when I installed the intake. Had a horrible leak and ran like shyte. Acted pretty much the way he described. Hopefully that's the only problem.
 

gcomfx.com

Founding Member
Oct 22, 2002
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56
Republic, MO
Nov 12, 2004
#4
  • Nov 12, 2004
  • #4
I hope that's all it is. Thanks for the feedback. It was raining yesterday, which is the only thing out of the ordinary, that and it got really cold. Guess the water and temp change cracked it.

Time to delete the EGR and get more room under the hood.
 

gcomfx.com

Founding Member
Oct 22, 2002
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Republic, MO
Nov 12, 2004
#5
  • Nov 12, 2004
  • #5
Any other suggestions??? Just curious incase it's not the EGR tube.
 

urban96

bubb rubb says:"woo woooooo"
Founding Member
Sep 24, 2002
3,464
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Syracuse, NY
Nov 12, 2004
#6
  • Nov 12, 2004
  • #6
maybe a vaccume line?
 

greenlantern

Member
Jul 11, 2004
265
1
17
St Louis Mo
Nov 12, 2004
#7
  • Nov 12, 2004
  • #7
Sounds like oxygen sensor to me.
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Nov 12, 2004
#8
  • Nov 12, 2004
  • #8
Did it run OK cold and then get bad after warming up? Mine is doing that now ...

Any pinging?

When I had a vacuum leak it ran better at low rpms and ping like crazy at high rpms ...

If it's O2s, then it would run OK at WOT.
 

Car Nut

Founding Member
Jul 6, 2000
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Snellville, Georgia (Atlanta area)
Nov 12, 2004
#9
  • Nov 12, 2004
  • #9
My car sounded like the way your described a couple times. Happened once and then not again for a couple weeks, then it was real bad. Turned out to be my catalytic converters had broken apart (all four of them, in fact). Not sure if you have cats or not, but if so, check them out. My idle and everything was messed up and the exhaust didn't sound right either.

Ford ran a diagnostic test and found the cats were bad. They offered to replace my mid-pipe with a stock one for over $2,000.00. I laughed and said I'd just grab an X pipe for $500 from a local shop and improve the sound and performance. And that's what I did.
 

gcomfx.com

Founding Member
Oct 22, 2002
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56
Republic, MO
Nov 17, 2004
#10
  • Nov 17, 2004
  • #10
I decided to test my the EGR tube to see if I was chasing the right culprit. I filled the TWO cracks in the rippled part of the tube with Muffler Bondo stuff.

Let it set overnight... then this morning fired it up. Didn't help at all. Immediate the idle was surging and running like chit again.

My cats are aftermarket and don't have but 30,000 or so miles on them and they are high-flow, so they don't have a whole lot of stuff in them.

Going to try to pull the codes tonight or tomorrow night. (I would like to hit the track Sunday, but it's not looking good.)
 

gcomfx.com

Founding Member
Oct 22, 2002
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Republic, MO
Nov 17, 2004
#11
  • Nov 17, 2004
  • #11
Guess I spoke to soon? I checked everything I could think of tonight.... nothing. I fired it up, and it ran like chit... I kept trying to listen for ANYTHING that might point me in the direction of a problem. Nothing....

Throttling the car up and letting off, would almost kill the car. The muffler putty stuff smoked a bit.. but nothing major.

Then at the edge of my vision I seen movement in the EGR. I reved it a couple times and it moved some more then stayed where it was at. All the sudden the rough idle and stuttering went away.

I took it out for a test drive and the old car was back to normal. Still surges as you coast down a hill.... but it now runs fine.

Guess my question is...

did the computer have to learn the EGR tube was now fixed?

Or was the EGR plunger stuck and finally worked it's way free?

Or is my car just female and this week was her time of the month?

I may be headed to the track Sunday! Time to go check the weather.
 
B

Black70Fastback

New Member
Dec 14, 2003
319
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0
Dyer, IN
Nov 17, 2004
#12
  • Nov 17, 2004
  • #12
dont you guys name your cars? and of course they are all female names
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
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56
Republic, MO
Nov 17, 2004
#13
  • Nov 17, 2004
  • #13
Mine has many names at times... when I'm losing at the track, it's "come on ****** you know you can beat that car!"
 
S

Silver85TC

New Member
May 28, 2003
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Nov 17, 2004
#14
  • Nov 17, 2004
  • #14
1st thing to do in your situation is check for any computer error codes. Something changed suddenly which could throw a code.
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
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56
Republic, MO
Nov 18, 2004
#15
  • Nov 18, 2004
  • #15
My fuel pressure is at 38 psi with vacuum UN hooked.

