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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Running REALLY Rich...next steps?

  • Thread starter Thread starter 5.0L Miata
  • Start date Start date Sep 4, 2007

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Sep 4, 2007
#1
  • Sep 4, 2007
  • #1
Hey All,

I've checked all of my vacuum connections and everything seems ok...although I still am getting a poor vacuum reading? The car is running VERY rich, so rich in fact that the black smoke begins to choke me in the garage after about 30 seconds of idle.

I've tried running the codes as well using the instructions on here, and I get nothing on my test light or voltmeter? If I pull the paper clip in and out I do get a change in engine rpm, and I could hear the engine go through different rpm stages with the clip in, but nothing visible comes up?

Can someone describe to me what the EGR Vacuum regulator looks like? I think that it is the one on the firewall with an upper and lower connection, one grey and one black vacuum hose? If I connect this to the EGR valve as is required and then connect the FPR directly to the manifold vacuum (is this correct) then the car idles like crap and will stall with throttle application. If I connect the FPR to this solonoid on the firewall and then the EGR directly to manifold vacuum it will at least idle but pukes out black smoke.

Some help would be fantastic!

Thanks.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Sep 4, 2007
#2
  • Sep 4, 2007
  • #2
no codes eh? sounds like you are having the same issue I was having. ECT is gone. Your engine maybe running with the choke on basically. look at the thread Starting Blues and use the values in there to test the sensor.
 

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Sep 4, 2007
#3
  • Sep 4, 2007
  • #3
ECT...that is the one for the coolant temps correct? If so, I just purchased and installed a new one today. Still same results.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Sep 5, 2007
#4
  • Sep 5, 2007
  • #4
hrmmm well the other one is the Inlet Air temp sensor. Usally you would get a code if that is an issue.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 5, 2007
#5
  • Sep 5, 2007
  • #5
The car should stall at idle with the EGR receiving manifold vacuum.

I'd find Jrichker's post on testing the self test connector wiring. There are a couple of computer pins which you check continuity on IIRC. If you can get the ability to see codes, that's gonna help.

Have you checked the MAP sensor's vacuum source? Ensure it shows full manifold vac (about 20" hg at idle) and decreases as RPM-per-time increases.

Good luck.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,194
17,889
224
Massachusetts
Sep 5, 2007
#6
  • Sep 5, 2007
  • #6
5.0L Miata said:
I've tried running the codes as well using the instructions on here, and I get nothing on my test light or voltmeter? If I pull the paper clip in and out I do get a change in engine rpm, and I could hear the engine go through different rpm stages with the clip in, but nothing visible comes up?
Click to expand...



It sounds like the engine is going through it's code reading process, but it's not blinking the light or you don't have it plugged into the correct port on the test plug.

You could just buy a $30 reader?

Are you sure your test light works? Is it in the right port on the plug?


You don't want the EGR to get direct vacuum. it will open when it's not supposed to. The FPR however does see direct vacuum from the manifold
 
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