940 turbo, 1993, sluggish and fuel rich (gray smoke)

MSMMMDD · Post by **MSMMMDD** » 30 Sep 2009, 06:14

Very new to the forum and Volvo's. This first Volvo ever owned.

I have a code 1-1-3 (Short term fuel trim (Lambda control) too lean / rich). What does this mean?

The car is running rich under load and warmed up. The issue appears to be worse at operating temperature.

I beleive the O2 sensor may be bad. That is how I found the forum. Does anyone have any additional ideas before I start replacing parts?

Thank you for the help.

Post by **billofdurham** » 30 Sep 2009, 12:53

Welcome to Matthew's Volvo Site.

The engine control module (ECM) receives information from the oxygen sensor which indicates if the fuel/air ratio is too rich or too lean. If it is outside the parameters the ECM will compensate.

Try erasing the codes and see what happens. Sometimes that will clear the problem.

Bill.

MSMMMDD · Post by **MSMMMDD** » 30 Sep 2009, 14:20

Great minds think alike.

I did that last night and then cranked it up. No check engine light until the motor got to temperature. Then I got the light.

Same result no power in second gear under load, can't get to third very fuel rich.

I went ahead and got an O2 sensor, got lucky...not the $250 one. It looks original and the car has over 150K miles on it. Wish me luck.

MSMMMDD · Post by **MSMMMDD** » 30 Sep 2009, 19:33

The old O2 sensor was completely coated in soot. Went ahead and replaced it just to see. Didn't expect much.

No "Check Engine" light now, but still running too rich (no power in 2nd gear...smoke). Based on a post placed on feb 2nd 2006, I probably have a few options:
High fuel pressure, contaminated oil, a leaking injector, an exhaust leak, or a leaking canister purge valve.

I do not know where I should check the fuel pressure or what its proper range is. Also, I do not know how to check the injectors or a purge valve. Does anyone have any suggestions?

Also, does anyone know where I can purchase a Haynes manual for the 940?

DeRail · Post by **DeRail** » 01 Oct 2009, 17:47

If you can locate the purge valve (I'm not sure where it's located on the 940) make sure that any vacuum lines , etc. routed to it are not cracked or restricted.

MSMMMDD · Post by **MSMMMDD** » 01 Oct 2009, 22:09

Thanks for the info. You wouldn't happen to know how to check the fuel pressure, I can't find a port.

Post by **billofdurham** » 02 Oct 2009, 12:30

Attached has fuel pressure pipes , from VADIS, and how to check fuel pressure.

940 fuel pressure.pdf: (1.19 MiB) Downloaded 658 times

Bill.

MSMMMDD · Post by **MSMMMDD** » 03 Oct 2009, 06:50

Thank you,

Two more questions:

1) On the fuel tube to the injectors, there is a threaded port, can I use that to attach the fuel gage?

2) Someone at work suggested I check the probe point 6 of the readout, I got a code:
2-1-4 (RPM signal absent intermittently - Could this cause the issue?

3) I then rechecked probe point 2 and got 2 more codes 2-3-1 and 2-3-2 Both indicating lean/rich issues and based on the smoke under load , it is rich.

The more I look, ...the worse it gets.

Post by **billofdurham** » 03 Oct 2009, 11:57

The valve is part #1a on the parts list.

Port 6 on the OBD is for the ignition system. Attached is for code 2-1-4:

940 DTC 2-1-4.pdf: (55.93 KiB) Downloaded 253 times

Port 2 is for the fuel injection and both codes 2-3-1 and 2-3-2 are basically the same problem. The possible causes are what you are already investigating - high fuel pressure; contaminated engine oil; leaking injector; leaking canister purge valve; leaking exhaust system

Don't read too much into the codes as some are set by others and do not necessarily mean that more is going wrong.

Bill.

MSMMMDD · Post by **MSMMMDD** » 03 Oct 2009, 13:19

Thanks, I am going to get it right now.

I took it to Firestone and it made them scratch their head. Could not hook it up to diagnose it. Told me it was acting like a Catalitic Converter. Does that make any sense?