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Discussion Starter · #1 ·
**SORRY YOUR SUGGESTIONS DIDNT WORK!! MORE PLEASE!**

1987 5.0 manual transmission speed density CA car, starts up fine, idles about 850 rpm no prob. The problem is intermittent surgeing-bucking-roughness esp in 2nd gear at part throttle following shift. I have replaced the fuel pump with new unit, fuel filter, plugs, cap and rotor and wire... but thats it... Please any suggestions?

=============AFTER trying suggestions===========

NOPE! I cleaned and opened up the 20 pins that connect the engine wiring to the computer wiring, Checked the TPS all along its range... no dead spots at all, CANT figure out what’s up!!! What would a faulty EGR valve be like? I have checked again and again for vacuum leaks, pretty sure I've got them all, but SITLL ITS like only 5% of the time, but it feels like the engine just cuts out when I am accelerating, 95% its just into 2nd gear, a little after I have started slowly giving gas... but I can feel a “unrhythm” sometimes at random conditions, but like I said, only like 1 day out of the week; the car is my daily driver

!!.H.E.L.P.!!

<font size=-1>[ This Message was edited by: 67fastback on 5/9/06 1:34pm ]</font>
 

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Discussion Starter · #2 ·
Did it today too... its only after it warms up................. ........................ .................... ...............
 

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Discussion Starter · #4 ·
That article focuses on "idle surge" however, my car idles smoothly at around 850 rpm... it is only under load at part throttle that I get a choppy stumble


but thank you I will try cleaning, and opening the contacts of the ecc connectors
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<font size=-1>[ This Message was edited by: 67fastback on 4/13/06 11:38am ]</font>
 

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throttle position has a dead spot?
 

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On 2006-04-16 16:47, wildosvt01 wrote:
throttle position has a dead spot?
That would be my speculation as well. Sometimes the T.P. sensor can get a spot that is phyically worn, had that happen on my 87.


cheers
Ed N.
 

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Discussion Starter · #8 ·
Thanks for the good idea! .. I am wondering though: could this dead spot be so intermittent? I mean; days will pass with no problem and then maybe the prob happens a few times in 1 day... Its my daily driver................ .......................

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<font size=-1>[ This Message was edited by: 67fastback on 4/17/06 11:43am ]</font>
 

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Discussion Starter · #9 ·
NOPE! I cleaned and opened up the 20 pins that connect the engine wiring to the computer wiring, Checked the TPS all along its range... no dead spots at all, CANT figure out what’s up!!! What would a faulty EGR valve be like? I have checked again and again for vacuum leaks, pretty sure I've got them all, but SITLL ITS like only 5% of the time, but it feels like the engine just cuts out when I am accelerating, 95% its just into 2nd gear, a little after I have started slowly giving gas... but I can feel a “unrhythm” sometimes at random conditions, but like I said, only like 1 day out of the week; the car is my daily driver

!!.H.E.L.P.!!
 

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Your EGR kicks in for highway driving, and better emissions.. It opens slowly with vacuum, if your EGR is faulty the emissions will be bad but if you deleted the EGR I am not sure it would effect this bumble that you are experiencing...
I am unfamiliar with the workings of the speed density thing.. I'm going to read up on it and check it out.... I will also go scross the bumble with a smog guy I know that can tell me about the EGR on your car, and it's effects.

PM me on the EGR is yours Electrical or is it operated by a Vacuum line and Thermostatic switches?

FE
 

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Discussion Starter · #11 ·

If the egr valve does not open then you have a sureity of it either being stuck (replace it) or it's got a bad diaphragm (replace it).
FE

Sadly, I just went ahead and tested this today before recieving your PM, I apply vaccum to the hose connceted to the diaphragm and can see movement, it seems to easily move both directions, and it holds vaccum for >1 min.
When the car is running and I apply the vaccum, it stumbles... starts dying ... doesn't recover unitl I equlize the pressure in the line (remove the vaccum..)

::SUK!!::

<font size=-1>[ This Message was edited by: 67fastback on 5/10/06 9:48am ]</font>
 
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