When I run too much fuel, the CEL light will come on randomly while driving.

Right now it comes on when I'm in O/D and pulling up a hill... when I top the hill, the car is kinda loading up and the CEL will come on for 5 seconds. It won't come back on til another hill.

I may lower it some more....

My friends think my EGR is fubared and screwing with things. Guess I'm going to try to delete it soon.
 

mystang94gt

New Member
Jun 14, 2004
951
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Bay Area, CA
Nov 18, 2004
#16
  • Nov 18, 2004
  • #16
I had problems with my EGR before and it made the car surge a lot. If you have a code scanner use it. I ran mine and it popped up with the EGR code. Swapped it out (damn CA smog laws) and the car ran fine. If its sticking it will work sometimes and then get stuck and run like ****. One thing to consider is that the EGR does NOTHING at WOT. So if you floor it and it runs ok then EGR may be your problem. Because EGR valve only works at part throttle. Good luck bro!
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
0
56
Republic, MO
Nov 19, 2004
#17
  • Nov 19, 2004
  • #17
EGR stuck again.... It's finding it's way to the dumpster tonight.
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
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56
Republic, MO
Nov 19, 2004
#18
  • Nov 19, 2004
  • #18
Here's some EGR information a buddy sent me. He works at Ford in Dearborn.

1995 PCED OBD I A SECTION 10A: Exhaust Gas Recirculation (EGR) Systems

--------------------------------------------------------------------------------

EGR System Descriptions


Vacuum Operated EGR Systems
The Exhaust Gas Recirculation (EGR) System is designed to reintroduce exhaust gas into the combustion cycle lowering combustion temperatures and reducing the formation of Oxides of Nitrogen (NOx).

There are two basic types of EGR systems:

The Pressure Feedback Electronic (PFE)/Differential Pressure Feedback Electronic (DPFE) System (9J460 + 9D475)
The EGR Valve Position (EVP) System 9F483 (9H473 + 9G428)
The amount of exhaust gas reintroduced and the timing of the cycle varies by calibration and is controlled by factors such as engine speed, engine vacuum, exhaust system back pressure, coolant temperature and throttle angle. All EGR valves are vacuum actuated. The vacuum diagram is shown on the emission decal for each calibration.


Pressure Feedback Electronic EGR (PFE/DPFE) Systems
PFE is a subsonic closed loop EGR system that controls EGR flow rate by monitoring the pressure drop across a remotely located sharp-edged orifice. The system uses a pressure transducer as the feedback device and controlled pressure is varied by valve modulation using vacuum output of the EGR Electronic Vacuum Regulator (EVR) solenoid (9J459). With a PFE system (Figure 1) , the EGR valve serves only as a pressure regulator rather than a flow metering device. The Differential Pressure Feedback Electronic EGR (DPFE) system (Figure 2) operates in the same manner except it directly monitors the pressure drop across the metering orifice. This allows for a more accurate assessment of EGR flow requirements.





Figure 1: Typical Pressure Feedback Electronic EGR (PFE) System




Figure 2: Differential Pressure Feedback Electronic EGR (DPFE) System
System Components
PFE EGR Valve
The PFE EGR valve (9D460) (Figure 3) is a conventional ported EGR valve. The service replacement for this valve is 9D475 which does not include the pickup tube/plug. The original pickup tube/plug should be used with the new service valve (9D475).





Figure 3: Typical PFE EGR Valve
PFE and DPFE Sensors
The Pressure Feedback Electronic EGR (PFE) and Differential Pressure Feedback Electronic EGR (DPFE) sensors (9J460) (Figures 4 and 5) convert a varying exhaust pressure signal into a proportional analog voltage which is digitized by the Powertrain Control Module (PCM). The PCM uses the signal received from the PFE or DPFE sensor to compute the optimum EGR flow.





Figure 4: Pressure Feedback Electronic EGR (PFE) Sensor




Figure 5: Differential Pressure Feedback Electronic EGR (DPFE) Sensor

EGR Valve Position (EVP) System
The EVP EGR Valve (Figure 6) is required in EEC systems where EGR flow is controlled by the Powertrain Control Module (PCM) through an EGR Valve Position (EVP) sensor attached to the valve.

The valve is operated by a vacuum signal from the EGR Electronic Vacuum Regulator (EVR) Solenoid (9J459) which actuates the valve diaphragm.

