Hello collect board members,

This is about a 1990 740 turbo and the engine code 113.
Some background info and recent repairs include a exhaust manifold gasket replacement. Long story short, one of the three bolts from the turbo to exhaust down pipe was broken off. It was drilled out and in the process a little bit of oil was left on the manifold. Upon completing re-installation the engine was turned on and quite a bit of smoke burned off the remaining oil residue.

I guess I should have cleaned everything better but it's all done now. After running fine about 5 min the car was turned off. Then restarted but the check engine light came on and pulled the code 113. So are we looking for a vac leak in some of the tubing or do you think the smoke killed the o2 sensor? Of course I have not done any diagnostics yet because it snowed here 5" last night. I will test run the car today and look for more symptoms.

Thanks to all, Greg

 

113 is a generic fuel injector code. The small amount of oil did not kill the O2 unless it already was right on the edge. If you ran for any length of time w/ that manifold leaking, the O2 would have read the mixture as lean and the ecu would have increased fueling meaning the engine would run rich. A rich mixture will kill the O2 and the converter.

 

Alright so, what might I be looking for?
Today I cleared the code using the battery.
After 15 min of driving it came back, same code.
I'd like to rule this out one thing at a time.
Any ideas?

 

It may be something as simple as poor ground wire attachment on the main two fuel rail mounting bolts. Those wires are the grounds for the injectors. They can get corroded or damaged...a good place to start. Since work was done on the passenger side of the motor opposite of the intake and injectors, I'd look in that area next. The gray multi-connectors going through the passenger side fire wall behind the accumulator and that area in general.

 

I'm looking all over but it seems like everything is connected fine?
Will keep checking. There has got to be another possibility than just a wire.
On another note Swift check your PM.

 

For your LH2.4 car code 1-1-3 means too rich or too lean ...
Engine and OBD Diagnostic Codes

During idle with everything connected, measure the output voltage of the o2 sensor (thick green wire). If working properly the voltage should be constantly swinging between ~.2 and ~.8 VDC.

 

Alright well when it come to the mechanical we can try and take it apart. Electrical things are another matter. I have a volt meter and this is going to sound dumb but I have no real knowledge of how to use it. Will one of the connects have to touch the inside of the wire or does the outside display current? Also will the other connection on the volt meter have to be grounded? I understand how to check for broken wires but that's about all.

 

Set the meter to VDC. Peel back the rubber boot where the sensor's output connects to the thick green wire on the firewall, attach the red lead from the meter to the metal connector. The black lead from the meter can be grounded to anything metal (fuel rail, etc)

 

So it does not need to be connected in circuit, good to know.
Thanks, I'll try that and report back.