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Topic: Finally codes on 87 3.8 please help (Read 1471 times) previous topic - next topic

Finally codes on 87 3.8 please help

It took running a power wire to the cigar lighter to power up the Actron diagnostic tool (for whatever reason) but we were able to retrieve codes.
The codes are 13, 41 and 91 all fuel related.
Any help is appreciated

Finally codes on 87 3.8 please help

Reply #1
41and 91 are left and right oxygen sensor lean codes. 13 is the idle too high. So I can guess at a couple possible causes.

Check the oxygen sensor ground. That can be the cause of those 3 codes.

Another possibility is a vacuum leak. Stick a vacuum gauge on the car at see what it's reading/what the needle does.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Finally codes on 87 3.8 please help

Reply #2
Oxygen sensor ground?
Where is this?

Finally codes on 87 3.8 please help

Reply #3
From the 87 EVTM:
The ground wires are part of the HEGO cable harness. Each side has a ground wire to the back of the head.
G213 & G214 in the pic. One of the ground wires is orange and the other is gray/red stripe.
The pic shows an extra wire RH side ground.

Here is a procedure for using a vacuum gauge. Check scenarios 10 & 12 for vacuum leaks:
 http://www.secondchancegarage.com/public/186.cfm

Finally codes on 87 3.8 please help

Reply #4
Thunderjet302 and softtouch you two are AWESOME and will probably be the guys that help me get the Gremlins out of the Walking bird I appreciate both of you for the help.
We reworked the ground from the battery this past weekend so we know grounds are important.
I get the use of a Snap On diagnostic tool for the weekend so some good should be coming soon.

Finally codes on 87 3.8 please help

Reply #5
Pulled the fuel tank as I ordered a new one along with a new fuel pump, the gasoline was tea colored and the fuel pressure was at 36 psi also replacing O2 sensors.
Fingers crossed I should get rid of the rough idle.

Finally codes on 87 3.8 please help

Reply #6
VICTORIOUS!!

I was way off with timing,
Timing keeps everything from happening all at once!!

Finally codes on 87 3.8 please help

Reply #7
I have a small vaspooge leak at the throttle position sensor, is this a worn out throttle shaft? or could something else cause this?