As supply vacuum overcomes the spring load, the diaphragm is actuated. This lifts the pintle off its seat allowing exhaust gas to recirculate (flow). The amount of flow is proportional to the pintle position. The EVP sensor mounted on the valve sends an electrical signal of its position to the PCM.





Figure 6: Typical EGR Valve Position (EVP) System
System Components
EVP EGR Valve
The EGR valve (Figures 7 and for this system is a vacuum operated EGR valve which maintains a sonic flow in the valve seat/pintle area.

The EVP EGR valve assembly (9F483) is not serviceable. The EVP sensor (9G428) and EGR valve (9H473) must be serviced separately.





Figure 7: EVP EGR Valve—5.0L Mustang and 5.8L Truck (Lightning)




Figure 8: EVP EGR Valve—All Other Applications
EGR Valve Position (EVP) Sensor
The EVP sensor (9G428) (Figure 9) provides the EEC system with a signal indicating position of the EGR valve.





Figure 9: EGR Valve Position (EVP) Sensor

EGR Electronic Vacuum Regulator (EVR) Solenoid
The EGR Electronic Vacuum Regulator (EVR) solenoid (9J459) (Figure 10) is an electromagnetic device which controls vacuum output to the EGR valve. An electric current in the coil induces a magnetic field in the armature which pulls on a disk closing the vent to atmosphere. The Powertrain Control Module (PCM) outputs a duty cycle to the EVR which regulates the vacuum level to the EGR valve. As the duty cycle is increased, so is the vacuum signal to the EGR valve. The vacuum source is manifold vacuum.





Figure 10: EGR Electronic Vacuum Regulator (EVR) Solenoid

Vacuum Reservoir
The Vacuum Reservoir (9E453) (Figure 11) stores vacuum and provides "muscle" vacuum. It prevents rapid fluctuations or sudden drops in a vacuum signal such as those seen during an acceleration period.





Figure 11: Vacuum Reservoirs
Diagnosis
When charged initially with 51-67 kPa (15-20 in-Hg) vacuum, vacuum loss shall not exceed 2 kPa (.5 in-Hg) in 60 seconds. If it does, replace the reservoir.


Vacuum Check Valve
A vacuum check valve (12A197) (Figure 12) blocks airflow in one direction and frees airflow in the other direction. The check side of this valve will hold the highest vacuum seen on the vacuum side. If not, replace it.





Figure 12: Vacuum Check Valve
Diagnosis
Apply 54 kPa (16 in-Hg) vacuum to "check" side of valve and trap. If vacuum remains above 50.6 kPa (15 in-Hg) for 10 seconds, the valve is acceptable.




--------------------------------------------------------------------------------

1995 PCED OBD I A SECTION 10A: Exhaust Gas Recirculation (EGR) Systems

--------------------------------------------------------------------------------

EGR System Diagnosis By Symptom
Condition Possible Source Action
Rough Idle Cold
EGR valve malfunction.
RUN Quick Test.

EGR flange gasket leaking.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specif ication.

Vacuum leak at EVP sensor.
REPLACE O-ring seal and TIGHTEN EVP sensor attaching nuts to specification.

EVR solenoid malfunction.
RUN Quick Test.

EGR valve contamination.
CLEAN EGR valve.

Rough Idle Hot
EGR valve malfunction.
RUN Quick Test.

EGR flange gasket leaking.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

Vacuum leak at EVP sensor.
REPLACE O-ring seal and TIGHTEN EVP sensor attaching nuts to specification.

EVR solenoid malfunction.
RUN Quick Test.

EGR valve contamination.
CLEAN EGR valve.

Rough Running, Surge, Hesitation, Poor Part Throttle Performance—Hot
EGR valve malfunction/erratic operation.
PERFORM EGR valve functional diagnosis.

EGR valve contamination.
CLEAN EGR valve and if necessary, replace EGR valve.

EVR solenoid malfunction.
RUN Quick Test.

Pressure/Vacuum signal hose(s) leak (PFE/DPFE).
REPLACE hose(s).

Engine Stalls On Deceleration—Hot
EGR valve malfunction.
PERFORM EGR valve functional diagnosis.

EVR solenoid malfunction.
RUN Quick Test.

EGR valve contamination.
CLEAN EGR valve and if necessary, replace EGR valve.

Engine Spark Knock or Ping
EGR valve malfunction.
PERFORM EGR valve functional diagnosis.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

Blocked or restricted passages in valve or spacer (EVP).
CLEAN passages in EGR spacer and EGR valve.

Engine Stalls At Idle—Cold
EGR valve malfunction.
PERFORM EGR valve functional diagnosis.

EGR flange gasket leaking.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EVR solenoid malfunction.
RUN Quick Test.

EGR valve contamination.
CLEAN EGR valve.

Engine Stalls At Idle—Hot
EGR valve malfunction.
PERFORM EGR valve functional diagnosis.

EGR flange gasket leaking.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve contamination.
CLEAN EGR valve and if necessary, replace EGR valve.

Vacuum leak at EVP sensor.
REPLACE O-ring seal and TIGHTEN EVP sensor attaching nuts to specification.

EVR solenoid malfunction.
RUN Quick Test.

Engine Starts But Will Not Run—Engine Hard To Start Or Will Not Start
EGR valve malfunction.
PERFORM EGR valve functional diagnosis.

EGR flange gasket leaking.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EGR valve attaching nuts or bolts loose or missing.
REPLACE flange gasket and TIGHTEN valve attaching nuts or bolts to specification.

EVR solenoid malfunction.
RUN Quick Test.

EGR valve contamination.
CLEAN EGR valve.


1995 PCED OBD I A SECTION 10A: Exhaust Gas Recirculation (EGR) Systems

--------------------------------------------------------------------------------

EGR: EGR System Functional Diagnosis

--------------------------------------------------------------------------------

EGR1 CHECK SYSTEM INTEGRITY
Check vacuum hoses and connections for looseness, pinching, leakage, splitting, blockage and proper routing.
Inspect EGR valve for loose attaching bolts or damaged flange gasket.
Does system appear to be in good condition and vacuum hoses properly routed?
Yes No
GO to EGR2 . SERVICE EGR system as required. RE-EVALUATE symptom.

EGR2 CHECK EGR VACUUM AT IDLE
Run engine until normal operating temperature is reached.
With engine running at idle, disconnect EGR vacuum supply at the EGR valve and check for a vacuum signal.
Note: The EVR solenoid has a constant internal leak. You may notice a small vacuum signal. This signal should be less than 3.4 kPa (1.0 in-Hg) at idle.

Is EGR vacuum signal less than 3.4 kPa (1.0 in-Hg) at idle?
Yes No
GO to EGR3 . RECONNECT EGR vacuum hose. INSPECT EVR solenoid for leakage. RUN Quick Test.

EGR3 CHECK EGR VALVE FUNCTION
Install a tachometer, Rotunda 059-00010 or equivalent.
Disconnect the Idle Air Control (IAC) solenoid (9F715) electrical connector.
Remove and plug the vacuum supply hose from the EGR valve nipple.
Start engine, idle with transmission in NEUTRAL, and observe idle speed. If necessary, adjust idle speed according to Section 12A.
Note: If the engine will not idle with IAC solenoid disconnected, provide an air bypass to the engine by slightly opening the throttle plate or by creating an intake vacuum leak. Do not exceed a typical idle rpm.

Slowly apply 5-10 inches of vacuum to the EGR valve nipple using a hand vacuum pump, Rotunda 021-00014 or equivalent.
Does idle speed drop more than 100 rpm with vacuum applied and return to normal (± 25 rpm) after the vacuum is removed?
Yes No
The EGR valve is OK. UNPLUG and RECONNECT the EGR valve vacuum supply hose. RECONNECT the IAC solenoid connector. REFER to Diagnostic Routines, Section 2A. INSPECT the EGR valve for blockage or contamination. CLEAN the valve using Rotunda 021-80056 EGR valve cleaner. INSPECT valve for vacuum leakage. REPLACE if necessary. If EGR valve is OK, inspect the EGR flow path in the intake manifold for blockage.




--------------------------------------------------------------------------------


Rotunda Equipment Model Description
021-00014 Vacuum Pump
021-80056 EGR Valve Cleaner
059-00010 Tachometer
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Nov 19, 2004
#19
  • Nov 19, 2004
  • #19
gcomfx.com said:
A buddy works at Ford in Dearborn.
Click to expand...
Holy crap! That's an awesome resource.

:OT: Maybe he can dig up a document that describes how the CBAZA strategy works. For those who are not familiar with what CBAZA is, it's the code for the algorithm that is implemented on EEC our cars use.
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
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56
Republic, MO
Nov 19, 2004
#20
  • Nov 19, 2004
  • #20
His username is 1988Bullitt on our club site. Feel free to ask him yourself.
 
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